Abstract
Objective We aimed to determine the prevalence and incidence, and identify the factors associated with liver abnormalities in patients with psoriatic arthritis (PsA).
Methods From a longitudinal cohort study we identified PsA patients with either elevated serum transaminase or alkaline phosphatase levels or liver disease after the first visit to the PsA clinic (cases). Controls were subjects from the same cohort who never had such abnormalities or liver disease. Cases and controls were matched 1:1 by sex, age at the first clinic visit, and follow-up duration, variables at the onset of the first appearance of liver test abnormality associated with liver abnormalities were identified using univariate logistic and multivariate logistic regression analyses.
Results Among 1061 patients followed in the PsA clinic, 343 had liver abnormalities. 256 patients who developed liver abnormalities after the first visit were identified as cases, 718 patients were identified as controls. The prevalence of liver abnormalities was 32% and the incidence was 39/1000 patient-years where there were 256 cases over 6533 total person years in the PsA cohort. Liver abnormalities were detected after a mean (s.d.) follow up duration of 8.3 ±7.8 years. The common causes of liver abnormalities were drug- induced hepatitis and fatty liver. Higher BMI, daily alcohol intake, higher damaged joint count, elevated CRP, use of methotrexate (MTX), leflunomide (LFN) or TNF inhibitors were independent factors associated with liver abnormalities.
Conclusion Liver abnormalities are common among patients with PsA and are associated with higher BMI, more severe disease and certain therapies.