Blood Pressure Lowering and Prevention of Dementia

Quick Takes

  • Uncertainty has existed about whether blood pressure (BP) reduction reduces the risk of incident dementia.
  • This study is an individual patient-level pooled analysis of five randomized controlled trials of BP lowering versus placebo with incident dementia as an outcome.
  • Across almost 30,000 participants, BP lowering was associated with a decreased risk of incident dementia, a finding which has huge public health implications.

Study Questions:

Does blood pressure (BP) reduction lower the risk of incident dementia?

Methods:

This is a pooled analysis of five large, randomized, placebo-controlled trials of BP lowering using individual patient-level data from 28,008 participants who were free of dementia or serious cognitive loss at baseline. Incident all-cause dementia was the primary outcome. Multilevel logistic regression was used for the primary analysis. Possible interactions (effect modification) by age, baseline Miniā€Mental State Examination (MMSE), sex, prior stroke, and baseline systolic BP (SBP) were investigated.

Results:

The mean age of the participants was 69.1 years (standard deviation, 9.3 years) and 46.8% were female. Over a median follow-up of 4.3 years, BP-lowering treatment compared to placebo was associated with a lower risk of incident dementia (odds ratio, 0.868; 95% confidence interval, 0.756-0.996). This result was essentially unchanged after adjustment for age, sex, history of stroke, body mass index, diabetes, and educational level. No interaction was observed by age, baseline MMSE, sex, prior stroke, or baseline SBP.

Conclusions:

The authors concluded that BP reduction lowers the risk of incident dementia in an older population.

Perspective:

Studies that seek to investigate incident dementia as an outcome are expensive and resource-intensive because of the necessary long duration of follow-up. This meta-analysis used already available patient-level data to evaluate the effect of BP lowering on incident dementia. The results of this study will be practice- and guideline-changing. Given no meaningful available treatment for dementia, any intervention that can reduce its incidence has huge public health and economic implications. Best of all, the examined intervention—BP lowering—is generalizable, affordable, and has additional benefits in reducing adverse cardiovascular outcomes.

Clinical Topics: Geriatric Cardiology, Prevention, Sleep Apnea

Keywords: Blood Pressure, Body Mass Index, Cognition, Dementia, Diabetes Mellitus, Geriatrics, Primary Prevention, Public Health, Risk Factors, Stroke


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