Association between sleep disorders and rheumatoid arthritis in U.S. adults.

BACKGROUND

Evidence on the association between sleep disorders and rheumatoid arthritis (RA) remains limited. This study aimed to investigate this relationship in U.S. adults using data from the National Health and Nutrition Examination Survey (NHANES).

METHODS

This cross-sectional study included adults aged ≥ 18 years from the 2005-2018 NHANES cycles. A total of 28,040 participants were included. Weighted multivariate logistic regression models were employed to assess the association between sleep disorders and RA. Three models were constructed: an unadjusted model, a minimally adjusted model controlling for demographic variables, and a fully adjusted model incorporating additional lifestyle and clinical covariates. Subgroup analyses were performed to assess the consistency of associations across different population strata, and sensitivity analyses were conducted to confirm the robustness of the results.

RESULTS

Of the 28,040 participants, 4168 (14.32%) were identified as having sleep disorders, and 1589 (4.28%) reported having RA. In the fully adjusted model, sleep disorders were significantly associated with increased odds of RA (OR = 1.76, 95% CI: 1.46-2.13, P < 0.001). Subgroup analyses showed that this positive association persisted across all examined strata, with no significant interactions (P for interaction > 0.05).

CONCLUSIONS

In conclusion, our findings indicate a statistically significant association between sleep disorders and the prevalence of RA in U.S. adults. However, given the limitations of the cross-sectional design, causal inferences cannot be made. Future longitudinal and mechanistic studies are warranted to clarify the temporal direction and biological pathways underlying this association.