Objective:
to investigate the associations between irregular and late sleep–wake cycle and cardiovascular risk factors.
Design and method:
Activity rhythms for 5–7 days were measured objectively using the actigraph Actilife GT3X + in 89 participants of the Saint-Petersburg population-based sample (from the epidemiological study ESSE-RF). All subjects underwent a structured interview (lifestyle, medical history, sleep characteristics), anthropometric measurements and office blood pressure evaluation. The blood tests included lipid profile, glucose, creatinine, uric acid, insulin, CRB, leptin, adiponectin, cortisol. Based on actigraphy data we analyzed physical activity, sleep parameters (sleep onset later than midnight was considered as late) and nonparametric indicators (‘nparACT’ package for R) with calculation of the interdaily stability (IS) and intradaily variability (IV) of sleep-wake cycle.
Results:
Altogether 54 subjects completed at least 5 days of actigraphy. IS negatively correlated with lipoprotein (a) (– 0,34, p = 0,002), leptin (−0,26, p = 0,05) and hips circumference (−0,26, p = 0,012). IV negatively correlated with Tg (−0,24, p = 0,03) and energy expenditure in kcal (−0,23, p = 0,04). Subjects with late sleep onset burn less kcals (p = 0,03), have higher greater waist (p = 0,007) and hips (p = 0,04) circumferences, and higher systolic blood pressure (p = 0,026).
Conclusions:
irregular and late sleep for cardiovascular diseases are associated with lipoprotein (a), leptin, waist and hips circumferences and systolic blood pressure which might have an impact on cardiovascular risk (Grant LSSR #075-02-2018-57, 16.11.2018).
