Prevalence and variables associated with fatigue in psoriatic arthritis: a cross-sectional study

To describe the prevalence of and evaluate the factors associated with fatigue patients with psoriatic arthritis (PsA) in an Asian population.

We used baseline data from a registry of patients with PsA attending an outpatient clinic of a tertiary hospital in Singapore. Demographic data and disease characteristics were evaluated. Fatigue was assessed by question one of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI-F) and the vitality domain of the Medical Outcome Survey, Short-Form 36 (SF-36 VT). We evaluated clusters of variables, and individual variables in association with fatigue.

We included 131 patients (50.4% men, 63.4% Chinese, median PsA duration 21.0 months) with completed data for fatigue. Forty-five patients (34%) experienced severe fatigue (defined by BASDAI-F > 5/10). We used principal component analysis and identified five clusters of variables that explained 62.9% of the variance of all factors. Of these, disease activity and impact, and disease chronicity were significantly associated with BASDAI-F and SF-36 VT. In multivariable analyses, back pain, peripheral joint pain and patient global assessment were associated with BASDAI-F, whereas peripheral joint pain and mental health were associated with SF-36 VT.

PsA-associated fatigue is prevalent in this Asian PsA cohort and is associated with disease activity, impact and chronicity.