Prevalence of Non-Alcoholic Fatty Liver Disease (NAFLD) Diagnosed by Controlled Attenuation Parameter on Transient Elastography and Its Predisposing Factors in Psoriasis

Background: Psoriasis patients have an increased risk for non-alcoholic fatty liver disease (NAFLD). Controlled attenuation parameter (CAP) on transient elastography is more sensitive than abdominal ultrasonography in detecting liver steatosis. Objectives: To determine the prevalence of NAFLD in psoriasis and to identify its predisposing factors. Methods: A cross-sectional study was performed involving 109 psoriasis patients aged > 18 years in two tertiary dermatology clinics in Kuala Lumpur. Patients on hepatotoxic drugs, had excessive alcohol intake, and other secondary causes of chronic liver diseases were excluded. Anthropometrics, blood pressure, Psoriasis Area and Severity Index (PASI), liver function test, lipid profile, and fasting blood glucose were obtained. CAP on transient elastography was performed to diagnose NAFLD. The clinical characteristics of psoriasis patients were compared between patients with and without NAFLD. Results: The prevalence of NAFLD was 85.3%. NAFLD in psoriasis patients was associated with a higher weight (P < 0.0005), body mass index (BMI) (P < 0.0005), waist circumference (P < 0.0005), and metabolic syndrome (P = 0.002). Fasting blood glucose (5.3 [1.8] mmol/L, p=0.010), triglyceride (1.4 [0.8] mmol/L, P < 0.0005), and alanine transaminase (28.5 [26] U/L, P = 0.001) were higher in patients with NAFLD compared with those without it. PASI and systolic blood pressure correlated significantly with NAFLD severity. BMI (OR = 1.63, 95% CI: 1.127 - 2.357, P = 0.009), triglyceride level (OR = 130.74, 95% CI = 2.94 - 812, P = 0.012), and PASI (OR = 1.138, 95% CI = 1.004 - 1.290, P = 0.043) were the significant predictors of NAFLD. Conclusions: NAFLD should be screened in all psoriasis patients, especially in patients with high BMI, metabolic syndrome, and severe psoriasis, despite having a normal biochemical profile. Early detection of asymptomatic NAFLD is essential for preventive management, including to reduce hepatotoxicity risk of psoriasis pharmacotherapy.