Effects and differences of sleep duration on the risk of new-onset chronic disease conditions in middle-aged and elderly populations

Abstract

Background: Few longitude cohort studies investigated the risk of the duration of nighttime sleep and naps to the new-onset common chronic disease conditions (CDCs) in middle-aged (45-60) and the elderly (age ≥ 60) populations using an age-stratified strategy.

Methods: The 7025 participants from The China Health and Retirement Longitudinal Study were screened as eligible subjects. Established 13 cohorts with CDCs, acquired their' sleep records in 2011, and obtained new-onset incidents of CDCs during follow-up in 2011-2018. Performed risk association analyses between sleep duration and 13 new-onset CDCs respectively.

Results: New-onset risk of four CDCs decreased with increasing nighttime sleep (p-nonlinear>0.05). The risk threshold was approximately 7 hours in middle-aged people and 6 hours in the elderly. For the middle-aged population, compared with 7-9hours sleep, <5hour and 5-7hours nighttime sleep were associated with 1.312∼1.675 times more risk of hypertension, kidney disease, diabetes or high blood sugar status, and multimorbidity; Compared with no nap, a 0-30 min nap was associated with 1.413(1.087∼1.837) times the heart disease risk. In the elderly, < 5 hours of night sleep was a significant risk factor for four CDCs including kidney disease and multimorbidity, etc. A long night's sleep (>9 hours) was connected with 61.2% reduction in risk of memory disease, a >90 min nap increased 62% risk of memory disease, and a 0-30 min nap was associated with higher risks of heart disease, hypertension, and a lower kidney disease risk.

Conclusions: Nighttime sleep and daytime naps may have their own implications for the new-onset CDCs' risk in the aging process.

Keywords: Chronic diseases; Middle-aged and elderly; Nap; Night sleep; Sleep duration; The China Health and Retirement Longitudinal Study (CHARLS).