A new analysis of 12 randomized clinical trials is shedding more definitive light on the impact of antihypertensive agents on risk of dementia and cognitive decline.
While lowering blood pressure is essential to living a healthier life for many patients, a new study suggests treating hypertension could also reduce a patient’s risk of developing dementia.
Examining data from a dozen trials, results of the systematic review and meta-analysis indicate blood pressure lowering with antihypertensive medications reduced an individual’s risk of developing dementia or cognitive impairment by 7%.
"Prevention of dementia is a major health priority. We know from previous research that a major concern of older people is developing dementia. The message from this study is simple: Get your blood pressure checked,” said Michelle Canavan, consultant geriatrician at Galway University Hospital, in a statement. “If it is high, it can be readily treated with lifestyle changes and medications. We would hope that our study will heighten awareness of the importance of controlling blood pressure to maintain "brain" health, combined with a healthy lifestyle."
With previous studies drawing conflicting conclusions in regard to the impact of blood pressure lowering on risk of dementia and cognitive decline, Canavan and a team of colleagues from the National University of Ireland, Galway sought to determine whether treating hypertension could benefit neurocognitive function. To do so, they designed the current systematic review and meta-analysis to examine data from the PubMed, EMBASE, and CENTRAL databases from inception through 2019.
Investigators searched the 3 databases for studies including the terms dementia, cognitive decline, cognitive impairment, blood pressure, hypertension, anti-hypertensive, and randomized clinical trials. The primary outcome of the trial was dementia or cognitive repair. Secondary outcomes were cognitive decline and changes in cognitive test scores.
For inclusion, trials needed to compare blood pressure lowering with antihypertensive agents against a control, have at least 1 year of follow-up, include more than 1000 participants, and be designed as randomized clinical trials. Trials were also required to report outcomes related to dementia, cognitive impairment, cognitive decline, or change in cognitive test scores. In total, 14 studies met inclusion criteria.
Of note, only 12 studies reported the incidence of dementia or cognitive and were included in the primary analysis. All 14 studies were used to examine secondary outcomes.
From the 14 studies identified for inclusion, investigators obtained data on 96,158 individuals with 394,558 years of follow-up data—mean length of follow-up was 49.24 (26.4-68.4) months. The mean age of participants was 69 (5.4) years and 42.2% were women. In regard to baseline characteristics, the mean systolic blood pressure was 154 (14.9) mmHg and mean diastolic blood pressure was 83.3 (9.9) mmHg.
In 12 trials examining dementia or cognitive impairment, results indicated blood pressure lowering with antihypertensive agents was significantly associated with a reduced risk of dementia or cognitive impairment (7.0% vs 7.5%, mean trial follow-up of 4.1 years; odds ratio [OR], 0.93 [95% CI, 0.88-0.98]; absolute risk reduction, 0.39% [95% CI, 0.09%-0.68%]; I2=0.0%) when compared against controls. In an analysis of 8 trials examining cognitive decline, results indicated blood pressure lowering with antihypertensive agents was significantly associated with reduced risk of cognitive decline (20.2% vs 21.1%, mean trial follow-up of 4.1 years; OR, 0.93 [95% CI, 0.88-0.99]; absolute risk reduction, 0.71% [95% CI, 0.19%-1.2%]; I2 = 36.1%) when compared against controls.
This study, “Association of Blood Pressure Lowering With Incident Dementia or Cognitive Impairment: A Systematic Review and Meta-analysis,” was published in the Journal of the American Medical Association.