Background Research links blood pressure variability ( BPV ) with stroke; however, the association with cerebral small‐vessel disease ( CSVD ) remains unclear. As BPV and mean blood pressure are interrelated, it remains uncertain whether BPV adds additional information to understanding cerebrovascular morphological characteristics. Methods and Results A systematic review was performed from inception until March 3, 2019. Eligibility criteria included population, adults without stroke (<4 weeks); exposure, BPV quantified by any metric over any duration; comparison, (1) low versus high or mean BPV and (2) people with versus without CSVD ; and outcomes, (1) CSVD as subcortical infarct, lacunae, white matter hyperintensities, cerebral microbleeds, or enlarged perivascular spaces; and (2) standardized mean difference in BPV . A total of 27 articles were meta‐analyzed, comprising 12 309 unique brain scans. A total of 31 odds ratios ( OR s) were pooled, indicating that higher systolic BPV was associated with higher odds for CSVD ( OR, 1.27; 95% CI, 1.14–1.42; I 2 =85%) independent of mean systolic pressure. Likewise, higher diastolic BPV was associated with higher odds for CSVD ( OR, 1.30; 95% CI, 1.14–1.48; I 2 =53%) independent of mean diastolic pressure. There was no evidence of a pairwise interaction between systolic/diastolic and BPV /mean OR s ( P =0.47), nor a difference between BPV versus mean pressure OR s ( P =0.58). Fifty‐four standardized mean differences were pooled and provided similar results for pairwise interaction ( P =0.38) and difference between standardized mean differences ( P =0.70). Conclusions On the basis of the available studies, BPV was associated with CSVD independent of mean blood pressure. However, more high‐quality longitudinal data are required to elucidate whether BPV contributes unique variance to CSVD morphological characteristics.
IMPORTANCEThe optimal systolic blood pressure (SBP) to minimize the risk of dementia in older age is unknown.OBJECTIVE To investigate whether the association between SBP and dementia risk is U-shaped and whether age and comorbidity play a role in this association. DESIGN, SETTING, AND PARTICIPANTSThis cohort study used an individual participant data approach to analyze 7 prospective, observational, population-based cohort studies that were designed to evaluate incident dementia in older adults. These studies started between 1987 and 2006 in Europe and the US. Participants had no dementia diagnosis and had SBP and/or diastolic blood pressure (BP) data at baseline and incident dementia status during follow-up. Data analysis was conducted from November 7, 2019, to October 3, 2021.EXPOSURES Baseline systolic BP. MAIN OUTCOMES AND MEASURES All-cause dementia (defined using Diagnostic and Statistical Manual of Mental Disorders [Third Edition Revised] or Diagnostic and Statistical Manual of Mental Disorders [Fourth Edition] and established at follow-up measurements or in clinical practice), mortality, and combined dementia and mortality were the outcomes. Covariates included baseline antihypertensive medication use, sex, educational level, body mass index, smoking status, diabetes, stroke history, myocardial infarction history, and polypharmacy. Cox proportional hazards regression models were used, and nonlinear associations were explored using natural splines. RESULTSThe study analyzed 7 cohort studies with a total of 17 286 participants, among whom 10 393 were women (60.1%) and the mean (SD) baseline age was 74.5 (7.3) years. Overall, dementia risk was lower for individuals with higher SBP, with the lowest risk associated with an SBP of approximately 185 mm Hg (95% CI, 161-230 mm Hg; P = .001). Stratified by overlapping 10-year baseline age groups, the lowest dementia risk was observed at somewhat lower systolic BP levels in those older than 75 years (158 [95% CI, mm Hg to 170 [95% CI, 160-260] mm Hg). For mortality, there was a clear U-shaped association, with the lowest risk at 160 mm Hg (95% CI, 154-181 mm Hg; P < .001). This U-shape occurred across all age groups, with the lowest dementia risk associated with an SBP of 134 mm Hg (95% CI, 102-149 mm Hg; P = .03) in those aged 60 to 70 years and increasing to between 155 mm Hg (95% CI, 150-166 mm Hg; P < .001) and 166 mm Hg (95% CI, 154-260 mm Hg; P = .02) for age groups between 70 and 95 years. Combined dementia and mortality risk curves closely resembled those for mortality. Associations of diastolic BP with dementia risk were generally similar but were less distinct.CONCLUSIONS AND RELEVANCE This cohort study found that dementia risk was lower for older individuals with higher SBP levels and that more distinctly U-shaped associations appeared for those older than 75 years, but these associations cannot be explained by SBP-associated changes in mortality risk. The findings may warrant future trials on tailored BP management in older age groups that take life expec...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.