Sleep quality in patients with psoriatic arthritis

The purpose of this study was to determine the effects of psoriatic arthritis (PsA) on sleep quality and investigate the association between sleep quality and clinical parameters of PsA, quality of life and psychological state in patients with PsA.

Forty-one patients with PsA and 38 healthy volunteers were included in this study. In both patients and healthy controls, sleep quality was assessed by means of the Pittsburgh Sleep Quality Index (PSQI) and anxiety and depression were assessed by means of the Hospital Anxiety and Depression Scale (HADS). In addition, PsA Quality of Life (PsAQoL) Index and Psoriasis Area and Severity Index (PASI) were used on patients. Generalized pain was assessed by means of a visual analogue scale (VAS).

Subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbance, daytime dysfunction and total PSQI scores were significantly higher in patients with PsA compared to healthy controls. Total PSQI scores significantly correlated with anxiety, generalized pain, PsAQoL scores, enthesitis and levels of C-reactive protein (CPR) and erythrocyte sedimentation rate (ESR) (P < 0.05). Also, multiple regression analysis indicated that ESR level was independently associated with total PSQI score (P < 0.05, R²  = 0.325).

Sleep quality is diminished in patients with PsA. Sleep disturbance is particularly associated with generalized pain, anxiety, enthesitis and levels of CRP and ESR in patients carrying the diagnosis of PsA.