A 10-year follow-up study of the association between calcium channel blocker use and the risk of dementia in elderly hypertensive patients

Calcium channel blockers (CCBs) are widely used for reducing blood pressure of hypertensive patients. Recent reports document the beneficial effects of CCB for preventing dementia; however, the results are controversial. We aim to evaluate the risk of developing dementia among elderly hypertensive patients treated with CCB. We designed a retrospective population-based cohort study using the records of the National Health Insurance Research Database of Taiwan dated from 2000 to 2010. The study cohort comprised 82,107 hypertensive patients of more than 60 years of age, and 4004 propensity score (PS)-matched pairs were selected according to age, sex, year of hypertension diagnosis, and baseline comorbidities. We employed a robust Cox proportional hazard model to estimate the hazard ratio (HR) of developing dementia in the PS-matched cohort. The annual incidence of dementia in the CCB-exposure group was significantly lower than that in the comparator group (3.9 vs 6.9 per 1000 person-years, P < 0.01) during the follow-up period (4.4 +/- 2.5 years). Based on the PS-matched cohort, the adjusted HR of dementia in the CCB-exposure group was significantly lower than that in comparator group (HR = 0.53, 95% confidence interval: 0.39-0.72, P < 0.01). Sensitivity and subgroup analyses also confirmed similar findings. Our results provided evidence for an association between CCB use and a lower risk of developing dementia among the elderly hypertensive patients. Further studies are required to explore the causal relationship between CCB use and dementia.