The associations between sleep timing and night sleep duration with dyslipidemia in a rural population: The Henan Rural Cohort Study

ABSTRACTEvidence linking sleep timing and night sleep duration to dyslipidemia was limited and inconclusive, especially among low- and middle-income adults. The aims were to evaluate the associations between sleep timing, night sleep duration and dyslipidemia in a rural population. Based on the Henan Rural Cohort Study, a total of 37 164 participants were included. The Pittsburgh Sleep Quality Index was used to collect sleep information. Logistic regression and restrictive cubic splines were conducted to explore the associations. Of the 37 164 enrolled participants, 13881 suffered from dyslipidemia. Compared to the reference groups, people who went to sleep after 23:00 or woke up after 7:30 had higher prevalence of dyslipidemia, the adjusted odds ratios (ORs) and 95% confidence intervals (CIs)were 1.30 (1.20–1.41) and 1.34 (1.19–1.50). The adjusted OR (95%CI) of participants in the Late-sleep/Late-rise category compared to the Early-sleep/Early-rise category was 1.55 (1.08–1.23). Compared to the reference (7~≤8 h), the adjusted OR (95%CI) was 1.11 (1.03–1.20) for longer (>9 h) night sleep duration. Moreover, the combined effects of sleep duration (>9 h) with sleep time (22:00~) (OR = 1.46, 95%CI: 1.16–1.84), sleep duration (>9 h) with wake-up time (≥7:30) (OR = 1.28, 95%CI: 1.08–1.51), and sleep duration (>9 h) with the Late-sleep/Late-rise category (OR = 1.41, 95%CI: 1.14–1.75) increased the prevalence of dyslipidemia. Accordingly, our results indicate that delayed sleep timing and longer night sleep duration had independent and joint effects on higher risks of dyslipidemia in rural population.KEYWORDS: Sleep timingsleep timewake-up timenight sleep durationdyslipidemiarural population AcknowledgmentsThe authors thank all the participants, coordinators, and administrators for their support and help during the research.Author contributionCW and PD conceived and designed the study. RZ, JY, ZZ, HZ, FJ, CS, XL, and JH coordinated data collection. RZ, JY, ZZ conducted the analyses. RZ wrote the manuscript. All authors have contributed to the revision of the manuscript and approved the final manuscript for publication.Disclosure statementNo potential conflict of interest was reported by the author(s).Data availability statementThe datasets generated and/or analyzed during the current study are available from the corresponding author on reasonable request.Supplementary dataSupplemental data for this article can be accessed online at https://doi.org/10.1080/07420528.2023.2262565.Additional informationFundingThis research was supported by the Foundation of National Key Program of Research and Development of China [Grant NO: 2016YFC0900803], National Natural Science Foundation of China [Grant NO: 81573243, 81602925], Discipline Key Research and Development Program of Zhengzhou University [Grant NO: XKZDQY202008, XKZDQY202002]. The funders had no role in the study design, data collection, and analysis, decision to publish, or preparation of the manuscript.