A cross-sectional study of sleep and depression in a rheumatoid arthritis population

Objectives To assess the prevalence of impaired sleep quality and depression in a rheumatoid arthritis population and determine their correlation with Disease Activity Score (DAS) and its components. Methods In this single-centre observational cross-sectional study, data was collected by the assessing clinician for DAS28, age and gender in various treatment groups according to use of csDMARDs, biologics and long-term steroids. Presence of impaired sleep quality and depression was assessed by the Pittsburgh Sleep Quality Index (PSQI) and Public Health Questionnaire 9 (PHQ 9). Correlation for DAS and its components with the outcomes was determined by Pearson’s correlation coefficient. Multivariate analysis was performed by logistic regression. Results Two hundred patients were included. The prevalence across all subgroups of poor sleep quality and depression were 86.5% and 30%, respectively, with a correlation coefficient of 0.69 between the two and poor sleep quality amongst all RA patients with comorbid depression. Multivariate analysis found only subjective DAS components, tender joint count (TJC) and patient global health visual analogue score (VAS) to significantly correlate with both outcomes. Age inversely correlated with depression. Long-term steroid use was associated with poorer sleep quality, but there was no significant effect of csDMARDs or biologics. There was no significant difference in prevalence of depression amongst treatment subgroups. Conclusion Poor sleep quality and to a lesser extent depression are prevalent in the general rheumatoid arthritis population. Patients would benefit from clinicians measuring these outcomes routinely as they constitute a significant non-inflammatory burden of living with rheumatoid disease. Key Points • Subjective components of DAS independently correlate with sleep quality and depression, while objective components do not. • Poor sleep quality is highly prevalent in RA and present in all those with comorbid depression. • Poor sleep quality and depression incidence in RA are much lower when DAS is low or remission.