Abstract Body: Introduction: Midlife hypertension might increase a person's risk of dementia and cognitive decline, but lacks in evidence. Cerebrovascular consequences of chronic hypertension are well-documented, it is unclear, if treating high blood pressure (BP) stops cognitive problems. To better understand how hypertension leads to cognitive decline, we researched and evaluated how using antihypertensive drugs affects the brain.
Hypothesis: Intensive antihypertensive therapy aimed at keeping systolic BP below 115 mmHg during middle age (45-65) is more effective in protecting the brain than standard care (keeping it below 140 mmHg). The most significant cognitive protection is observed when this treatment is used for at least 10 years before a person turns 70, as it preserves the structure of brain micro vessels.
Methods: PRISMA guidelines were followed to examin how BP or hypertension influences people's cognitive functions. Only 24 studies met the requirements (nine RCTs and fifteen observational studies). We documented the links between raised BP and mental decline, an increase in dementia risk, and how lowering BP supports the mind. We evaluated RCTs using Cochrane's Risk of Bias tool and observational studies with Newcastle-Ottawa Scale.
Results: Having high BP in midlife led to a faster decline in thinking and a greater risk of dementia. Cohorts studies have confirmed people with hypertension over a long period had increased mental decline than individuals with normal BP. Experimental blood pressure control (such as with systolic <120) appeared to decrease mild cognitive impairment and best preserve thinking skills compared to standard levels. It was difficult to measure the impact of dementia on the limited follow-up time in studies. Studies have reported no benefits and some benefits for cognitive functions from treating high BP. Association studies had high evidence quality, while trial data were moderate because of differences in conducting cognitive assessments.
Conclusions: This review identified a knowledge gap by bringing together evidence on the relationship between hypertension and cognitive decline. Evidence suggests that, in midlife, high BP can be modified to help prevent cognitive impairment. Besides, lowering BP very aggressively might help the brain, but the degree to which it slows the development of dementia is not yet known. The results shows controlling BP early matters and encourage more research on how it affects cognitive functions.