Determinants of sleep impairment in psoriatic arthritis: An observational study with 396 patients from 14 countries

Objective: Sleep quality is diminished in patients with psoriatic arthritis (PsA) and close to 40% of PsA patients consider sleep difficulties a priority domain. This work analyzes determinants of impaired sleep in patients with PsA. Methods: This was a cross-sectional analysis of an observational study (ReFlap, NCT NCT03119805), which included adult patients with definite PsA with >= 2 years disease duration from 14 countries. Sleep was assessed using the patient self-reported evaluation of sleep on a 0-10 numerical scale, included in the Psoriatic Arthritis Impact of Disease questionnaire (PSAID-12). A score >= 4 was considered as sleep impairment. Demographic and clinical variables associated to sleep impairment were assessed through univariate analysis and Poisson regression modeling leading to prevalence ratio (PR) [95% confidence interval]. Results: A total of 396 patients were analyzed: mean age 51.9 +/- 12.6 years, 51% were females, 59.7% were receiving biologic therapy, 53.3% had 1-5% of body surface area affected by psoriasis; 23.7% were in remission and 36.9% in low disease activity according to the Disease Activity in Psoriatic Arthritis (DAPSA) score. Median (25th-75th) patient's self-evaluation of sleep difficulties was 2 (0-6), 157 (39.6%) had sleep impairment. In the Poisson regression model, self-reported levels of anxiety (PR: 1.05 [1.02-1.08], A= 0.003) and pain (PR: 1.06 [1.04-1.09], P< 0.001) were independently associated to sleep impairment. Conclusions: In this multicentric study, sleep impairment was present in 40% of PsA patients; pain and anxiety were associated to sleep impairment whereas inflammation was not. Impact on sleep appears multifactorial in PsA. (C) 2020 Societe francaise de rhumatologie. Published by Elsevier Masson SAS. All rights reserved.