Resting Heart Rate and Cognitive Decline: A Meta-Analysis of Prospective Cohort Studies.

BACKGROUND AND PURPOSE: Several previous meta-analyses have identified an association between cognitive decline and heart rate variability, which reflects autonomic nerve activity. This systematic review and meta-analysis investigated the impact of increased resting heart rate (RHR) on the incidence of cognitive decline, including dementia. METHODS: The PubMed, Embase, and PsycInfo databases were searched for relevant prospective cohort studies published before April 18, 2022. A methodological quality assessment of the included studies was conducted using the Newcastle-Ottawa Scale. Summary estimates of the incidence of cognitive decline, including dementia, were generated using a random-effects model. Potential publication bias was evaluated using Begg's funnel plots and Egger's regression tests. RESULTS: The meta-analysis included 7 prospective cohort studies comprising 53,621 participants. A weak significant association was observed between RHR and the risk of cognitive decline, although the analysis indicated high heterogeneity among the studies (relative risk=1.18, 95% confidence interval=1.04-1.33, I²=82.5%). Significant associations were determined between RHR and all combined types of dementia except for Alzheimer's disease and mild cognitive impairment. There was also a dose-response association between increased RHR and cognitive decline. The meta-estimate of the cognitive decline risk associated with a 10 beat-per-minute increase in RHR was 1.06, and it was 1.10 for dementia. CONCLUSIONS: This study found that a higher RHR was associated with an increased cognitive decline risk. Due to study limitations such as publication bias and high heterogeneity, additional studies are required to validate this finding. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration number CRD42021282912.