Weekend Sleep Extension, Social Jetlag and Incidence of Coronary Calcium Score: the ELSA-Brasil study

Insufficient/irregular sleep patterns are common conditions, but their cardiovascular consequences and strategies to minimize these risks are poorly explored. We aimed to determine whether weekend sleep extension (catch-up sleep) and social jetlag may impact the incidence of subclinical atherosclerosis. We performed a 7-day wrist actigraphy in this cohort study to monitor sleep parameters. Coronary artery calcium (CAC) was measured at two different time points. Catch-up-sleep was measured by calculating weekend minus weekday sleep duration. Social jetlag was calculated by the difference between the mean sleep midpoint on weekend days minus weekdays. The incidence of subclinical atherosclerosis was defined as baseline CAC=0, followed by CAC>0 at the follow-up. The association of incident CAC outcome was assessed using logistic regression adjusting for traditional confounders plus sleep apnea. We analyzed 1,832 participants (age: 48.8±8.0 years; 57.8% women). Incidence of CAC among subjects with catch-up sleep >90 and ≤90 minutes were 19.1% vs. 31.7%, respectively (P<0.001). In covariate-adjusted analyses (follow-up=5.4±0.90 years), we found a lower incidence of CAC in those participants with catch-up-sleep >90 minutes (OR=0.62; 95% CI 0.52-0.74). Interestingly, stratified analysis revealed that these results are modified by sleep duration (≤6.55 hours: OR=0.42; 95% CI 0.33-0.54; >6.55 hours: OR=0.96; 95% CI 0.75-1.24). In contrast, social jet lag was weakly associated with incident CAC: 0.1% increasing risk/minute. Extending sleep time during the weekend is independently associated with lower 5-year CAC incidence, providing relevant insights into the cardiovascular benefits of this common sleep habit Worldwide.