Heart rate recovery and risk of cardiovascular events and all-cause mortality: A meta-analysis of prospective cohort studies

Background-heart rate recovery (hrr) is a noninvasive assessment of autonomic dysfunction and has been implicated with risk of cardiovascular events and all-cause mortality. however,evidence has not been systematically assessed. we performed a metaanalysis of prospective cohort studies to quantify these associations in the general population. methods and results-a literature search using 3 databases up to august 2016 was conducted for studies that reported hazard ratios with 95% cis for the association between baseline hrr and outcomes of interest. the overall hazard ratios were calculated using a random-effects model. there were 9 eligible studies in total,with 5 for cardiovascular events enrolling 1061 cases from 34 267 participants,and 9 for all-cause mortality enrolling 2082 cases from 41 600 participants. the pooled hazard ratios associated with attenuated hrr versus fast hrr that served as the referent were 1.69 (95% ci 1.05-2.71) for cardiovascular events and 1.68 (95% ci 1.51-1.88) for all-cause mortality. for every 10 beats per minute decrements in hrr,the hazard ratios were 1.13 (95% ci 1.05-1.21) and 1.09 (95% ci 1.01-1.19),respectively. further analyses suggested that the associations observed between attenuated hrr and risk of fatal cardiovascular events and all-cause mortality were independent of traditional metabolic factors for cardiovascular disease (all p < 0.05). conclusions-attenuated hrr is associated with increased risk of cardiovascular events and all-cause mortality,which supports the recommendation of recording hrr for risk assessment in clinical practice as a routine. © 2017 the authors.