Clinical Profile of Psoriasis Patients With Comorbid Fatty Liver and Risk Factors for Advanced Liver Fibrosis in Those With Metabolic Dysfunction–Associated Steatotic Liver Disease

Psoriasis is increasingly regarded as a systemic inflammatory disease rather than a condition confined to the skin. It is commonly associated with comorbidities such as metabolic syndrome, cardiovascular disease, and hepatic disorders. Among these, fatty liver is one of the most frequently observed hepatic comorbidities in psoriasis patients; however, the prognosis of patients with both psoriasis and fatty liver has not been fully elucidated. This is a single-center retrospective study aimed at elucidating the characteristics of Japanese patients with psoriasis comorbid with fatty liver and identifying predictive factors for advanced liver fibrosis. A total of 89 psoriasis patients were enrolled in this study, including 64 with psoriasis vulgaris, 24 with psoriatic arthritis (PsA), and 1 with generalized pustular psoriasis. All patients underwent abdominal computed tomography to assess the presence of fatty liver. We compared clinical and laboratory parameters between patients with fatty liver and those without. Psoriasis patients with comorbid fatty liver were significantly younger and had higher body mass index (BMI), psoriasis and area severity index scores, serum C-reactive protein, alanine aminotransferase, aspartate aminotransferase, hemoglobin A1c, and triglyceride levels, and prevalence of diabetes mellitus (DM) compared to those without fatty liver. Other than them, in patients with PsA, the higher frequency of multiple biologic switches was found. Among patients with fatty liver who met the diagnostic criteria for metabolic dysfunction-associated steatotic liver disease (MASLD), those with comorbid DM exhibited a significantly higher Fibrosis-4 index compared to those without DM. The exploratory analysis of predictive factors for high-risk liver fibrosis in patients with psoriasis and MASLD identified age ≥ 57 years, BMI ≥ 24.8, and comorbid DM as significant risk factors. In conclusion, psoriasis patients with comorbid fatty liver and components of metabolic syndrome, such as obesity and DM, should be considered for referral to a hepatology specialist.