Calcium channel blocker use reduces incident dementia risk in elderly hypertensive patients: A meta-analysis of prospective studies

Calcium channel blockers (CCBs) are an established class of drug for the management of hypertension. Observational studies have found that CCB use is associated with a reduction in the risk of developing dementia; however, studies have variably linked the CCBs use with the risk of dementia. This meta-analysis aims to assess whether, in elderly hypertensive patients, the use of CCBs alters the risk of developing dementia. We searched PubMed, Embase and Cochrane from August 2013 to 21st August 2017. Studies were screened on the basis of title and abstract. Quality of the included studies was assessed using the Newcastle-Ottawa Scale (NOS). The primary outcome was an estimate of the risk of dementia in elderly hypertensive CCBs users. The pooled relative risk (RR) was calculated using a generic inverse variance method. A subgroup analysis was also performed based on CCB class. Statistical analyses were performed using Review Manager Version 5.3. The meta-analysis included ten studies comprising 75,239 patients (53.16% female) with a median age and follow-up duration of 72.24 years and 8.21 years respectively. All of the studies were of high quality. The use of CCBs was associated with a significant reduction in the risk of developing dementia in elderly hypertensive patients (RR 0.70 [95% CI: 0.58-0.85] p = 0.0003) compared to those not using CCBs. In subgroup analysis we found that the dihydropyridine class was associated with a 44% [RR 0.56 (95% CI: 0.40-0.78) p = 0.0005] reduction in the dementia risk. The use of CCBs was associated with a significant reduction in the risk of developing dementia in elderly hypertensive patients.