Characteristic and Outcome of Psoriatic Arthritis Patients with Hyperuricemia

To determine the characteristics of patients with psoriatic arthritis (PsA) who have hyperuricemia (HUC) and their outcomes, especially cardiovascular (CVD) and kidney diseases.

Patients have been followed prospectively at the PsA clinic according to a standard protocol at 6- to 12-month intervals. We defined HUC in men > 450 µmol/l or women > 360 µmol/l. We matched patients with HUC based on sex and age ± 5 years with normal uric acid patients. Demographics information and disease characteristics were reviewed. Outcomes of patients with HUC, especially CVD and kidney diseases, were recorded. Conditional logistic regression was performed to determine factors independently associated with HUC in patients with PsA.

There were 325 (31.9%) out of 1019 patients with PsA who had HUC. Of these, 318 cases were matched to 318 controls. There were 11 (3.4%) out of 325 patients with HUC who had gout. Patients with HUC had longer disease duration and a higher Psoriasis Area and Severity Index. They had more concurrent comorbidities, including CVD and metabolic diseases, as well as higher prevalence of kidney stones and higher creatinine. Only 1 patient with HUC was treated with allopurinol at first evaluation visit and 7 patients during followup. Over the followup, 163 of the 318 patients had persistent HUC (pHUC) for more than 2 visits. Patients with pHUC developed more myocardial infarction, heart failure, and renal impairment. Multivariate analysis showed an association between pHUC, PsA disease duration, and obesity.

HUC is common in patients with PsA, especially in those with longer disease duration and obesity. Proper control of HUC and metabolic diseases may play a preventive role in improving PsA outcomes.