Prevalence of psoriatic arthritis and its correlates among patients with psoriasis in Greece: results from a large retrospective study

Objectives: To evaluate the prevalence and its clinical characteristics of psoriatic arthritis (PsA) in a specialized psoriasis clinic of a University Hospital.

Methods: In this retrospective study, 278 patients with psoriasis were evaluated between 2011 and 2013.

Results: The study included 278 patients with psoriasis: 144 (52%) were male and 134 (48%) female. Their median age was 51.41 with median psoriasis presenting age of 34.52 years. Referring to the type of psoriasis, 86% presented with plaque psoriasis, 5% guttate, 2% palms and soles, 2% inverse, 1% pustular and 4% with psoriasis of more than one type. Nail disease appeared in 121 patients (43.5%) and scalp disease in 175 (63%). Of these patients, 85 (30%) had PsA, whereas 51% of patients with PsA had psoriatic nail disease. With reference to the PsA type, 43 (51%) patients presented with polyarthritis, 10 (12%) with oligoarthritis, 7 (8%) with axial arthritis, whereas the rest 25 of them (31%) had PsA of more than one type. The subgroup of patients with PsA had significantly higher rates of comorbidities including arterial hypertension, diabetes and hypercholesterolaemia compared to non-PsA patients with 41% vs. 17% (P = 0.001), 20% vs. 8% (P = 0.021) and 41% vs. 19% (P = 0.004), respectively.

Conclusion: The prevalence of PsA among patients with psoriasis was relatively higher in Greece compared to other ethnic-based studies. Comorbidities related to life expectancy were more frequent. As there is a high percentage of undiagnosed cases with active arthritis among patients with psoriasis, dermatologists should be aware of PsA clinical signs in order to recognize it earlier and provide successful treatment.