Heart Rate and Heart Rate Variability Changes Are Not Related to Future Cardiovascular Disease and Death in People With and Without Dysglycemia: A Downfall of Risk Markers? The Whitehall II Cohort Study

<b>Objective</b> <p>Higher resting heart rate (rHR) and lower heart rate variability (HRV) are associated with increased risk of cardiovascular disease (CVD) and all-cause mortality in people with and without diabetes It is unknown whether temporal changes in rHR and HRV may contribute to this risk. We investigated associations between 5-year changes in rHR and HRV and risk of future CVD and death, taking into account participants’ baseline glycemic state. </p> <p><b>Research design and Methods</b></p> <p>In this prospective population-based cohort study we investigated 4,611 CVD-free civil servants (mean age 60, SD=5.9 years, 70% men).<b> </b>rHR and/or 6 indices of HRV were measured. Associations of 5-year change in 5-minute rHR and HRV with fatal- and non-fatal CVD and all-cause mortality or the composite of the two were assessed with adjustments for relevant confounders. Effect modification by glycemic state was tested. </p> <p><b>Results</b></p> <p>At baseline, 63% of participants were normoglycemic, 29% had prediabetes and 8% had diabetes. During a median (IQR) follow-up of 11.9 (11.4;12.3) years, 298 participants (6.5%) experienced a CVD event and 279 (6.1%) died from non-CVD related causes. We found no association between 5-year changes in rHR and HRV and future events. Only baseline rHR was associated with all-cause mortality. A 10 beats per minute higher baseline level showed a 11.4% higher rate of all-cause mortality (95%CI:1.0;22.9%, P=0.032). Glycemic state did not modify associations<b>. </b></p> <p><b>Conclusion</b></p> <p>Changes in rHR and HRV and possibly also baseline values of these measures are not associated with future CVD or mortality in people with or without dysglycemia. </p>