Risk of non-alcoholic fatty liver disease in patients with psoriasis: a systematic review and meta-analysis

Psoriasis has been linked to an increased risk of metabolic syndrome (MetS). Non-alcoholic fatty liver disease (NAFLD), the hepatic manifestation of MetS, is now the commonest liver disease worldwide and can evolve into cirrhosis in a subgroup of patients. Psoriasis has been reported to be associated to NAFLD.

The aim of this study was to evaluate the strength of the association between psoriasis and NAFLD.

A systematic review of the literature was conducted in six databases (Medline, CINAHL, Scopus, LILACS, Cochrane Library and EMBASE). Data from studies assessing frequency of NAFLD in psoriatic and non-psoriatic patients were extracted and meta-analysed using the Mantel-Haenszel method. Subgroups analysis of patients with psoriatic arthritis and moderate to severe psoriasis was also performed.

Seven case-control studies were included, all of them of low or moderate quality. Psoriatic patients exhibited an increased risk of NAFLD compared to non-psoriatic controls (six studies; n = 267,761 patients; odds ratio (OR): 2.15, 95% CI: 1.57-2.94). The association remained significant (OR: 2.07, 95% CI: 1.62-2.64) when only high/moderate quality studies were analysed (three studies; n = 3345 patients). The risk of NAFLD was significantly greater in patients with psoriatic arthritis (three studies; n = 505 patients; OR: 2.25, 95% IC: 1.37-3.71) and in patients with moderate to severe psoriasis compared to those with mild psoriasis (two studies; 51,930 patients, OR: 2.07, 95% CI: 1.59-2.71).

Data quality and heterogeneity may restrict the interpretation of the pooled risk estimates.

Case-control studies support an association between psoriasis and NAFLD. Screening of NAFLD in this group of patients may be warranted.