Liver test abnormalities in patients admitted for severe psoriasis: prevalence and associated risk factors.

BACKGROUND

Few epidemiologic data are available regarding biologic liver abnormalities during psoriasis flares.

OBJECTIVE

The aim of this study was to assess the prevalence of biological liver test abnormalities (LTA) in a psoriasis population and the risk factors associated with LTA.

METHODS

A retrospective cross-sectional study in four hospital dermatology tertiary care centres included patients admitted for severe psoriasis flare between 1st January 2010 and 31st December 2011. During the same period, a control population was selected comprising patients admitted for contact and/or atopic eczema. Data were collected on hospital records and biology software. LTA was defined as serum AST and/or ALT and/or ALP concentration above the upper normal limit (UNL) and/or GGT concentration above 2 UNL. Prevalence of LTA with 95% confidence intervals (95% CI) was compared between the psoriatic and control populations. Factors associated with LTA at P < 0.05 were considered for the final multivariate logistic regression model.

RESULTS

Two hundred and forty psoriasis patients and 96 eczema control patients were included. One hundred and fifty-five(64.6%) of the psoriasis patients were male, aged 55 years on average (±17.6); 192 (80.0%) had plaque-type psoriasis (PV) and 52 (21.6%) had localized (n = 32) or generalized (n = 20) pustular psoriasis (PP). Prevalence of LTA was 36% (95% CI, 30-42) in the psoriatic population, significantly higher than in controls (17%, 95% CI 9.5-25). Risk factors independently associated with LTA comprised PV (OR 3.79; 95% CI 1.48-9.65), PP (OR 3.80; 95% CI 1.40-10.25) and previously diagnosed liver disease (underlying hepatic steatosis, viral hepatitis or excessive alcohol consumption) (OR 3.88; 95% CI 2.02-7.45). No association was found with systemic antipsoriatic drug therapies.

CONCLUSIONS

In severe psoriasis, liver impacting comorbidities and/or specific psoriatic inflammation, the latter mostly in PP cases, more than drug-related liver toxicity, appears to predominantly account for LTA. Clinicians should be aware of this, to avoid unjustified withdrawal of useful systemic drugs.