Clinical profile, treatment and quality of life of patients with psoriatic arthritis in Malaysia: A population-based cross-sectional study

Psoriatic arthritis (PsA) is a major comorbidity of psoriasis and may lead to irreversible joint damage and disability. This study aims to describe the clinical profile, treatment and quality of life (QoL) of patients with PsA in Malaysia. This is a multicentre retrospective cross-sectional study of psoriasis patients who were notified to the Malaysian Psoriasis Registry (MPR) from January 2007 to December 2018. Of 21 735 psoriasis patients, 2756 (12.7%) had PsA. The male to female ratio was 1:1. The mean age of psoriasis onset for PsA patients was 34.73 +/- 14.44 years. They had a higher rate of family history of psoriasis (26% vs. 22.4%, p < 0.001), scalp (82.7% vs. 81.0%, p = 0.04) and nail involvement (73.3% vs. 53.3%, p < 0.001), obesity (62.6% vs. 54.4%, p < 0.001), dyslipidaemia (23.8% vs. 15.4%, p < 0.001), hypertension (31.1% vs. 22.7%, p < 0.001) and diabetes mellitus (20.9% vs. 15.2%, p < 0.001) compared to non-PsA patients. More than half (54.3%) had severe psoriasis [(body surface area >10% and/or Dermatology Life Quality Index (DLQI) >10)]. Most had oligo-/monoarthropathy (40.3%), followed by distal interphalangeal arthropathy (31.3%), symmetrical polyarthropathy (28.3%), spondylitis/sacroiliitis (8.2%) and arthritis mutilans (3.2%). Nearly 40% of PsA patients received systemic treatment, but only 1.6% received biologic agents. QoL was more significantly affected in PsA than in non-PsA patients (mean DLQI 10.12 +/- 7.16 vs. 9.52 +/- 6.67, p < 0.001). One in eight patients with psoriasis in Malaysia had PsA. They had a higher incidence of comorbidities, severe disease, impaired QoL and were more likely to receive systemic and biological treatment compared to non PsA patients.