Treating hypertension helps lower dementia risk in older adults

Older adults with hypertension who are on blood pressure (BP)-lowering medications are better protected against dementia than those with untreated hypertension, and this is true across all ages in late life, according to an individual participant data meta-analysis.

Pooled data from 14 studies showed that the risk of dementia in participants >60 years of age with untreated hypertension was 42-percent higher than in healthy controls (hazard ratio [HR], 1.42; 95 percent confidence interval [CI], 1.15–1.76; p=0.001) and 26-percent higher than in participants with treated hypertension (HR, 1.26;, 95 percent CI, 1.03–1.53; p=0.02). [JAMA Netw Open  2023;6:e2333353]

“[E]ven at the ages of 70 and 80 years, there was a significantly higher dementia risk in individuals with untreated hypertension compared with the treated hypertension group,” the investigators noted.

For participants with treated hypertension, on the other hand, their risk of dementia throughout late life was no higher than that of healthy controls (HR, 1.13; 95 percent CI, 0.99–1.28; p=0.07). This result was consistent across all ages, sexes, and races.

Baseline systolic BP and diastolic BP, regardless of age, were not associated with dementia risk, nor did they significantly modify the association of hypertension and antihypertensive use status with dementia risk.

“Our findings indicate that baseline BP, being a cross-sectional snapshot of a highly variable biomarker, is of limited significance when making decisions to continue antihypertensive treatment for dementia risk reduction,” the investigators said. “Corroborating extant hypertension guidelines, it seems that more than one [BP] measure is needed to inform treatment.” [Int J Geriatr Psychiatry 2009;24:509-517; Hypertension 2018;71:e13-e115]

The present study provides the strongest data yet for the importance of antihypertensive use even in late life, they added. The takeaway is that lowering the risk of dementia may be another reason to treat hypertension in older adults, in addition to preventing other serious health problems such as ischaemic heart disease and chronic kidney disease.

A total of 17 studies were included in the meta-analysis. These studies were conducted in 15 different countries, including US, Brazil, Australia, China, Korea, Singapore, Central African Republic, Republic of Congo, Nigeria, Germany, Spain, Italy, France, Sweden, and Greece.

The study population comprised 34,519 participants aged 60–110 years (mean age at baseline, 72.5 years; women, 58.4 percent), and the mean follow-up time was 4.3 years. They had a mean 8.2 years of education, and the mean systolic/diastolic BP was 138.7/80.2 mm Hg.

Of the participants, 10,402 (35.5 percent) were healthy controls, 14,759 (50.3 percent) had treated hypertension, and 2,881 (9.8 percent) had untreated hypertension. The average time to dementia diagnosis was about 4 years, although this varied considerably by study.