Dose-response Relationship between Sleep and Rheumatoid Arthritis.

Objectives: In this study, we explored the association between sleep quality, duration and prevalence of rheumatoid arthritis (RA) among low-income adults in rural areas of China. Methods: Face-to-face investigation were conducted in 2017, and completed questionnaires were obtained from 16,648 individuals. Sleep quality and duration were evaluated using the standard Pittsburgh Sleep Quality Index. RA was based on self-reported physician diagnosis. Logistic regression analysis and restricted cubic spline models were performed. Results: Sleep duration shorter than 7 hours was associated with increased odds of RA, with an odds ratio (OR) of 1.49 for 6–<7 hours and 1.70 for <6 hours. Poor sleep quality was associated with RA, with an OR of 1.68. The combination category of poor sleep quality and any group of sleep duration was associated with a significantly increased risk of developing RA. Combined groups of good sleep quality with short sleep duration (<7 hours) were also found to be related to prevalence of RA. There was a non-linear relationship between sleep quality, duration and the odds of RA. Conclusions: Poor sleep quality and short sleep duration may be trigger or risk factors for RA. [ABSTRACT FROM AUTHOR]