Antihypertensive Medications May Lower Dementia Risk in Late Life

The risk of developing dementia is lower among older adults who continue to take antihypertensives compared with those with untreated hypertension, according to a meta-analysis published in JAMA Network Open.

While hypertension is among one of the most prevalent risk factors for dementia, studies have shown that this association is not consistent in late life. Other studies have shown a protective effect of higher blood pressure against dementia. 

Researchers conducted an individual participant data (IPD) meta-analysis to determine the association between dementia and a history of hypertension, antihypertensive medication use, and baseline blood pressure in late life.

The researchers identified 17 longitudinal, population-based studies from the Cohort Studies of Memory in an International Consortium (COSMIC). A total of 34,519 participants from in 16 different countries were identified. Follow-up duration (range, 2-15 years) and assessment schedules varied per study.

The primary outcome was all-cause dementia, and most studies used the diagnosis criteria listed in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV).

The average age at baseline was 72.5 (standard deviation [SD], 7.5) and 58.4% were women. The researchers excluded 2884 participants with dementia from analysis at baseline. 

At the start of the study, the average systolic blood pressure was 138.7 mmHg (SD, 21.5 mmHg) and diastolic blood pressure was 80.2 mmHg (SD, 11.3 mmHg). 

There were 14 studies that reported a higher risk for dementia among participants with untreated hypertension when compared to healthy control group participants (hazard ratio [HR], 1.42; 95% CI, 1.15-1.76; P =.001). In addition, compared with participants treated for hypertension, those with untreated hypertension had a higher risk for dementia (HR, 1.26; 95% CI, 1.03-1.54; P =.03).

There were no significant differences in risk between participants treated for hypertension compared with healthy control individuals (HR, 1.13; 95% CI, 0.99-1.28; P =.07). The fully adjusted analysis of 9 studies revealed similar results, but the analysis only extended to 5 years of follow up. 

Treated hypertension was associated with an increased risk for dementia at ages 60-70 but not at ages 80-90.

There were no significant associations between baseline systolic or diastolic blood pressure and dementia risk. Moreover, there were no significant associations reported among different subgroups based on age, sex, or race. 

“Our study, in combination with these results, provides the strongest data yet for the importance of antihypertensive use even in late life and that more than a single late-life blood pressure [BP] measure is needed to guide risk stratification and treatment decisions,” the researchers noted.

The researchers concluded, “Antihypertensive use was associated with decreased dementia risk in late-life individuals with hypertension; thus, dementia risk reduction may be 1 of the multiple goals of antihypertensive treatment in late-life (eg, prevention of ischemic heart disease, chronic kidney disease).”

Study limitations include variability in study design, changes in definitions of hypertension, and lack of data regarding competing events to dementia, such as stroke. 

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.