The Steatosis-Associated Fibrosis Estimator (SAFE) score for assessing significant liver fibrosis in patients with psoriasis

Abstract

Background There is an urgent need for noninvasive tests to identify patients with psoriasis at risk of significant liver fibrosis. Objectives To externally validate the ability of the Steatosis-Associated Fibrosis Estimator (SAFE) score to detect significant liver fibrosis in patients with psoriasis using transient elastography (TE) as a reference. Methods We analysed data from 75 patients with psoriasis, including TE, SAFE score, Fibrosis-4 Index (FIB-4) and Nonalcoholic Fatty Liver Disease Fibrosis Score (NFS). Significant liver fibrosis was defined as TE values≥7.1 kPa. Diagnostic accuracy was assessed using the area under the receiver operating characteristic curve (AUROC). Results Fifteen patients (20%) exhibited significant liver fibrosis. The AUROCs for the SAFE and FIB-4 scores were 0.82 [95% confidence interval (CI) 0.67–0.97] and 0.62 (95% CI 0.45–0.79), respectively. The SAFE score outperformed the FIB-4 Index (P=0.01) but was comparable with the NFS (P=0.05) in predicting significant fibrosis. Using thresholds of<0, 0 to<100 and≥100, the SAFE score categorized 36, 24 and 15 patients into low, intermediate and high-risk groups for significant fibrosis, respectively. The negative predictive value for excluding significant fibrosis with a SAFE score of<0 was 94.4%, and the positive predictive value for diagnosing significant fibrosis with a SAFE score of>100 was 53.3%. The duration of psoriasis, joint involvement and methotrexate treatment did not affect the diagnostic ability of the SAFE score whereas age of the patient did. Conclusions The SAFE score demonstrated good accuracy in assessing clinically significant fibrosis among patients with psoriasis. This score should prove valuable for risk stratification and patient management in dermatology practice.