Intensive versus standard blood pressure control and overall brain small vessel disease burden: a post-hoc analysis of the SPRINT randomized clinical trial.
The 7 matches
- [1] § Methods › Trial design and participants ↔ SVD_SPRINT_Git_20260705.R, lines 1–51 · score 0.88 · glomerular filtration rate, subclinical cardiovascular disease, mmHg, bodies, medications, visit
- [2] § Results › Attained SBP reduction and SVD change ↔ SVD_SPRINT_Git_20260705.R, lines 1–51 · score 0.87 · systolic blood pressure, basal ganglia perivascular, Dummy variables, periventricular white matter, baseline age, free water
- [3] § Methods › Statistical analysis › Sensitivity analyses ↔ SVD_SPRINT_Git_20260705.R, lines 1228–1275 · score 0.70 · auxiliary variables, available baseline MRI, LCS models, ICV, race, likelihood
- [4] § Methods › Statistical analysis › Effect of treatment assignment on SVD burden ↔ SVD_SPRINT_Git_20260705.R, lines 683–721 · score 0.68 · square root, model implied, variance, regressions, Score, covariates
- [5] § Methods › Statistical analysis › SVD measurement model and invariance testing strategy ↔ SVD_SPRINT_Git_20260705.R, lines 267–307 · score 0.64 · examine conceptually plausible, DIF, MIMIC, invariance, fit, latent
- [6] § Results › SVD measurement model and longitudinal measurement invariance ↔ SVD_SPRINT_Git_20260705.R, lines 53–93 · score 0.55 · configural invariance model, measurement invariance, metric, scalar, longitudinal, covariance
- [7] § Results › Effect of treatment assignment on SVD burden ↔ SVD_SPRINT_Git_20260705.R, lines 1228–1275 · score 0.51 · available baseline MRI, change score, SVD burden, LCS model, Cohen, treatment
Paper
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The authors' code
R · 1,639 lines · 56 KB · no license · 7 matches
- # Load required libraries
- libraries <- c(
- 'tidyverse',
- 'lavaan',
- 'semTools',
- 'semPlot',
- 'semptools',
- 'parallel'
- )
- invisible(lapply(libraries, require, character.only = TRUE))
- rm(libraries)
- #//----- VARIABLE DICTIONARY -----
- # wide0: SPRINT dataset in wide format with participants who completed baseline MRI scan that passed quality control and had complete data on SVD indicators
- # wide01: SPRINT dataset in wide format with participants who completed both baseline and follow-up MRI scans that passed quality control and had complete data on SVD indicators
- # r_pvwml.0: rescaled periventricular white matter hyperintensity volume at baseline
- # r_pvwml.1: rescaled periventricular white matter hyperintensity volume at follow-up
- # r_fw.0: rescaled mean white matter free water at baseline
- # r_fw.1: rescaled mean white matter free water at follow-up
- # r_bgepvsc.0: rescaled basal ganglia perivascular space count at baseline
- # r_bgepvsc.1: rescaled basal ganglia perivascular space count at follow-up
- # r_pvwmln.0: rescaled ROI volume-normalized periventricular white matter hyperintensity volume at baseline
- # r_pvwmln.1: rescaled ROI volume-normalized periventricular white matter hyperintensity volume at follow-up
- # r_bgepvscn.0: rescaled ROI volume-normalized basal ganglia perivascular space count at baseline
- # r_bgepvscn.1: rescaled ROI volume-normalized basal ganglia perivascular space count at follow-up
- # age.c.0: mean-centered baseline age
- # time_years.1: time of follow-up (in years)
- # treat: intensive (vs standard) BP group assignment binary indicator
- # female: female sex binary indicator
- # r_icv.0: rescaled total intracranial volume at baseline
- # race: dummy variable vector for race/ethnicity with "White" as reference
- # edu: dummy variable vector for education with "College degree" as reference
- # smk: dummy variable vector for smoking with "Never" as reference
- # polyph: dummy variable vector for polypharmacy with "<5 medications" as reference
- # sub_cvd: subclinical cardiovascular disease binary indicator
- # sbp: systolic blood pressure at baseline visit
- # dbp: diastolic blood pressure at baseline visit
- # BMI: body mass index
- # HDL: fasting high-density lipoprotein cholesterol
- # result_CO2: serum bicarbonate
- # egfr: estimated glomerular filtration rate
- # log2_umalcr: log urine albumin-to-creatinine ratio
- # lm_delayed1: logical memory delayed score
- # sbp_group_1: dummy variable indicating attained SBP change from baseline of 0-10 mmHg
- # sbp_group_2: dummy variable indicating attained SBP change from baseline of 10-20 mmHg
- # sbp_group_3: dummy variable indicating attained SBP change from baseline of ≥20 mmHg
- # sbp_group_n: numeric attained SBP change group variable for linear trend calculation
- # sbp_delta: attained SBP change from baseline (continuous variable)
- #//--------------------------------------------------------------------------- START OF ANALYTIC CODE ---------------------------------------------------------------------------//
- #//-------------------------------------------- ANALYSES 3.2: SVD MEASUREMENT MODEL AND LONGITUDINAL MEASUREMENT INVARIANCE --------------------------------------------
- #//----- LONGITUDINAL INVARIANCE TESTING WITH RAW SVD INDICATORS -----
- # Testing for configural, metric (weak), and scalar (strong) measurement invariance using longitudinal CFA models for multiple indicator data
- # Configural invariance model (model 1)
- model1 <-paste0('
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw.0*r_fw.0 + bg.0*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw.1*r_fw.1 + bg.1*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ ipv.0*1
- r_fw.0 ~ ifw.0*1
- r_bgepvsc.0 ~ ibg.0*1
- r_pvwml.1 ~ ipv.1*1
- r_fw.1 ~ ifw.1*1
- r_bgepvsc.1 ~ ibg.1*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 0*1
- ')
- # Metric (weak) invariance model (model 2)
- model2 <-paste0('
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw*r_fw.0 + bg*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw*r_fw.1 + bg*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ ipv.0*1
- r_fw.0 ~ ifw.0*1
- r_bgepvsc.0 ~ ibg.0*1
- r_pvwml.1 ~ ipv.1*1
- r_fw.1 ~ ifw.1*1
- r_bgepvsc.1 ~ ibg.1*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 0*1
- ')
- # Scalar (strong) invariance model (model 3)
- model3 <-('
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw*r_fw.0 + bg*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw*r_fw.1 + bg*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ ipv*1
- r_fw.0 ~ ifw*1
- r_bgepvsc.0 ~ ibg*1
- r_pvwml.1 ~ ipv*1
- r_fw.1 ~ ifw*1
- r_bgepvsc.1 ~ ibg*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 1
- ')
- # Fit longitudinal CFA models with Maximum Likelihood estimation method using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fit1 <- lavaan::sem(model1, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- fit2 <- lavaan::sem(model2, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- fit3 <- lavaan::sem(model3, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- # Compare model fit indices
- fitm1 <- fitmeasures(fit1, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- fitm2 <- fitmeasures(fit2, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- fitm3 <- fitmeasures(fit3, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- fitm_all <- as.data.frame(rbind(fitm1, fitm2, fitm3))
- fitm_all <- fitm_all %>% mutate(across(where(is.numeric), function(x) {round(x, 3)}))
- print(fitm_all) # Supplemental Table 4; Models 1, 2, and 3
- # Display model summaries
- summary(fit1, fit.measures = TRUE, standardized = TRUE)
- summary(fit2, fit.measures = TRUE, standardized = TRUE)
- summary(fit3, fit.measures = TRUE, standardized = TRUE)
- #//----- LONGITUDINAL INVARIANCE TESTING WITH ROI VOLUME-NORMALIZED INDICATORS -----
- # Testing for configural, metric (weak), and scalar (strong) measurement invariance using longitudinal CFA models for multiple indicator data
- # Configural invariance model (model 4)
- model4 <-paste0('
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwmln.0 + fw.0*r_fw.0 + bg.0*r_bgepvscn.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwmln.1 + fw.1*r_fw.1 + bg.1*r_bgepvscn.1
- # Mean structure specification
- r_pvwmln.0 ~ ipv.0*1
- r_fw.0 ~ ifw.0*1
- r_bgepvscn.0 ~ ibg.0*1
- r_pvwmln.1 ~ ipv.1*1
- r_fw.1 ~ ifw.1*1
- r_bgepvscn.1 ~ ibg.1*1
- # Residual covariances
- r_pvwmln.0 ~~ r_pvwmln.1
- r_fw.0 ~~ r_fw.1
- r_bgepvscn.0 ~~ r_bgepvscn.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 0*1
- ')
- # Metric (weak) invariance model (model 5)
- model5 <-paste0('
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwmln.0 + fw*r_fw.0 + bg*r_bgepvscn.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwmln.1 + fw*r_fw.1 + bg*r_bgepvscn.1
- # Mean structure specification
- r_pvwmln.0 ~ ipv.0*1
- r_fw.0 ~ ifw.0*1
- r_bgepvscn.0 ~ ibg.0*1
- r_pvwmln.1 ~ ipv.1*1
- r_fw.1 ~ ifw.1*1
- r_bgepvscn.1 ~ ibg.1*1
- # Residual covariances
- r_pvwmln.0 ~~ r_pvwmln.1
- r_fw.0 ~~ r_fw.1
- r_bgepvscn.0 ~~ r_bgepvscn.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 0*1
- ')
- # Scalar (strong) invariance model (model 6)
- model6 <-('
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwmln.0 + fw*r_fw.0 + bg*r_bgepvscn.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwmln.1 + fw*r_fw.1 + bg*r_bgepvscn.1
- # Mean structure specification
- r_pvwmln.0 ~ ipv*1
- r_fw.0 ~ ifw*1
- r_bgepvscn.0 ~ ibg*1
- r_pvwmln.1 ~ ipv*1
- r_fw.1 ~ ifw*1
- r_bgepvscn.1 ~ ibg*1
- # Residual covariances
- r_pvwmln.0 ~~ r_pvwmln.1
- r_fw.0 ~~ r_fw.1
- r_bgepvscn.0 ~~ r_bgepvscn.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 1
- ')
- # Fit longitudinal CFA models with Maximum Likelihood estimation method using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fit4 <- lavaan::sem(model4, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- fit5 <- lavaan::sem(model5, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- fit6 <- lavaan::sem(model6, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- # Compare model fit indices
- fitm4 <- fitmeasures(fit4, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- fitm5 <- fitmeasures(fit5, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- fitm6 <- fitmeasures(fit6, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- fitm_all <- as.data.frame(rbind(fitm4, fitm5, fitm6))
- fitm_all <- fitm_all %>% mutate(across(where(is.numeric), function(x) {round(x, 3)}))
- print(fitm_all) # Supplemental Table 4; Models 4, 5, and 6
- # Display model summaries
- summary(fit4, fit.measures = TRUE, standardized = TRUE)
- summary(fit5, fit.measures = TRUE, standardized = TRUE)
- summary(fit6, fit.measures = TRUE, standardized = TRUE)
- #//----- MULTIPLE INDICATORS MULTIPLE CAUSES (MIMIC) MODELS TO EXAMINE CONCEPTUALLY PLAUSIBLE SOURCES OF DIFFERENTIAL ITEM FUNCTIONING (DIF) OVER TIME -----
- # MIMIC Model for periventricular white matter hyperintensity volume (pvwml)
- # Metric (weak) invariance model with both direct and indirect (through SVD) effects of age on pvwml (modeldif_wml)
- modeldif_wml <-paste0('
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw*r_fw.0 + bg*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw*r_fw.1 + bg*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ ipv.0*1
- r_fw.0 ~ ifw.0*1
- r_bgepvsc.0 ~ ibg.0*1
- r_pvwml.1 ~ ipv.1*1
- r_fw.1 ~ ifw.1*1
- r_bgepvsc.1 ~ ibg.1*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 0*1
- # Regressions on age
- svd_0 ~ age.c.0
- svd_1 ~ age.c.0 + time_years.1
- r_pvwml.0 ~ age.c.0
- r_pvwml.1 ~ age.c.0 + time_years.1
- ')
- # Fit longitudinal MIMIC model with Maximum Likelihood estimation method using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fitdif_wml <- lavaan::sem(modeldif_wml, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- summary(fitdif_wml, fit.measures = TRUE, standardized = TRUE)
- # Path diagram for pvwml MIMIC model (Supplementary Figure 1; panel A)
- pl_mod <- semPlotModel(fitdif_wml)
- pl_par <- pl_mod@Pars
- pl_par <- pl_par[!rownames(pl_par) %in% rownames(pl_par[pl_par$edge == "int", ]), ]
- pl_mod@Pars <- pl_par
- plt <- semPaths(pl_mod, whatLabels = "est", residuals = FALSE, intStyle = "multi", sizeInt = 9, edge.label.cex = 1.2)
- plt$layout[1, ] <- c(-1, 0.6) #p.0
- plt$layout[2, ] <- c(-0.7, 0.6) #f.0
- plt$layout[3, ] <- c(-0.4, 0.6) #b.0
- plt$layout[4, ] <- c(0.2, 0.6) #p.1
- plt$layout[6, ] <- c(0.5, 0.6) #f.1
- plt$layout[7, ] <- c(0.8, 0.6) #b.1
- plt$layout[5, ] <- c(-1.3, -0.2) #age.c.0
- plt$layout[8, ] <- c(-0.1, -0.2) #dufu
- plt$layout[9, ] <- c(-0.7, -0.8) #s_0
- plt$layout[10, ] <- c(0.5, -0.8) #s_1
- plt$graphAttributes$Nodes$labels <- c("Perive-\nticular\nWMH\nt0", "WM\nFree\nWater\nt0", "Basal\nganglia\nPVS\nt0",
- "Perive-\nticular\nWMH\nt1", "Base-\nline\nage", "WM\nFree\nWater\nt1",
- "Basal\nganglia\nPVS\nt1", "Follow\nup\ntime",
- "SVD\nt0", "SVD\nt1")
- plt <- semptools::mark_sig(semPaths_plot = plt, object = fitdif_wml)
- plt$graphAttributes$Nodes$label.cex <- 2
- plt$graphAttributes$Edges$curve[c(7)] <- 2
- plt$graphAttributes$Edges$curve[16] <- -1
- plt$graphAttributes$Edges$label.margin[c(7:9)] <- -0.035
- plt$graphAttributes$Edges$edge.label.position[14] <- 0.8
- plt$graphAttributes$Edges$edge.label.position[17] <- 0.7
- plt$plotOptions$label.prop <- c(0.8, 0.8, 0.8, 0.8, 0.7, 0.8, 0.8, 0.7, 0.6, 0.6)
- plt$graphAttributes$Edges$color[c(1:6)] <- "coral"
- plt$graphAttributes$Edges$color[c(7:9)] <- "lightgreen"
- plt$graphAttributes$Edges$color[c(10:12)] <- "magenta2"
- plt$graphAttributes$Edges$color[c(13:15)] <- "skyblue"
- plot(plt)
- # MIMIC Model for mean white matter free water (fw)
- # Metric (weak) invariance model with both direct and indirect (through SVD) effects of age on fw (modeldif_fw)
- modeldif_fw <-paste0('
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw*r_fw.0 + bg*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw*r_fw.1 + bg*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ ipv.0*1
- r_fw.0 ~ ifw.0*1
- r_bgepvsc.0 ~ ibg.0*1
- r_pvwml.1 ~ ipv.1*1
- r_fw.1 ~ ifw.1*1
- r_bgepvsc.1 ~ ibg.1*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 0*1
- # Regressions on age
- svd_0 ~ age.c.0
- svd_1 ~ age.c.0 + time_years.1
- r_fw.0 ~ age.c.0
- r_fw.1 ~ age.c.0 + time_years.1
- ')
- # Fit longitudinal MIMIC model with Maximum Likelihood estimation method using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fitdif_fw <- lavaan::sem(modeldif_fw, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- summary(fitdif_fw, fit.measures = TRUE, standardized = TRUE)
- # Path diagram for fw MIMIC model (Supplementary Figure 1; panel B)
- pl_mod <- semPlotModel(fitdif_fw)
- pl_par <- pl_mod@Pars
- pl_par <- pl_par[!rownames(pl_par) %in% rownames(pl_par[pl_par$edge == "int", ]), ]
- pl_mod@Pars <- pl_par
- plt <- semPaths(pl_mod, whatLabels = "est", residuals = FALSE, intStyle = "multi", sizeInt = 9, edge.label.cex = 1.2)
- plt$layout[1, ] <- c(-1, 0.6) #p.0
- plt$layout[2, ] <- c(-0.7, 0.6) #f.0
- plt$layout[3, ] <- c(-0.4, 0.6) #b.0
- plt$layout[4, ] <- c(-1.3, -0.2) #age.c.0
- plt$layout[5, ] <- c(0.5, 0.6) #f.1
- plt$layout[6, ] <- c(0.2, 0.6) #p.1
- plt$layout[7, ] <- c(0.8, 0.6) #b.1
- plt$layout[8, ] <- c(-0.1, -0.2) #dufu
- plt$layout[9, ] <- c(-0.7, -0.8) #s_0
- plt$layout[10, ] <- c(0.5, -0.8) #s_1
- plt$graphAttributes$Nodes$labels <- c("Perive-\nticular\nWMH\nt0", "WM\nFree\nWater\nt0", "Basal\nganglia\nPVS\nt0",
- "Base-\nline\nage",
- "WM\nFree\nWater\nt1", "Perive-\nticular\nWMH\nt1", "Basal\nganglia\nPVS\nt1",
- "Follow\nup\ntime",
- "SVD\nt0", "SVD\nt1")
- plt <- semptools::mark_sig(semPaths_plot = plt, object = fitdif_fw)
- plt$graphAttributes$Nodes$label.cex <- 2
- plt$graphAttributes$Edges$curve[c(8)] <- 2
- plt$graphAttributes$Edges$curve[16] <- -1
- plt$graphAttributes$Edges$label.margin[c(7:9)] <- -0.035
- plt$graphAttributes$Edges$edge.label.position[14] <- 0.72
- plt$graphAttributes$Edges$edge.label.position[17] <- 0.7
- plt$plotOptions$label.prop <- c(0.8, 0.8, 0.8, 0.7, 0.8, 0.8, 0.8, 0.7, 0.6, 0.6)
- plt$graphAttributes$Edges$color[c(1:6)] <- "coral"
- plt$graphAttributes$Edges$color[c(7:9)] <- "lightgreen"
- plt$graphAttributes$Edges$color[c(10:12)] <- "magenta2"
- plt$graphAttributes$Edges$color[c(13:15)] <- "skyblue"
- plot(plt)
- # MIMIC Model for basal ganglia perivascular space count (bgepvsc)
- # Metric (weak) invariance model with both direct and indirect (through SVD) effects of age on bgepvsc (modeldif_pvs)
- modeldif_pvs <-paste0('
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw*r_fw.0 + bg*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw*r_fw.1 + bg*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ ipv.0*1
- r_fw.0 ~ ifw.0*1
- r_bgepvsc.0 ~ ibg.0*1
- r_pvwml.1 ~ ipv.1*1
- r_fw.1 ~ ifw.1*1
- r_bgepvsc.1 ~ ibg.1*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 0*1
- # Regressions on age
- svd_0 ~ age.c.0
- svd_1 ~ age.c.0 + time_years.1
- r_bgepvsc.0 ~ age.c.0
- r_bgepvsc.1 ~ age.c.0 + time_years.1
- ')
- # Fit longitudinal MIMIC model with Maximum Likelihood estimation method using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fitdif_pvs <- lavaan::sem(modeldif_pvs, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- summary(fitdif_pvs, fit.measures = TRUE, standardized = TRUE)
- # Path diagram for bgepvsc MIMIC model (Supplementary Figure 1; panel C)
- pl_mod <- semPlotModel(fitdif_pvs)
- pl_par <- pl_mod@Pars
- pl_par <- pl_par[!rownames(pl_par) %in% rownames(pl_par[pl_par$edge == "int", ]), ]
- pl_mod@Pars <- pl_par
- plt <- semPaths(pl_mod, whatLabels = "est", residuals = FALSE, intStyle = "multi", sizeInt = 9, edge.label.cex = 1.2)
- plt$layout[1, ] <- c(-1, 0.6) #p.0
- plt$layout[2, ] <- c(-0.7, 0.6) #f.0
- plt$layout[3, ] <- c(-0.4, 0.6) #b.0
- plt$layout[4, ] <- c(-1.3, -0.2) #age.c.0
- plt$layout[5, ] <- c(0.2, 0.6) #p.1
- plt$layout[6, ] <- c(0.8, 0.6) #b.1
- plt$layout[7, ] <- c(0.5, 0.6) #f.1
- plt$layout[8, ] <- c(-0.1, -0.2) #dufu
- plt$layout[9, ] <- c(-0.7, -0.8) #s_0
- plt$layout[10, ] <- c(0.5, -0.8) #s_1
- plt$graphAttributes$Nodes$labels <- c("Perive-\nticular\nWMH\nt0", "WM\nFree\nWater\nt0", "Basal\nganglia\nPVS\nt0",
- "Base-\nline\nage",
- "Perive-\nticular\nWMH\nt1", "Basal\nganglia\nPVS\nt1", "WM\nFree\nWater\nt1",
- "Follow\nup\ntime",
- "SVD\nt0", "SVD\nt1")
- plt <- semptools::mark_sig(semPaths_plot = plt, object = fitdif_pvs)
- plt$graphAttributes$Nodes$label.cex <- 2
- plt$graphAttributes$Edges$curve[c(9)] <- 2
- plt$graphAttributes$Edges$curve[16] <- -1
- plt$graphAttributes$Edges$label.margin[c(7:9)] <- -0.035
- plt$graphAttributes$Edges$edge.label.position[14] <- 0.6
- plt$graphAttributes$Edges$edge.label.position[17] <- 0.7
- plt$plotOptions$label.prop <- c(0.8, 0.8, 0.8, 0.7, 0.8, 0.8, 0.8, 0.7, 0.6, 0.6)
- plt$graphAttributes$Edges$color[c(1:6)] <- "coral"
- plt$graphAttributes$Edges$color[c(7:9)] <- "lightgreen"
- plt$graphAttributes$Edges$color[c(10:12)] <- "magenta2"
- plt$graphAttributes$Edges$color[c(13:15)] <- "skyblue"
- plot(plt)
- #//----- LONGITUDINAL INVARIANCE TESTING ACCOUNTING FOR TIME-VARYING AGE EFFECTS WITH RAW SVD INDICATORS -----
- # Testing for configural, metric (weak), and scalar (strong) measurement invariance using longitudinal CFA models for multiple indicator data
- # Configural invariance model (model 7)
- model7 <-paste0('
- r_pvwml.0 ~ age.c.0
- r_pvwml.1 ~ age.c.0 + time_years.1
- r_fw.0 ~ age.c.0
- r_fw.1 ~ age.c.0 + time_years.1
- r_bgepvsc.0 ~ age.c.0
- r_bgepvsc.1 ~ age.c.0 + time_years.1
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw.0*r_fw.0 + bg.0*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw.1*r_fw.1 + bg.1*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ ipv.0*1
- r_fw.0 ~ ifw.0*1
- r_bgepvsc.0 ~ ibg.0*1
- r_pvwml.1 ~ ipv.1*1
- r_fw.1 ~ ifw.1*1
- r_bgepvsc.1 ~ ibg.1*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 0*1
- ')
- # Metric (weak) invariance model (model 8)
- model8 <-paste0('
- r_pvwml.0 ~ age.c.0
- r_pvwml.1 ~ age.c.0 + time_years.1
- r_fw.0 ~ age.c.0
- r_fw.1 ~ age.c.0 + time_years.1
- r_bgepvsc.0 ~ age.c.0
- r_bgepvsc.1 ~ age.c.0 + time_years.1
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw*r_fw.0 + bg*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw*r_fw.1 + bg*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ ipv.0*1
- r_fw.0 ~ ifw.0*1
- r_bgepvsc.0 ~ ibg.0*1
- r_pvwml.1 ~ ipv.1*1
- r_fw.1 ~ ifw.1*1
- r_bgepvsc.1 ~ ibg.1*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 0*1
- ')
- # Scalar (strong) invariance model (model 9)
- model9 <-('
- r_pvwml.0 ~ age.c.0
- r_pvwml.1 ~ age.c.0 + time_years.1
- r_fw.0 ~ age.c.0
- r_fw.1 ~ age.c.0 + time_years.1
- r_bgepvsc.0 ~ age.c.0
- r_bgepvsc.1 ~ age.c.0 + time_years.1
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw*r_fw.0 + bg*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw*r_fw.1 + bg*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ ipv*1
- r_fw.0 ~ ifw*1
- r_bgepvsc.0 ~ ibg*1
- r_pvwml.1 ~ ipv*1
- r_fw.1 ~ ifw*1
- r_bgepvsc.1 ~ ibg*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 1
- ')
- # Fit longitudinal CFA models with Maximum Likelihood estimation method using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fit7 <- lavaan::sem(model7, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- fit8 <- lavaan::sem(model8, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- fit9 <- lavaan::sem(model9, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- # Compare model fit indices
- fitm7 <- fitmeasures(fit7, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- fitm8 <- fitmeasures(fit8, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- fitm9 <- fitmeasures(fit9, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- fitm_all <- as.data.frame(rbind(fitm7, fitm8, fitm9))
- fitm_all <- fitm_all %>% mutate(across(where(is.numeric), function(x) {round(x, 3)}))
- print(fitm_all) # Supplemental Table 4; Models 7, 8, and 9
- # Display model summaries
- summary(fit7, fit.measures = TRUE, standardized = TRUE)
- summary(fit8, fit.measures = TRUE, standardized = TRUE)
- summary(fit9, fit.measures = TRUE, standardized = TRUE)
- #//----- PARAMETER ESTIMATES FOR THE COVARIANCE AND MEAN STRUCTURE OF THE SVD MEASUREMENT MODEL -----
- # Supplemental Tables 5 and 6
- # Model summary
- sum <- summary(fit9, fit.measures = TRUE, standardized = TRUE, rsquare = TRUE)
- # Model diagnostics
- lavInspect(fit9, "sampstat") # sample covariance matrix
- lavInspect(fit9, "implied") # model-implied covariance matrix
- lavInspect(fit9, "resid") # difference between observed and model-implied covariance matrix (unstandardized and unscaled model residuals)
- lavResiduals(fit9, type = "cor.bentler")$cov # unstandardized model residuals after transformation to correlation matrix and rescaling (by dividing the elements by the square roots of the corresponding variances of the observed covariance matrix)
- lavResiduals(fit9, type = "cor.bentler")$cov.z # standardized model residuals after transformation to correlation matrix and rescaling (by dividing the elements by the square roots of the corresponding variances of the observed covariance matrix)
- modindices(fit9, sort. = TRUE, standardized = TRUE) # sorted (from largest to smallest) model modification indices
- lavTestScore(fit9, cumulative = TRUE) # Score test (or Lagrange Multiplier test) for releasing one or more fixed or constrained parameters in model
- # Display baseline and follow-up loadings
- load <- sum$pe[sum$pe$op == "=~", c("rhs", "est", "se", "std.all")]
- load <- load %>% mutate(across(where(is.numeric), function(x) {formatC(x, format = "f", digits = 3)}))
- print(load)
- # Display baseline and follow-up age regression coefficients
- reg <- sum$pe[sum$pe$op == "~", c("lhs", "rhs", "est", "se", "std.all")]
- reg <- reg %>% mutate(across(where(is.numeric), function(x) {formatC(x, format = "f", digits = 3)}))
- print(reg)
- # Display baseline and follow-up residual (error) variances
- er <- sum$pe[((sum$pe$op == "~~") & (sum$pe$lhs == sum$pe$rhs)), c("lhs", "rhs", "est", "se", "std.all")]
- er <- er %>% mutate(across(where(is.numeric), function(x) {formatC(x, format = "f", digits = 3)}))
- print(er)
- # Display factor covariance
- cov <- sum$pe[((sum$pe$op == "~~") & (sum$pe$lhs != sum$pe$rhs)), c("lhs", "op", "rhs", "est", "se", "std.all")]
- cov <- cov %>% mutate(across(where(is.numeric), function(x) {formatC(x, format = "f", digits = 3)}))
- print(cov)
- # Display intercepts
- int <- sum$pe[(sum$pe$op == "~1"), c("lhs", "op", "rhs", "est", "se", "std.all")]
- int <- int %>% mutate(across(where(is.numeric), function(x) {formatC(x, format = "f", digits = 3)}))
- print(int)
- #//----- LONGITUDINAL INVARIANCE TESTING ACCOUNTING FOR TIME-VARYING AGE EFFECTS WITH ROI VOLUME-NORMALIZED SVD INDICATORS -----
- # Testing for configural, metric (weak), and scalar (strong) measurement invariance using longitudinal CFA models for multiple indicator data
- # Configural invariance model (model 10)
- model10 <-paste0('
- r_pvwmln.0 ~ age.c.0
- r_pvwmln.1 ~ age.c.0 + time_years.1
- r_fw.0 ~ age.c.0
- r_fw.1 ~ age.c.0 + time_years.1
- r_bgepvscn.0 ~ age.c.0
- r_bgepvscn.1 ~ age.c.0 + time_years.1
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwmln.0 + fw.0*r_fw.0 + bg.0*r_bgepvscn.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwmln.1 + fw.1*r_fw.1 + bg.1*r_bgepvscn.1
- # Mean structure specification
- r_pvwmln.0 ~ ipv.0*1
- r_fw.0 ~ ifw.0*1
- r_bgepvscn.0 ~ ibg.0*1
- r_pvwmln.1 ~ ipv.1*1
- r_fw.1 ~ ifw.1*1
- r_bgepvscn.1 ~ ibg.1*1
- # Residual covariances
- r_pvwmln.0 ~~ r_pvwmln.1
- r_fw.0 ~~ r_fw.1
- r_bgepvscn.0 ~~ r_bgepvscn.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 0*1
- ')
- # Metric (weak) invariance model (model 11)
- model11 <-paste0('
- r_pvwmln.0 ~ age.c.0
- r_pvwmln.1 ~ age.c.0 + time_years.1
- r_fw.0 ~ age.c.0
- r_fw.1 ~ age.c.0 + time_years.1
- r_bgepvscn.0 ~ age.c.0
- r_bgepvscn.1 ~ age.c.0 + time_years.1
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwmln.0 + fw*r_fw.0 + bg*r_bgepvscn.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwmln.1 + fw*r_fw.1 + bg*r_bgepvscn.1
- # Mean structure specification
- r_pvwmln.0 ~ ipv.0*1
- r_fw.0 ~ ifw.0*1
- r_bgepvscn.0 ~ ibg.0*1
- r_pvwmln.1 ~ ipv.1*1
- r_fw.1 ~ ifw.1*1
- r_bgepvscn.1 ~ ibg.1*1
- # Residual covariances
- r_pvwmln.0 ~~ r_pvwmln.1
- r_fw.0 ~~ r_fw.1
- r_bgepvscn.0 ~~ r_bgepvscn.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 0*1
- ')
- # Scalar (strong) invariance model (model 12)
- model12 <-('
- r_pvwmln.0 ~ age.c.0
- r_pvwmln.1 ~ age.c.0 + time_years.1
- r_fw.0 ~ age.c.0
- r_fw.1 ~ age.c.0 + time_years.1
- r_bgepvscn.0 ~ age.c.0
- r_bgepvscn.1 ~ age.c.0 + time_years.1
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwmln.0 + fw*r_fw.0 + bg*r_bgepvscn.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwmln.1 + fw*r_fw.1 + bg*r_bgepvscn.1
- # Mean structure specification
- r_pvwmln.0 ~ ipv*1
- r_fw.0 ~ ifw*1
- r_bgepvscn.0 ~ ibg*1
- r_pvwmln.1 ~ ipv*1
- r_fw.1 ~ ifw*1
- r_bgepvscn.1 ~ ibg*1
- # Residual covariances
- r_pvwmln.0 ~~ r_pvwmln.1
- r_fw.0 ~~ r_fw.1
- r_bgepvscn.0 ~~ r_bgepvscn.1
- # Latent variable means
- svd_0 ~ 0*1
- svd_1 ~ 1
- ')
- # Fit longitudinal CFA models with Maximum Likelihood estimation method using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fit10 <- lavaan::sem(model10, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- fit11 <- lavaan::sem(model11, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- fit12 <- lavaan::sem(model12, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- # Compare model fit indices
- fitm10 <- fitmeasures(fit10, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- fitm11 <- fitmeasures(fit11, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- fitm12 <- fitmeasures(fit12, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- fitm_all <- as.data.frame(rbind(fitm10, fitm11, fitm12))
- fitm_all <- fitm_all %>% mutate(across(where(is.numeric), function(x) {round(x, 3)}))
- print(fitm_all) # Supplemental Table 4; Models 10, 11, and 12
- # Display model summaries
- summary(fit10, fit.measures = TRUE, standardized = TRUE)
- summary(fit11, fit.measures = TRUE, standardized = TRUE)
- summary(fit12, fit.measures = TRUE, standardized = TRUE)
- #//----- MULTIPLE-INDICATOR LATENT CHANGE SCORE (LCS) MODELS -----
- # LCS model equivalent to longitudinal CFA model 9
- model13 <-paste0('
- r_pvwml.0 ~ age.c.0
- r_pvwml.1 ~ age.c.0 + time_years.1
- r_fw.0 ~ age.c.0
- r_fw.1 ~ age.c.0 + time_years.1
- r_bgepvsc.0 ~ age.c.0
- r_bgepvsc.1 ~ age.c.0 + time_years.1
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw*r_fw.0 + bg*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw*r_fw.1 + bg*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ 0*1
- r_fw.0 ~ ifw*1
- r_bgepvsc.0 ~ ibg*1
- r_pvwml.1 ~ 0*1
- r_fw.1 ~ ifw*1
- r_bgepvsc.1 ~ ibg*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent change
- svd_1 ~ 1*svd_0
- dC =~ 1*svd_1
- # Latent variable mean structure
- svd_0 ~ 1
- svd_1 ~ 0*1
- dC ~ 1
- # Latent variable covariance structure
- svd_0 ~~ svd_0
- svd_1 ~~ 0*svd_1
- dC ~~ dC
- dC ~~ svd_0
- ')
- # Fit LCS model with Maximum Likelihood estimation method using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fit13 <- lavaan::sem(model13, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- summary(fit13, fit.measures = TRUE, standardized = TRUE)
- # Compare models (sanity check)
- lavTestLRT(fit9, fit13)
- # Compare model fit indices (sanity check)
- fitm9 <- fitmeasures(fit9, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "tli.robust",
- "rmsea.robust", "srmr"))
- fitm13 <- fitmeasures(fit13, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "tli.robust",
- "rmsea.robust", "srmr"))
- fitm_all <- as.data.frame(rbind(fitm9, fitm13))
- fitm_all <- fitm_all %>% mutate(across(where(is.numeric), function(x) {round(x, 3)}))
- print(fitm_all)
- #//-------------------------------------------- ANALYSES 3.3: EFFECT OF TREATMENT ASSIGNMENT ON SVD BURDEN --------------------------------------------
- #//----- COMPUTE UNADJUSTED TREATMENT EFFECT -----
- # LCS model with treatment arm as latent change score predictor (unadjusted)
- model1 <-paste0('
- r_pvwml.0 ~ age.c.0
- r_pvwml.1 ~ age.c.0 + time_years.1
- r_fw.0 ~ age.c.0
- r_fw.1 ~ age.c.0 + time_years.1
- r_bgepvsc.0 ~ age.c.0
- r_bgepvsc.1 ~ age.c.0 + time_years.1
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw*r_fw.0 + bg*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw*r_fw.1 + bg*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ 0*1
- r_fw.0 ~ ifw*1
- r_bgepvsc.0 ~ ibg*1
- r_pvwml.1 ~ 0*1
- r_fw.1 ~ ifw*1
- r_bgepvsc.1 ~ ibg*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent change
- svd_1 ~ 1*svd_0
- dC =~ 1*svd_1
- # Latent variable mean structure
- svd_0 ~ a0*1
- svd_1 ~ 0*1
- dC ~ 1 + a*treat
- # Latent variable covariance structure
- svd_0 ~~ svd_0
- svd_1 ~~ 0*svd_1
- dC ~~ b*dC
- dC ~~ svd_0
- # Standardized mean difference (Cohens d) and % change relative to mean baseline SVD burden
- cohen_d := a/sqrt(b)
- prop := a/a0
- ')
- # Fit LCS model with Maximum Likelihood estimation method using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fit1 <- lavaan::sem(model1, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- summary(fit1, fit.measures = TRUE, standardized = TRUE)
- # Inspect fit indices
- fitmeasures(fit1, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- # Display parameter estimates of interest
- parameterEstimates(fit1)[parameterEstimates(fit1)$label %in%
- c("a", "cohen_d", "prop"),
- c("lhs", "est", "ci.lower", "ci.upper")]
- # Display latent change score variance
- parameterEstimates(fit1)[parameterEstimates(fit1)$label %in% "b", "est"]
- # Path diagram for the unadjusted treatment effect (Figure 2; panel A)
- pl_mod <- semPlotModel(fit1)
- pl_par <- pl_mod@Pars
- pl_par <- pl_par[!rownames(pl_par) %in% rownames(pl_par[pl_par$edge == "int" & !pl_par$rhs %in% c("dC", "svd_0"), ]), ]
- pl_par <- pl_par[!rownames(pl_par) %in% rownames(pl_par[pl_par$edge == "<->" & pl_par$rhs %in% c("treat"), ]), ]
- pl_mod@Pars <- pl_par
- plt <- semPaths(pl_mod, whatLabels = "est", residuals = FALSE, intStyle = "multi", sizeInt = 9, edge.label.cex = 1.2)
- plt$layout[1, ] <- c(-1, 0.6) #p.0
- plt$layout[2, ] <- c(-0.7, 0.6) #f.0
- plt$layout[3, ] <- c(-0.4, 0.6) #b.0
- plt$layout[4, ] <- c(0.2, 0.6) #p.1
- plt$layout[5, ] <- c(0.5, 0.6) #f.1
- plt$layout[6, ] <- c(0.8, 0.6) #b.1
- plt$layout[7, ] <- c(0.3, -1) #trt
- plt$layout[8, ] <- c(-0.7, 1.35) #age.c.0
- plt$layout[9, ] <- c(0.5, 1.35) #dufu
- plt$layout[10, ] <- c(-0.7, -0.5) #s_0
- plt$layout[11, ] <- c(0.5, -0.5) #s_1
- plt$layout[12, ] <- c(-0.2, -1) #dC
- plt$layout[13, ] <- c(-1.2, -0.5) #int.s_0
- plt$layout[14, ] <- c(-0.8, -1) #int.dC
- plt$graphAttributes$Nodes$labels <- c("Perive-\nticular\nWMH\nt0", "WM\nFree\nWater\nt0", "Basal\nganglia\nPVS\nt0",
- "Perive-\nticular\nWMH\nt1", "WM\nFree\nWater\nt1", "Basal\nganglia\nPVS\nt1",
- "Intensive\nBP\nControl",
- "Base-\nline\nage", "Follow\nup\ntime",
- "SVD\nt0", "SVD\nt1", "SVD\nChange",
- "Mean\nBaseline\nSVD", "Mean\nSVD\nChange")
- plt <- semptools::mark_sig(semPaths_plot = plt, object = fit1)
- plt$graphAttributes$Nodes$label.cex <- 1.6
- plt$graphAttributes$Edges$curve[c(24,25)] <- 0.5
- plt$graphAttributes$Edges$label.margin[c(16:18)] <- -0.035
- plt$graphAttributes$Edges$label.margin[c(21,23)] <- -0.04
- plt$graphAttributes$Edges$label.margin[c(22)] <- -0.03
- plt$plotOptions$label.prop <- c(1, 1, 1, 1, 1, 1, 0.95, 0.85, 0.85, 0.7, 0.7, 0.85, 0.45, 0.425)
- plt$graphAttributes$Edges$color[c(1,2,4,5,7,8)] <- "skyblue"
- plt$graphAttributes$Edges$color[c(3,6,9)] <- "navy"
- plt$graphAttributes$Edges$color[c(10:15)] <- "coral"
- plt$graphAttributes$Edges$color[c(16:18)] <- "lightgreen"
- plt$graphAttributes$Edges$color[c(21:22)] <- "blue"
- plt$graphAttributes$Edges$color[c(23)] <- "red2"
- plt$graphAttributes$Nodes$width <- c(5, 5, 5, 5, 5, 5, 7, 5, 5, 8, 8, 8, 12, 12)
- plot(plt)
- #//----- COMPUTE ADJUSTED TREATMENT EFFECT -----
- # LCS model with treatment arm as latent change score predictor adjusted for baseline age, sex, race, and icv
- model2 <-paste0('
- r_pvwml.0 ~ age.c.0
- r_pvwml.1 ~ age.c.0 + time_years.1
- r_fw.0 ~ age.c.0
- r_fw.1 ~ age.c.0 + time_years.1
- r_bgepvsc.0 ~ age.c.0
- r_bgepvsc.1 ~ age.c.0 + time_years.1
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw*r_fw.0 + bg*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw*r_fw.1 + bg*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ 0*1
- r_fw.0 ~ ifw*1
- r_bgepvsc.0 ~ ibg*1
- r_pvwml.1 ~ 0*1
- r_fw.1 ~ ifw*1
- r_bgepvsc.1 ~ ibg*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent change
- svd_1 ~ 1*svd_0
- dC =~ 1*svd_1
- # Latent variable mean structure
- svd_0 ~ a0*1 + age.c.0 + female + r_icv.0 + ', paste(c(race), collapse = " + "), '
- svd_1 ~ 0*1
- dC ~ 1 + a*treat + age.c.0 + female + r_icv.0 + ', paste(c(race), collapse = " + "), '
- # Latent variable covariance structure
- svd_0 ~~ svd_0
- svd_1 ~~ 0*svd_1
- dC ~~ b*dC
- dC ~~ svd_0
- # Standardized mean difference (Cohens d)
- cohen_d := a/sqrt(b)
- ')
- # Fit LCS model with Maximum Likelihood estimation method using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fit2 <- lavaan::sem(model2, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- summary(fit2, fit.measures = TRUE, standardized = TRUE)
- # Inspect fit indices
- fitmeasures(fit2, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- # Display parameter estimates of interest
- parameterEstimates(fit2)[parameterEstimates(fit2)$label %in%
- c("a", "cohen_d"),
- c("lhs", "est", "ci.lower", "ci.upper")]
- # Display latent change score variance
- parameterEstimates(fit2)[parameterEstimates(fit2)$label %in% "b", "est"]
- # Path diagram for the adjusted treatment effect (Figure 2; panel B)
- pl_mod <- semptools::drop_nodes(
- object = semPlotModel(fit2),
- nodes = c(race, "female", "r_icv.0"))
- pl_par <- pl_mod@Pars
- pl_par <- pl_par[!rownames(pl_par) %in% rownames(pl_par[pl_par$edge == "int" & !pl_par$rhs %in% c("dC", "svd_0"), ]), ]
- pl_par <- pl_par[!rownames(pl_par) %in% rownames(pl_par[pl_par$edge == "<->" & pl_par$rhs %in% c("treat"), ]), ]
- pl_mod@Pars <- pl_par
- plt <- semPaths(pl_mod, whatLabels = "est", residuals = FALSE, intStyle = "multi", sizeInt = 9, edge.label.cex = 1.2)
- plt$layout[1, ] <- c(-1, 0.6) #p.0
- plt$layout[2, ] <- c(-0.7, 0.6) #f.0
- plt$layout[3, ] <- c(-0.4, 0.6) #b.0
- plt$layout[4, ] <- c(0.2, 0.6) #p.1
- plt$layout[5, ] <- c(0.5, 0.6) #f.1
- plt$layout[6, ] <- c(0.8, 0.6) #b.1
- plt$layout[7, ] <- c(-0.7, 1.35) #age.c.0
- plt$layout[8, ] <- c(0.3, -1) #trt
- plt$layout[9, ] <- c(0.5, 1.35) #dufu
- plt$layout[10, ] <- c(-0.7, -0.5) #s_0
- plt$layout[11, ] <- c(0.5, -0.5) #s_1
- plt$layout[12, ] <- c(-0.2, -1) #dC
- plt$layout[13, ] <- c(-1.2, -0.5) #int.s_0
- plt$layout[14, ] <- c(-0.8, -1) #int.dC
- plt$graphAttributes$Nodes$labels <- c("Perive-\nticular\nWMH\nt0", "WM\nFree\nWater\nt0", "Basal\nganglia\nPVS\nt0",
- "Perive-\nticular\nWMH\nt1", "WM\nFree\nWater\nt1", "Basal\nganglia\nPVS\nt1",
- "Base-\nline\nage", "Intensive\nBP\nControl", "Follow\nup\ntime",
- "SVD\nt0", "SVD\nt1", "SVD\nChange",
- "Mean\nBaseline\nSVD", "Mean\nSVD\nChange")
- plt <- semptools::mark_sig(semPaths_plot = plt, object = fit2)
- plt$graphAttributes$Nodes$label.cex <- 1.6
- plt$graphAttributes$Edges$curve[c(22)] <- -6
- plt$graphAttributes$Edges$curve[c(26,27)] <- 0.5
- plt$graphAttributes$Edges$label.margin[c(16:18)] <- -0.035
- plt$graphAttributes$Edges$label.margin[c(21,23,24)] <- -0.04
- plt$graphAttributes$Edges$label.margin[c(23)] <- -0.03
- plt$graphAttributes$Edges$edge.label.position[25] <- 0.7
- plt$plotOptions$label.prop <- c(1, 1, 1, 1, 1, 1, 0.85, 0.95, 0.85, 0.7, 0.7, 0.85, 0.45, 0.425)
- plt$graphAttributes$Edges$color[c(1,2,4,5,7,8)] <- "skyblue"
- plt$graphAttributes$Edges$color[c(3,6,9)] <- "navy"
- plt$graphAttributes$Edges$color[c(10:15)] <- "coral"
- plt$graphAttributes$Edges$color[c(16:18)] <- "lightgreen"
- plt$graphAttributes$Edges$color[c(21,23)] <- "blue"
- plt$graphAttributes$Edges$color[c(24)] <- "red2"
- plt$graphAttributes$Edges$color[c(22, 25)] <- "magenta2"
- plt$graphAttributes$Nodes$width <- c(5, 5, 5, 5, 5, 5, 5, 7, 5, 8, 8, 8, 12, 12)
- plot(plt)
- #//----- COMPUTE TREATMENT EFFECT WITH ROI VOLUME-NORMALIZED SVD INDICATORS -----
- # LCS model with treatment arm as latent change score predictor (unadjusted) using ROI volume-adjusted MRI indicators
- model3 <-paste0('
- r_pvwmln.0 ~ age.c.0
- r_pvwmln.1 ~ age.c.0 + time_years.1
- r_fw.0 ~ age.c.0
- r_fw.1 ~ age.c.0 + time_years.1
- r_bgepvscn.0 ~ age.c.0
- r_bgepvscn.1 ~ age.c.0 + time_years.1
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwmln.0 + fw*r_fw.0 + bg*r_bgepvscn.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwmln.1 + fw*r_fw.1 + bg*r_bgepvscn.1
- # Mean structure specification
- r_pvwmln.0 ~ 0*1
- r_fw.0 ~ ifw*1
- r_bgepvscn.0 ~ ibg*1
- r_pvwmln.1 ~ 0*1
- r_fw.1 ~ ifw*1
- r_bgepvscn.1 ~ ibg*1
- # Residual covariances
- r_pvwmln.0 ~~ r_pvwmln.1
- r_fw.0 ~~ r_fw.1
- r_bgepvscn.0 ~~ r_bgepvscn.1
- # Latent change
- svd_1 ~ 1*svd_0
- dC =~ 1*svd_1
- # Latent variable mean structure
- svd_0 ~ a0*1
- svd_1 ~ 0*1
- dC ~ 1 + a*treat
- # Latent variable covariance structure
- svd_0 ~~ svd_0
- svd_1 ~~ 0*svd_1
- dC ~~ b*dC
- dC ~~ svd_0
- # Standardized mean difference (Cohens d) and % change relative to mean baseline SVD burden
- cohen_d := a/sqrt(b)
- prop := a/a0
- ')
- # Fit LCS model with Maximum Likelihood estimation method using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fit3 <- lavaan::sem(model3, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- summary(fit3, fit.measures = TRUE, standardized = TRUE)
- # Inspect fit indices
- fitmeasures(fit3, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- # Display parameter estimates of interest
- parameterEstimates(fit3)[parameterEstimates(fit3)$label %in%
- c("a", "cohen_d", "prop"),
- c("lhs", "est", "ci.lower", "ci.upper")]
- # Display latent change score variance
- parameterEstimates(fit3)[parameterEstimates(fit3)$label %in% "b", "est"]
- #//----- COMPUTE TREATMENT EFFECT IN ALL PARTICIPANTS WITH AVAILABLE BASELINE MRI WITH FIML -----
- # LCS model for the total sample of participants with baseline MRI with treatment arm as latent change score predictor (unadjusted) with fiml for missing follow-up MRI markers + auxiliary variables
- # Create dataset for fiml
- fiml <- wide0
- # Base auxiliary variable set
- base_set <- c('female', race, edu, polyph, smk, 'sub_cvd', 'sbp', 'dbp')
- # Inspect for missing values
- sapply(base_set, function(x){sum(is.na(fiml[ ,x]))})
- # Extended auxiliary variable set
- ext_set <- c("BMI", "HDL", "result_CO2", "egfr", "log2_umalcr", "lm_delayed1", "r_icv.0")
- # Inspect for missing values
- sapply(ext_set, function(x){sum(is.na(fiml[ ,x]))})
- # Fit LCS model with Full Information Maximum Likelihood estimation method with auxiliary variables using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fit.aux <- auxiliary(model1, aux = c(base_set, ext_set), fun = "sem", data = fiml, estimator = "ML", missing = "FIML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- summary(fit.aux, fit.measures = TRUE, standardized = TRUE)
- fitmeasures(fit.aux, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- parameterEstimates(fit.aux)[parameterEstimates(fit.aux)$label %in%
- c("a", "cohen_d", "prop"),
- c("lhs", "est", "ci.lower", "ci.upper")]
- #//-------------------------------------------- ANALYSES 3.4: ATTAINED SBP REDUCTION AND SVD CHANGE --------------------------------------------
- # LCS model with SBP delta group as latent change score predictor
- model4 <-paste0('
- r_pvwml.0 ~ age.c.0
- r_pvwml.1 ~ age.c.0 + time_years.1
- r_fw.0 ~ age.c.0
- r_fw.1 ~ age.c.0 + time_years.1
- r_bgepvsc.0 ~ age.c.0
- r_bgepvsc.1 ~ age.c.0 + time_years.1
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw*r_fw.0 + bg*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw*r_fw.1 + bg*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ 0*1
- r_fw.0 ~ ifw*1
- r_bgepvsc.0 ~ ibg*1
- r_pvwml.1 ~ 0*1
- r_fw.1 ~ ifw*1
- r_bgepvsc.1 ~ ibg*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent change
- svd_1 ~ 1*svd_0
- dC =~ 1*svd_1
- # Latent variable mean structure
- svd_0 ~ a0*1
- svd_1 ~ 0*1
- dC ~ 1 + a1*sbp_group_1 + a2*sbp_group_2 + a3*sbp_group_3
- # Latent variable covariance structure
- svd_0 ~~ svd_0
- svd_1 ~~ 0*svd_1
- dC ~~ dC
- dC ~~ svd_0
- # % change relative to mean baseline SVD burden
- prop_1 := a1/a0
- prop_2 := a2/a0
- prop_3 := a3/a0
- ')
- # Fit LCS model with Maximum Likelihood estimation method using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fit4 <- lavaan::sem(model4, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- summary(fit4, fit.measures = TRUE, standardized = TRUE)
- # Inspect fit indices
- fitmeasures(fit4, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- # Display parameter estimates of interest
- parameterEstimates(fit4)[parameterEstimates(fit4)$label %in%
- c("a1", "a2", "a3",
- "prop_1", "prop_2", "prop_3"),
- c("lhs", "est", "ci.lower", "ci.upper")]
- # Path diagram for different SBP delta groups and SVD burden change (Figure 3)
- pl_mod <- semPlotModel(fit4)
- pl_par <- pl_mod@Pars
- pl_par <- pl_par[!rownames(pl_par) %in% rownames(pl_par[pl_par$edge == "int" & !pl_par$rhs %in% c("dC", "svd_0"), ]), ]
- pl_par <- pl_par[!rownames(pl_par) %in% rownames(pl_par[pl_par$edge == "<->" & pl_par$rhs %in%
- c("sbp_group_1", "sbp_group_2", "sbp_group_3"), ]), ]
- pl_mod@Pars <- pl_par
- plt <- semPaths(pl_mod, whatLabels = "est", residuals = FALSE, intStyle = "multi", sizeInt = 9, edge.label.cex = 1.2)
- plt$layout[1, ] <- c(-1, 0.6) #p.0
- plt$layout[2, ] <- c(-0.7, 0.6) #f.0
- plt$layout[3, ] <- c(-0.4, 0.6) #b.0
- plt$layout[4, ] <- c(0.2, 0.6) #p.1
- plt$layout[5, ] <- c(0.5, 0.6) #f.1
- plt$layout[6, ] <- c(0.8, 0.6) #b.1
- plt$layout[7, ] <- c(0.8, -0.7) #sbp_1
- plt$layout[8, ] <- c(0.8, -1.0) #sbp_2
- plt$layout[9, ] <- c(0.8, -1.3) #sbp_3
- plt$layout[10, ] <- c(-0.7, 1.35) #age.c.0
- plt$layout[11, ] <- c(0.5, 1.35) #dufu
- plt$layout[12, ] <- c(-0.7, -0.5) #s_0
- plt$layout[13, ] <- c(0.5, -0.5) #s_1
- plt$layout[14, ] <- c(-0.2, -1) #dC
- plt$layout[15, ] <- c(-1.2, -0.5) #int.s_0
- plt$layout[16, ] <- c(-0.8, -1) #int.dC
- plt$graphAttributes$Nodes$labels <- c("Perive-\nticular\nWMH\nt0", "WM\nFree\nWater\nt0", "Basal\nganglia\nPVS\nt0",
- "Perive-\nticular\nWMH\nt1", "WM\nFree\nWater\nt1", "Basal\nganglia\nPVS\nt1",
- "SBP\nDrop\n0 to 10", "SBP\nDrop\n10 to 20", "SBP\nDrop\n≥ 20",
- "Base-\nline\nage", "Follow\nup\ntime",
- "SVD\nt0", "SVD\nt1", "SVD\nChange",
- "Mean\nBaseline\nSVD", "Mean\nSVD\nChange")
- plt <- semptools::mark_sig(semPaths_plot = plt, object = fit4)
- plt$graphAttributes$Nodes$label.cex <- 1.6
- plt$graphAttributes$Edges$curve[c(26,27)] <- 0.5
- plt$graphAttributes$Edges$label.margin[c(16:18)] <- -0.035
- plt$graphAttributes$Edges$label.margin[c(22, 23)] <- -0.02
- plt$graphAttributes$Edges$label.margin[c(21, 24, 25)] <- -0.03
- plt$plotOptions$label.prop <- c(1, 1, 1,
- 1, 1, 1,
- 0.9, 1, 0.9,
- 0.85, 0.85,
- 0.7, 0.7, 0.85,
- 0.45, 0.425)
- plt$graphAttributes$Edges$color[c(1,2,4,5,7,8)] <- "skyblue"
- plt$graphAttributes$Edges$color[c(3,6,9)] <- "navy"
- plt$graphAttributes$Edges$color[c(10:15)] <- "coral"
- plt$graphAttributes$Edges$color[c(16:18)] <- "lightgreen"
- plt$graphAttributes$Edges$color[c(21:22)] <- "blue"
- plt$graphAttributes$Edges$color[c(23:25)] <- "red2"
- plt$graphAttributes$Nodes$width <- c(5, 5, 5,
- 5, 5, 5,
- 5, 5, 5,
- 5, 5,
- 8, 8, 8,
- 12, 12)
- plot(plt)
- #//----- TREND TEST -----
- # LCS model with BP delta group as latent change score predictor - trend test
- model5 <-paste0('
- r_pvwml.0 ~ age.c.0
- r_pvwml.1 ~ age.c.0 + time_years.1
- r_fw.0 ~ age.c.0
- r_fw.1 ~ age.c.0 + time_years.1
- r_bgepvsc.0 ~ age.c.0
- r_bgepvsc.1 ~ age.c.0 + time_years.1
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw*r_fw.0 + bg*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw*r_fw.1 + bg*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ 0*1
- r_fw.0 ~ ifw*1
- r_bgepvsc.0 ~ ibg*1
- r_pvwml.1 ~ 0*1
- r_fw.1 ~ ifw*1
- r_bgepvsc.1 ~ ibg*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent change
- svd_1 ~ 1*svd_0
- dC =~ 1*svd_1
- # Latent variable mean structure
- svd_0 ~ 1
- svd_1 ~ 0*1
- dC ~ 1 + sbp_group_n
- # Latent variable covariance structure
- svd_0 ~~ svd_0
- svd_1 ~~ 0*svd_1
- dC ~~ dC
- dC ~~ svd_0
- ')
- # Fit LCS model with Maximum Likelihood estimation method using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fit5 <- lavaan::sem(model5, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- summary(fit5, fit.measures = TRUE, standardized = TRUE)
- # Inspect fit indices
- fitmeasures(fit5, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- # Extract parameter estimates of interest
- par <- parameterEstimates(fit5)
- par[par$lhs == "dC" & grepl("sbp_group_n", par$rhs),]
- #//-------------------------------------------- ANALYSES 3.4: BP MEDIATION OF THE TREATMENT ASSIGNMENT EFFECT --------------------------------------------
- # LCS model with treatment group as latent change score predictor and delta SBP as mediator
- model6 <-paste0('
- r_pvwml.0 ~ age.c.0
- r_pvwml.1 ~ age.c.0 + time_years.1
- r_fw.0 ~ age.c.0
- r_fw.1 ~ age.c.0 + time_years.1
- r_bgepvsc.0 ~ age.c.0
- r_bgepvsc.1 ~ age.c.0 + time_years.1
- # Measurement model for svd in time 0
- svd_0 =~ 1*r_pvwml.0 + fw*r_fw.0 + bg*r_bgepvsc.0
- # Measurement model for svd in time 1
- svd_1 =~ 1*r_pvwml.1 + fw*r_fw.1 + bg*r_bgepvsc.1
- # Mean structure specification
- r_pvwml.0 ~ 0*1
- r_fw.0 ~ ifw*1
- r_bgepvsc.0 ~ ibg*1
- r_pvwml.1 ~ 0*1
- r_fw.1 ~ ifw*1
- r_bgepvsc.1 ~ ibg*1
- # Residual covariances
- r_pvwml.0 ~~ r_pvwml.1
- r_fw.0 ~~ r_fw.1
- r_bgepvsc.0 ~~ r_bgepvsc.1
- # Latent change
- svd_1 ~ 1*svd_0
- dC =~ 1*svd_1
- # Latent variable mean structure
- svd_0 ~ 1
- svd_1 ~ 0*1
- sbp_delta ~ a*treat
- dC ~ 1 + b*sbp_delta + c*treat
- # Latent variable covariance structure
- svd_0 ~~ svd_0
- svd_1 ~~ 0*svd_1
- dC ~~ dC
- dC ~~ svd_0
- Indirect := a*b
- Direct := c
- Total := (a*b) + c
- ')
- # Fit LCS model with Maximum Likelihood estimation method using robust (Huber-White) standard errors and a scaled (Yuan-Bentler) test statistic
- fit6 <- lavaan::sem(model6, data = wide01, estimator = "ML", se = "robust.huber.white", test = "yuan.bentler.mplus")
- summary(fit6, fit.measures = TRUE, standardized = TRUE)
- # Inspect fit indices
- fitmeasures(fit6, fit.measures = c("chisq.scaled", "pvalue.scaled",
- "cfi.robust", "rmsea.robust", "srmr"))
- # Extract parameter estimates of interest
- parameterEstimates(fit6)[parameterEstimates(fit6)$op %in% ":=",
- c("lhs", "est", "ci.lower", "ci.upper")]
- # Path diagram of indirect (through delta SBP) and direct treatment effect (Supplemental Figure 3)
- pl_mod <- semPlotModel(fit6)
- pl_par <- pl_mod@Pars
- pl_par <- pl_par[!rownames(pl_par) %in% rownames(pl_par[pl_par$edge == "int" & !pl_par$rhs %in% c("dC", "svd_0"), ]), ]
- pl_par <- pl_par[!rownames(pl_par) %in% rownames(pl_par[pl_par$edge == "<->" & pl_par$rhs %in%
- c("sbp_delta", "treat"), ]), ]
- pl_mod@Pars <- pl_par
- plt <- semPaths(pl_mod, whatLabels = "est", residuals = FALSE, intStyle = "multi", sizeInt = 9, edge.label.cex = 1.2)
- plt$layout[1, ] <- c(-1, 0.6) #p.0
- plt$layout[2, ] <- c(-0.7, 0.6) #f.0
- plt$layout[3, ] <- c(-0.4, 0.6) #b.0
- plt$layout[4, ] <- c(0.2, 0.6) #p.1
- plt$layout[5, ] <- c(0.5, 0.6) #f.1
- plt$layout[6, ] <- c(0.8, 0.6) #b.1
- plt$layout[7, ] <- c(0.8, -0.7) #delta_sbp
- plt$layout[8, ] <- c(0.8, -1.3) #treat
- plt$layout[9, ] <- c(-0.7, 1.35) #age.c.0
- plt$layout[10, ] <- c(0.5, 1.35) #dufu
- plt$layout[11, ] <- c(-0.7, -0.5) #s_0
- plt$layout[12, ] <- c(0.5, -0.5) #s_1
- plt$layout[13, ] <- c(-0.2, -1) #dC
- plt$layout[14, ] <- c(-1.2, -0.5) #int.s_0
- plt$layout[15, ] <- c(-0.8, -1) #int.dC
- plt$graphAttributes$Nodes$labels <- c("Perive-\nticular\nWMH\nt0", "WM\nFree\nWater\nt0", "Basal\nganglia\nPVS\nt0",
- "Perive-\nticular\nWMH\nt1", "WM\nFree\nWater\nt1", "Basal\nganglia\nPVS\nt1",
- "\u0394SBP", "Intensive\nBP\nControl",
- "Base-\nline\nage", "Follow\nup\ntime",
- "SVD\nt0", "SVD\nt1", "SVD\nChange",
- "Mean\nBaseline\nSVD", "Mean\nSVD\nChange")
- plt <- semptools::mark_sig(semPaths_plot = plt, object = fit6)
- plt$graphAttributes$Nodes$label.cex <- 1.6
- plt$graphAttributes$Edges$curve[c(26,27)] <- 0.5
- plt$graphAttributes$Edges$label.margin[c(16:18)] <- -0.035
- plt$graphAttributes$Edges$label.margin[c(21)] <- -0.03
- plt$graphAttributes$Edges$label.margin[c(23)] <- -0.02
- plt$graphAttributes$Edges$label.margin[c(24)] <- -0.02
- plt$plotOptions$label.prop <- c(1, 1, 1,
- 1, 1, 1,
- 0.9, 0.95,
- 0.85, 0.85,
- 0.7, 0.7, 0.85,
- 0.45, 0.425)
- plt$graphAttributes$Edges$color[c(1,2,4,5,7,8)] <- "skyblue"
- plt$graphAttributes$Edges$color[c(3,6,9)] <- "navy"
- plt$graphAttributes$Edges$color[c(10:15)] <- "coral"
- plt$graphAttributes$Edges$color[c(16:18)] <- "lightgreen"
- plt$graphAttributes$Edges$color[c(21,23)] <- "blue"
- plt$graphAttributes$Edges$color[c(22,24)] <- "red2"
- plt$graphAttributes$Nodes$width <- c(5, 5, 5,
- 5, 5, 5,
- 5, 5,
- 5, 5,
- 8, 8, 8,
- 12, 12)
- plot(plt)
- # Bootstrapped solution
- # Detect cpu number
- ncpus = max(1, parallel::detectCores() - 1)
- # Fit LCS model with Maximum Likelihood estimation method using bootstrapped standard errors and a scaled (Yuan-Bentler) test statistic
- fit6_boot <- lavaan::sem(model6, data = wide01, estimator = "ML", test = "yuan.bentler.mplus",
- se = "bootstrap", bootstrap = 5000, parallel = "snow",
- ncpus = ncpus, iseed = 2025)
- # Extract parameter estimates of interest from bootstrapped solution
- sum <- parameterEstimates(fit6_boot)
- sum <- sum[sum$op == ":=" , c("label", "est", "ci.lower", "ci.upper", "pvalue")]
- rownames(sum) <- sum[,"label"]
- sum <- sum[ ,-1]
- sum
- #//--------------------------------------------------------------------------- END OF ANALYTIC CODE ---------------------------------------------------------------------------//
SVD_SPRINT_Git_20260705.R at commit ce6d95d, no license · at the source
Overview
- Neuroimage Analytics Laboratory (NAL) and the Biggs Institute Neuroimaging Core (BINC), Glenn Biggs Institute for Alzheimer's and Neurodegenerative Diseases, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
- Department of Biostatistics and Data Science, Wake Forest University School of Medicine, Winston-Salem, NC, USA
- Department of Psychiatry and Behavioral Sciences, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Neurology, UCLA David Geffen School of Medicine, Los Angeles, CA, USA
- Neuroepidemiology Section, Intramural Research Program, National Institute on Aging, Bethesda, MD, USA
- Section of Gerontology and Geriatric Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, USA
Abstract
Background: The benefits of improved systolic blood pressure (SBP) control on stroke, coronary heart disease, and heart failure are well-established, yet its effect on overall cerebral small vessel disease (SVD) burden remains uncharacterized. We examined the association between intensive SBP control and change in SVD burden.
Methods: We conducted a post-hoc analysis of the Systolic Blood Pressure Intervention Trial (SPRINT), a multicenter randomized clinical trial. Of 1267 hypertensive individuals aged ≥50 years without diabetes or prior stroke screened for the brain MRI substudy, 663 and 442 participants completed brain MRI that met quality control criteria and had complete data on SVD indicators at baseline and at a median of 3.9 (interquartile range, 3.6–4.1) years after randomization, respectively. From November 2010 to March 2013, participants were randomly assigned to an intensive SBP target of <120 mmHg (n = 348) or a standard target of <140 mmHg (n = 315). Post-hoc outcome was change in a global SVD factor, longitudinally validated using confirmatory factor analysis and designed to capture overall SVD-related vascular brain injury by integrating three complementary imaging endophenotypes: periventricular white matter hyperintensities, white matter free water, and basal ganglia perivascular spaces. This trial is registered with ClinicalTrials.gov (NCT01206062).
Findings: Mean [SD] baseline age was 68.1 (8.6) years; 263 [40%] participants were women. Compared with standard SBP treatment, intensive treatment was associated with significantly less SVD progression (standardized mean difference [Cohen's d] = −0.40 [95% CI, −0.62 to −0.17]). We also observed gradually more favorable SVD burden changes with greater attained SBP reductions, demonstrating a clear dose–response relationship: 21.2% (95% CI, 7.4%–35%), 26.3% (13.1%–39.5%), and 39.4% (24.2%–54.5%) less progression relative to baseline SVD burden for SBP reductions of 0–10 mmHg, 10–20 mmHg, and ≥20 mmHg, respectively.
Interpretation: Among hypertensive adults, targeting an SBP of <120 mmHg, compared with <140 mmHg, was associated with less progression of SVD burden. Even modest SBP reductions of ≤10 mmHg conferred measurable brain benefits, with larger reductions providing incrementally greater protection against SVD progression.
Funding: National Institutes of Health, National Heart, Lung, and Blood Institute, National Institute of Diabetes and Digestive and Kidney Diseases, National Institute on Aging, and National Institute of Neurological Disorders and Stroke.
Reproduced under the paper's license (CC BY), from the paper cited above.
Repository
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UTHSCSA-NAL/SPRINT_SVD
ce6d95d69bd81a9f15cb1cffdd7011a7fdb14290, 5 July 2026Availability: 1 check, the latest on 27 September 2026: the link answers
- 27 September 2026: the link answers
2 files
- SVD_SPRINT_Git_20260705.
R , R, 1,639 lines, 7 matches - README.md, Text, 6 lines
The paper's code and data availability statement is in the Data section.
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Reproduced under the paper's license (CC BY), from the paper cited above.
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Version 3, 28 September 2026
- Authors: added Tanweer Rashid (0000-0001-6844-9558); Niyas Shamsudeen Kutty (0000-0001-5511-4249); Kyle C. Kern (0000-0002-2703-7669); Lenore Launer (0000-0002-3238-7612); Mohamad Habes (0000-0001-9447-5805); removed Tanweer Rashid; Niyas Shamsudeen Kutty; Kyle C. Kern; Lenore Launer; Mohamad Habes
Version 1, 27 September 2026: the first record
Recorded: type, language, journal, volume, pages, dates, 17 authors, 7 keywords, 25 funders, 36 references.
Cite
This paper
Charisis, S., Pajewski, N. M., Price, L. R., Ho, N. H., Rashid, T., Wang, D., Zeng, Y., Kutty, N. S., Bryan, R. N., Kern, K. C., Dickerson, B. C., Seshadri, S., Nasrallah, I., Launer, L., Davatzikos, C., Williamson, J. D., & Habes, M. (2026). Intensive versus standard blood pressure control and overall brain small vessel disease burden: a post-hoc analysis of the SPRINT randomized clinical trial. EClinicalMedicine, 99, 104143. https://
BibTeX
@article{charisis2026int
author = {Charisis, Sokratis and Pajewski, Nicholas M. and Price, Larry R. and Ho, Ngoc Huynh and Rashid, Tanweer and Wang, David and Zeng, Yuheng and Kutty, Niyas Shamsudeen and Bryan, R. Nick and Kern, Kyle C. and Dickerson, Bradford C. and Seshadri, Sudha and Nasrallah, Ilya and Launer, Lenore and Davatzikos, Christos and Williamson, Jeff D. and Habes, Mohamad},
title = {{Intensive versus standard blood pressure control and overall brain small vessel disease burden: a post-hoc analysis of the SPRINT randomized clinical trial}},
journal = {EClinicalMedicine},
year = {2026},
month = aug,
volume = {99},
pages = {104143},
publisher = {Elsevier},
issn = {2589-5370},
doi = {10.1016/
url = {https://
pmid = {42614618},
pmcid = {PMC13482511}
}
RIS
TY - JOUR
AU - Charisis, Sokratis
AU - Pajewski, Nicholas M.
AU - Price, Larry R.
AU - Ho, Ngoc Huynh
AU - Rashid, Tanweer
AU - Wang, David
AU - Zeng, Yuheng
AU - Kutty, Niyas Shamsudeen
AU - Bryan, R. Nick
AU - Kern, Kyle C.
AU - Dickerson, Bradford C.
AU - Seshadri, Sudha
AU - Nasrallah, Ilya
AU - Launer, Lenore
AU - Davatzikos, Christos
AU - Williamson, Jeff D.
AU - Habes, Mohamad
TI - Intensive versus standard blood pressure control and overall brain small vessel disease burden: a post-hoc analysis of the SPRINT randomized clinical trial
T2 - EClinicalMedicine
J2 - eClinicalMedicine
PY - 2026
DA - 2026/
VL - 99
SP - 104143
SN - 2589-5370
PB - Elsevier
DO - 10.1016/
UR - https://
LA - en
ER -
CSL-JSON
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