Temporal Changes in Resting Heart Rate and Risk of Diabetes Mellitus.

Backgruound: To investigate the association between the time-varying resting heart rate (RHR) and change in RHR (∆RHR) over time and the risk of diabetes mellitus (DM) by sex.
Methods: We assessed 8,392 participants without DM or atrial fibrillation/flutter from the Korean Genome and Epidemiology Study, a community-based prospective cohort study that was initiated in 2001 to 2002. The participants were followed up until December 31, 2018. Updating RHR with biennial in-study re-examinations, the time-varying ∆RHR was calculated by assessing the ∆RHR at the next follow-up visit.
Results: Over a median follow-up of 12.3 years, 1,345 participants (16.2%) had DM. As compared with RHR of 60 to 69 bpm, for RHR of ≥80 bpm, the incidence of DM was significantly increased for both male and female. A drop of ≥5 bpm in ∆RHR when compared with the stable ∆RHR group (-5< ∆RHR <5 bpm) was associated significantly with lower risk of DM in both male and female. However, an increase of ≥5 bpm in ∆RHR was significantly associated with higher risk of DM only in female, not in male (hazard ratio for male, 1.057 [95% confidence interval, 0.869 to 1.285]; and for female, 1.218 [95% confidence interval, 1.008 to 1.471]).
Conclusion: In this community-based longitudinal cohort study, a reduction in ∆RHR was associated with a decreased risk of DM, while an increase in ∆RHR was associated with an increased risk of DM only in female.