Prevalence and metabolic determinants of abnormal alanine aminotransferase: A cross-sectional study of Iranian adults, 2018-2022

Abstract

Background: Alanine aminotransferase (ALT) is an enzyme whose activity became the principal biomarker for liver disease. In the current study, we aimed to determine the prevalence of abnormal ALT, as a surrogate of nonalcoholic fatty liver disease (NAFLD) and its associated determinants using different criteria among Tehranian subjects between 2018 and 2022.

Methods: This is a cross-sectional study on 5676 Tehranian individuals aged 20-70 years. The weighted prevalence of abnormal ALT was calculated using both the National Health and Nutrition Examination Survey in the United States (US-NHANCE; ALT ≥30 U/L for females and ≥40 U/L for males) and the American College of Gastroenterology (ACG) guideline (ALT >25 U/L for females, and >33 U/L for males) thresholds. Moreover, uni/multivariable logistic regression analysis was performed to find the determinants of abnormal ALT.

Results: The weighted prevalence of abnormal ALT was 12.8% (7.6% females and 18% males) and 22.5% (17.7% females and 27.3% males) based on US-NHANCE and ACG criteria, respectively. Our results showed every decade increase in age decreased the risk of abnormal ALT by 32%. We also found that generally male gender, being overweight/obese, central adiposity, TG ≥6.9 mmol/L, non-HDL-C ≥3.37 mmol/L, lipid-lowering medications, pre-diabetes/T2DM were associated with abnormal ALT using different cutoff points. Moreover, among men resting tachycardia (≥90 beats per min), hypertension, and females past-smoker were also found as other determinants of abnormal ALT.

Conclusion: High prevalence of abnormal ALT among non-elderly Iranian adults, especially among men, necessitates immediate multifaceted strategies by policymakers to prevent potential complications caused by NAFLD.

Keywords: alanine aminotransferase; logistic regression; metabolic determinants; prevalence.

FIGURE 1

Weighted prevalence of abnormal ALT in different subgroups based on the 7th examination (2018–2022) of TLGS data. ALT, Alanine aminotransferase; TLGS, Tehran lipids and glucose study. US‐NHANCE cut point for abnormal ALT: ALT >40 U/L for male and >31 U/L for female. ACG clinical guideline for abnormal ALT: ALT >33 U/L for male and >25 U/L for female.