Can Antihypertensive Medication Reduce Dementia Risk in Older Adults?

LONDON—Calcium channel blockers and angiotensin receptor blockers are independently associated with a decreased risk of dementia in older patients, according to a study presented at the 2017 Alzheimer’s Association International Conference and published in the October issue of Journal of Hypertension.

“Calcium channel blockers regulate calcium influx, which may prevent neuronal cell death, inhibit the production of amyloid beta and neurofibrillary tangles, and improve cerebrovascular perfusion. Angiotensin receptor blockers may improve the cerebral blood flow, decrease levels of amyloid beta, and have an anti-inflammatory effect,” said Tessa van Middelaar, MD, a PhD student in the Department of Neurology at the Academic Medical Center in Amsterdam and the Radboud University Medical Center in Nijmegen.

Tessa van Middelaar, MD

Epidemiologic evidence has suggested that hypertension is an important risk factor for dementia. Trials studying the effect of antihypertensive medication on the incidence of dementia have had inconclusive results, however.

Post Hoc Analysis of Data

Dr. van Middelaar and colleagues conducted a post hoc analysis of data from the Prevention of Dementia by Intensive Vascular Care (preDIVA) trial. In this randomized controlled trial, 3,526 community-dwelling adults ranging in age from 70 to 78 received either intensive vascular care or standard care.

At baseline and during follow-up, data on medication use and medical history were collected every two years. Researchers identified five classes of antihypertensive medication used by participants (ie, beta-blockers, diuretics, ACE inhibitors, calcium channel blockers, and angiotensin receptor blockers).

The investigators used the Mini-Mental State Examination to measure cognition and defined dementia using the Diagnostic and Statistical Manual of Mental Disorders IV criteria. Analyses were restricted to participants who were using antihypertensive medications at baseline. Dr. van Middelaar and colleagues compared incident dementia rates associated with the use of different antihypertensive medication classes, including monotherapy and combination therapy, with those associated with any other antihypertensive medication. They used a Cox proportional hazards regression model to analyze the association between antihypertensive treatment and dementia incidence rate.

Two Classes Reduced Dementia Risk

At baseline, 1,951 patients used antihypertensive medication. The study population’s mean age was 74.4, and 46.2% of participants were men. In all, 986 patients used beta-blockers, 798 used diuretics, 623 used ACE inhibitors, 522 used calcium channel blockers, and 402 used angiotensin receptor blockers. After a median of 6.7 years of follow-up, 136 participants developed dementia.

The use of calcium channel blockers and the use of angiotensin receptor blockers were associated with a lower incidence of dementia, compared with the use of other antihypertensive medications (hazard ratios, 0.56 and 0.60, respectively). The reduced risk of dementia associated with calcium channel blockers was the most evident in participants without a history of cardiovascular disease and those with uncontrolled hypertension. “A possible explanation for this increased benefit in older people without a history of cardiovascular disease could be related to less pronounced vascular lesions and, therefore, more brain reserve and capacity for functional resilience to cognitive decline,” said Dr. van Middelaar and colleagues. Researchers also found that systolic blood pressure was not significantly lower in participants using calcium channel blockers or angiotensin receptor blockers.

—Erica Tricarico

Suggested Reading

van Middelaar T, van Vught LA, Moll van Charante EP, et al. Lower dementia risk with different classes of antihypertensive medication in older patients. J Hypertens. 2017;35(10):2095-2101.