Sleep disturbances are more common in patients with psoriatic arthritis (PsA) compared with patients with psoriasis and healthy control participants, and are associated with inflammatory and noninflammatory disease measures, according to results of a study published in Scandinavian Journal of Rheumatology.
Researchers examined the prevalence of sleep disturbances, assessed associations between poor-quality sleep and clinical and patient-reported outcomes, and evaluated the effect of PsA treatment on the quality of sleep.
The cross-sectional study (ClinicalTrials.gov Identifier: NCT02572700) included patients from the Parker Institute’s PsA patient cohort who were initiating or switching treatment. Patients with psoriasis and healthy control participants were enrolled in the comparison groups. The Pittsburgh Sleep Quality Index (PSQI) was determined from patient questionnaires, with other patient data collected from patient clinical records.
The researchers evaluated associations between PSQI scores and disease outcome measures using univariate and multivariate regression analyses. A subset of patients with PsA who initiated treatment were assessed after 4 months to determine the effects of medical treatment on sleep quality. The PSQI scores were analyzed over time using a mixed-effect model.
A total of 109 patients with PsA, 20 patients with psoriasis, and 20 healthy control participants were included in the study. Poor-quality sleep was reported by 66.1% (n=72) of patients with PsA, 45% (n=9) of patients with psoriasis, and 15% (n=3) of healthy control participants.
Statistically significant associations (P <.001) were found between PSQI and Disease Activity Score-28 with C- reactive protein (DAS28CRP), tender points, visual analog scale (VAS) patient global and pain, PsA Impact of Disease (PsAID) fatigue, Health Assessment Questionnaire (HAQ), and painDETECT score.
In multivariate regression analyses, VAS patient global, VAS pain, and tender joints were independently associated with PSQI.
Among patients with PsA, 57 of the 109 were included in the follow-up to assess the effect of treatment on quality of sleep, as measured by PSQI scores. However, researchers noted a lack of a statistically significant effect of PsA treatment on PSQI over time.
Limitations of the study included the lack of a Danish version of the PSQI questionnaire, the small number of patients with follow-up PSQI data after initiating treatment, the potential for chronic pain to affect the performance of the painDETECT score, and the use of tender points as a proxy for fibromyalgia.
Researchers concluded, “Additional investigation of underlying mechanisms causing sleep disturbance in PsA is needed to understand the multifactorial origins that may provide important information on how to manage sleep disturbance in this patient group.”
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Skougaard M, Stisen ZR, Jørgensen TS, et al. Increased prevalence of sleep disturbance in psoriatic arthritis is associated with inflammatory and non-inflammatory measures. Scand J Rheumatol. Published online March 18, 2022. doi:10.1080/03009742.2022.2044116