Longitudinal association between accelerometer-derived rest-activity rhythm and atherosclerotic cardiovascular disease

Objective: Rest-activity rhythm is an essential behavior for human health. However, the association between restactivity rhythm and atherosclerotic cardiovascular disease (ASCVD) risk remains unclear. Therefore, this study aimed to elucidate the association. Methods: This study included 87,039 participants from the UK Biobank who had 7-day accelerometry data and were free of ASCVD at baseline. Relative amplitude was calculated as the difference between the most active continuous 10-h period (M10) and the least active continuous 5-h period (L5) in 24 h, and lower relative amplitude indicated the disruption of rest-activity rhythm. Cox proportional hazard model was used to examine the association of relative amplitude with ASCVD. Further, the linear association between relative amplitude and arterial stiffness measurements, including arterial stiffness index (ASI) and carotid intima-media thickness (cIMT), was examined. Results: During a mean follow-up period of 6.80 +/- 1.10 years, 2798 ASCVD cases were identified. A doseresponse relationship was observed between relative amplitude and ASCVD risk (P for trend<0.001). The adjusted hazard ratio, for the highest vs the lowest quintile of relative amplitude, was 1.54 (95 % confidence interval: 1.31, 1.79). Further, we found significant association of lower relative amplitude with ASI and cIMT. The onset timing of M10 at <= 06:00, 09:00, 10:00, or >= 11:00, as opposed to the reference time of 07:00, was associated with higher ASCVD risk. Conclusions: Low rest-activity rhythm amplitude was associated with a higher risk of ASCVD. Rest-activity rhythm amplitude may provide a method to identify individuals at risk of ASCVD in public health and clinical practice.