Impact of Metformin Use on Liver Function Tests in Diabetic Patients With Suspected Non-Alcoholic Fatty Liver Disease (NAFLD): A Cross-Sectional Analysis.

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is highly prevalent among patients with type 2 diabetes mellitus (T2DM) and is often associated with elevated liver enzymes.

OBJECTIVE

To assess the impact of metformin use on liver function tests in diabetic patients with clinically suspected NAFLD.

METHODS

This was a cross-sectional analytical study conducted at Jinnah Hospital, Lahore, Pakistan, from July 2024 to December 2024. A total of 185 adult patients were enrolled in the study. Non-probability consecutive sampling was used to recruit participants who met the inclusion criteria. Demographic data, including age, gender, body mass index (BMI), and duration of diabetes, were recorded. Clinical records were reviewed to document metformin use (yes/no), dosage, and duration.

RESULTS

Out of 185 patients, 115 (62.2%) were metformin users and 70 (37.8%) were non-users. Metformin users had significantly lower mean alanine aminotransferase (ALT) (41.3 ± 14.6 IU/L vs. 54.7 ± 18.2 IU/L; p < 0.001) and aspartate aminotransferase (AST) levels (35.2 ± 12.4 IU/L vs. 44.6 ± 15.7 IU/L; p = 0.002) compared to non-users. No significant differences were observed in alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT) levels. Elevated ALT and AST were significantly less frequent in metformin users (p < 0.01). A weak inverse correlation was observed between metformin dose and ALT levels (r = -0.19, p = 0.043).

CONCLUSION

It is concluded that metformin use is associated with improved liver enzyme profiles in diabetic patients with suspected NAFLD. These findings suggest a potential hepatoprotective role for metformin, warranting further longitudinal studies to explore its impact on liver histology and long-term hepatic outcomes.