Development and validation of the HABIT score: a practical and robust tool to predict hepatic steatosis using HbA1c, BMI, and triglycerides in patients with unexplained elevated liver enzymes.

INTRODUCTION AND

OBJECTIVES

Unexplained elevated liver enzymes (ELE) are common and often linked to metabolic dysfunction-associated steatotic liver disease (MASLD). Diagnosis in primary care is difficult due to limited access to advanced imaging, highlighting the need for simple non-invasive tools. This study aimed to develop and validate a pragmatic, laboratory-based score to predict hepatic steatosis in patients with unexplained ELE.

PATIENTS AND

METHODS

A derivation cohort of 206 patients with 40 classified as steatosis-positive with a NAFLD Activity Score (NAS) ≥4 was analysed. Candidate predictors were tested by univariate analysis and entered into multivariate logistic regression. Regression coefficients were scaled to construct an integer-based score (HABIT). Validation was performed in a retrospective cohort of patients with unexplained ELE attending our hepatology clinic between 2019 and 2021 (n = 648), all undergoing standardized diagnostic work-up including ultrasound, elastography, and laboratory testing.

RESULTS

Multivariate analysis identified HbA1c, body mass index (BMI), and triglycerides as independent predictors of steatosis. The HABIT score was derived as: (61 × HbA1c [%]) + (3 × BMI [kg/m²]) + Triglycerides [mg/dL]. Diagnostic accuracy was high in the derivation cohort (AUROC: 0.83) and robust in validation (AUROC: 0.81), outperforming the Hepatic Steatosis Index (HSI, AUROC: 0.77). Cut-offs <490 and >630 reliably ruled out (sensitivity 93.6 %) or confirmed (specificity 92.5 %) steatosis. Score values correlated significantly with ultrasound grades and CAP.

CONCLUSIONS

The HABIT score is a simple, robust tool for identifying hepatic steatosis in unexplained ELE. It outperforms HSI and may facilitate early detection and risk stratification in primary care with limited diagnostic resources.