The increased prevalence of non-alcoholic fatty liver disease in psoriatic patients: a study from South India

Background: Psoriasis is an inflammatory disease of the skin and joints. Previous studies have shown a higher prevalence of metabolic syndrome (MS) in psoriatic patients. Recent studies show that non-alcoholic fatty liver disease (NAFLD) is also frequent in psoriasis patients.

Objectives: To investigate the occurrence and severity of NAFLD in South Indian psoriatic patients and healthy controls.

Methods: In phase 1 we performed a case control study on 333 adult psoriasis patients and 330 controls matched by age, sex and body mass index. NAFLD was diagnosed by ultrasonography and liver enzymes after excluding other liver diseases. In phase 2 we compared the NAFLD subgroups in psoriasis patients and controls by determining their fibrosis, steatosis and non-alcoholic steatohepatitis (NASH) scores.

Results: The occurrence of NAFLD was higher in psoriasis patients than in controls (17.4 vs 7.9%; P = 0.002). NAFLD patients in the psoriasis group (n = 58) were more likely to have MS (P = 0.03) and diabetes (P = 0.02) than those with psoriasis alone (n = 254). The former group had a longer duration of psoriasis and arthritis (P = 0.003 and 0.005). Psoriasis patients with NAFLD had more severe disease as per the psoriasis area and severity index scores (P = 0.02). Psoriasis patients had more severe NAFLD than controls as reflected by the steatosis, NASH and fibrosis scores (P = 0.001, 0.003, 0.03 respectively).

Conclusion: NAFLD is the commonest liver disease in Indian psoriatic patients when compared to controls. As NAFLD is more severe in psoriasis patients we suggest routine screening for NAFLD in this group especially when systemic therapy is considered.