Association of accelerometer-measured rest-activity rhythm patterns and parameters with cardiovascular and all-cause...

Rest-activity rhythm (RAR) is a fundamental biomarker of age-related circadian system deterioration. However, the long-term effect of RAR patterns on mortality in older adults remains unclear.

This study analysed data from National Health and Nutrition Examination Survey 2011-2014. The RAR parameters were derived from wrist accelerometers, and four patterns were identified through clustering analysis using Gaussian mixture models. Cox models were used to compare the hazard ratio (HR) and 95% confidence interval (CI) of mortality among participants with different RAR parameters and patterns.

This study included 1710 participants aged ≥60 years. The median follow-up duration was 6.67 years. In total, 269 all-cause deaths and 77 cardiovascular deaths occurred during follow-up period. Four RAR patterns were identified: 'morning-type', 'earlier-type', 'delayed-type', and 'evening-type'. Compared to 'morning-type', 'evening-type' was associated with higher risks of cardiovascular (HR: 12.16, 95% CI: 4.02-36.82) and all-cause mortality (HR: 3.31, 95% CI: 1.91-5.72). Higher interdaily stability was associated with lower risks of cardiovascular (HR: 0.67, 95% CI: 0.55-0.81), and all-cause mortality (HR: 0.86, 95% CI: 0.74-1.00). Higher relative amplitude was associated with lower risks of cardiovascular (HR: 0.61, 95% CI: 0.49-0.75), and all-cause mortality (HR: 0.70, 95% CI: 0.60-0.81). Conversely, higher intradaily variability was associated with increased risk of cardiovascular (HR: 1.30, 95% CI: 1.15-1.46) and all-cause mortality (HR: 1.19, 95% CI: 1.10-1.30).

RAR patterns and parameters were significantly associated with cardiovascular and all-cause mortality in older adults. Early identification and intervention for adverse RAR patterns may help improve long-term health outcomes.