Long Sleep Duration is Associated with Increased High-Sensitivity C-Reactive Protein: A Nationwide Study on Chinese Population

Abstract

Purpose

High-sensitivity C-reactive protein (hs-CRP) has been shown as an important predictor of cardiovascular risk, and sleep duration is an important factor influencing health outcomes. However, the association between hs-CRP and sleep duration among Chinese adults remained unknown and controversial. We aimed to explore the associations between sleep duration and hs-CRP levels among Chinese adults, and the differences in sex and geographical regions.

Methods

This cross-sectional study was based on nationally representative Chinese samples from the 2009 China Health and Nutrition Survey, which employed multistage, random cluster designs. Habitual sleep duration was self-reported with short and long sleep duration defined as ≤6h and ≥9h per day, respectively. Participants were divided into 4 groups based on the categories of self-reported sleep duration (≤6h, 7h, 8h, ≥9h per day), excluding hs-CRP levels ≥10 mg/L. Subset samples were stratified by sex and geographical regions.

Results

A total of 8170 Chinese adults with a mean age of 50.0±14.9 years and 4369 (53.5%) men were included. Participants sleeping eight hours had the lowest hs-CRP levels. Long sleep duration (≥9h) was significantly associated with elevated hs-CRP levels after adjusting for multiple covariates in full samples (β=0.0356; 95% CI: 0.0050–0.0663; P=0.0228), but the associations of short sleep duration (≤ 6h) were limited to the unadjusted model. Long sleep duration was associated with elevated hs-CRP levels in women (β= 0.0512; 95% CI: 0.0097–0.0927; P=0.0155) and in the northern region of China (β=0.0699; 95% CI: 0.0210–0.1187; P=0.0051), but not in men or the southern region.

Conclusion

Long but not short sleep duration was positively associated with elevated hs-CRP levels, independent from traditional risk factors among Chinese adults, and sex and geographical differences were observed. Our findings imply that modifications of long sleep duration might be added to behavioral therapy to reduce cardiovascular risk in Chinese adults.

Keywords:

• high-sensitivity C-reactive protein
• sleep duration
• cardiovascular risk
• Chinese population

Abbreviations

BMI, body mass index; CHNS, China Health and Nutrition Survey; CRP, C-reactive protein; CVD, cardiovascular disease; DBP, diastolic blood pressure; HDL-C, high density lipoprotein cholesterol; hs-CRP, high-sensitivity C-reactive protein; LDL-C, low density lipoprotein cholesterol; MI, myocardial infarction; SBP, systolic blood pressure; TG, triglycerides; UA, uric acid.

Data Sharing Statement

The datasets generated and/or analyzed during the current study are available in the CHNS repository, http://www.cpc.unc.edu/projects/china.

Ethics Approval

The China Health and Nutrition Survey (CHNS) is an ongoing open cohort, international collaborative project between the Carolina Population Center at the University of North Carolina at Chapel Hill and the National Institute for Nutrition and Health.²⁴ The study was approved by the institutional review boards of the University of North Carolina at Chapel Hill and the National Institute for Nutrition and Health as well as the Chinese Center for Disease Control and Prevention.

Acknowledgments

All authors are grateful to the National Institute of Nutrition and Food Safety, China Center for Disease Control and Prevention, Carolina Population Center, The University of North Carolina at Chapel Hill and the Fogarty International Center for providing the data use. We also thank the China-Japan Friendship Hospital and the Ministry of Health for support for the CHNS 2009 survey. The authors are also grateful to the Staff of the Peking Union Medical College Hospital and all who actively participated in the study.

Author Contributions

Study concept and design: Zhang, He and Yang. Search of the relevant database and Quality assessment of each study: He, Yang and Zhang. Data extraction and confirmation of statistical analysis: He, Yang and Zhang. Statistical analysis: He, Zhang. Examination for the methodology: He and Zhang. Drafting of the manuscript: He and Zhang. Critical revision of the manuscript for important intellectual content: He, Yang, Xu, Ping, Wei Li, Zhang and Yuxiu Li. Obtained funding: Zhang. Administrative, technical, and material support: Zhang. Study supervision: Zhang. All authors have approved the final article. All authors made substantial contributions to conception and design, acquisition of data, or analysis and interpretation of data; took part in drafting the article or revising it critically for important intellectual content; agreed to submit to the current journal; gave final approval of the version to be published; and agree to be accountable for all aspects of the work.

Disclosure

The authors declare that they have no competing interests.

Additional information

Funding

The work was supported in part by the National Natural Science Foundation of China (91846106), Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences Clinical, and translational medicine research fund (2019XK320029). The Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences (CIFMS2016-I2M-4-001), Training Program for Excellent Talents in Dongcheng District, and the Education Reforming Program, Peking Union Medical College (No. 2018zlgc0119) also funded the research. These organizations had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; or the decision to submit the manuscript for publication.