# Alanine transferase levels (ALT) and triglyceride-glucose index are risk factors for type 2 diabetes mellitus in obese patients

## TL;DR

Elevated liver enzyme ALT and a triglyceride-glucose index are linked to a higher risk of developing type 2 diabetes in obese patients.

## Contribution

The study shows that elevated ALT levels are a risk factor for type 2 diabetes in obese individuals, independent of traditional risk factors.

## Key findings

- T2DM developed in 136 subjects, with a significant difference between the first and fourth ALT quartile.
- ALT quartiles were associated with incident T2DM in both univariate and stepwise regression analyses.
- Traditional risk factors like triglyceride-glucose index and metabolic syndrome had greater predictive value than ALT.

## Abstract

The role of liver steatosis and increased liver enzymes (ALT) in increasing incident type 2 diabetes mellitus (T2DM) is debated, because of their differential effects on different ethnicities and populations. The aim of this study was to evaluate the role of elevated ALT in the development of T2DM in non-diabetic obese subjects receiving routine medical treatment.

A total of 1005 subjects [296 men and 709 women, aged 45.7 ± 13.12 years, body mass index (BMI) 39.5 ± 4.86 kg/m2] were followed for a mean period of 14.3 ± 4.44 years. Subjects were evaluated for several metabolic variables, including the triglyceride-glucose index and the presence of metabolic syndrome (IDF 2005 definition), and were subdivided into ALT quartiles.

T2DM developed in 136 subjects, and the difference was significant between the first and the fourth ALT quartile (p = 0.048). Both at univariate analysis and at stepwise regression, ALT quartiles were associated with incident T2DM. Traditional risk factors for T2DM coexisted, with a somehow greater predictive value, such as triglyceride-glucose index, age, arterial hypertension, LDL-cholesterol, and metabolic syndrome.

These data suggest an association between elevated ALT levels and the risk of incident T2DM in obesity.