# Utilizing %Carbohydrate-deficient Transferrin as a Biomarker to Complement Interviews in Stratifying Alcohol Consumption in Patients with Alcohol Dependence: Aiming for Application to Fatty Liver Disease

## TL;DR

The study explores using %CDT as a blood test to better assess alcohol consumption in patients with alcohol dependence, which could improve care for those with fatty liver disease.

## Contribution

The study identifies specific %CDT cutoff values to stratify alcohol consumption in alcohol-dependent patients.

## Key findings

- %CDT values increase with higher alcohol consumption levels in men and women.
- Cutoff values of 1.67% and 2.48% correspond to alcohol consumption thresholds of 30/20 g/day and 60/50 g/day.
- Gamma-glutamyl transferase (GGT) and GGT-CDT struggle to distinguish lower alcohol consumption thresholds.

## Abstract

Alcohol dependence is linked to various issues, including not only alcohol-associated/related liver disease (ALD) but also social isolation, making the assessment of alcohol consumption crucial for patient management. Meanwhile, a multisociety consensus group has introduced a new classification for steatotic liver disease (SLD), including ALD, based on alcohol consumption. The evaluation of alcohol intake uses tools such as the Alcohol Use Disorders Identification Test and Lifetime Drinking History; however, these tools may lack accuracy in clinical settings. Carbohydrate-deficient transferrin (%CDT) is a quantitative and objective biomarker for alcohol consumption. Therefore, we aimed to determine %CDT values that stratify alcohol consumption.

This cross-sectional analysis included 285 serum samples from patients receiving inpatient or outpatient treatment at two specialized alcohol dependency medical centers. Participants were alcohol-dependent patients who underwent detailed interviews regarding alcohol consumption, biochemical blood tests, and %CDT testing.

Among the 285 samples, 32.6%, 19.6%, and 47.7% corresponded to alcohol consumption levels of ≤30 g/day for men/≤20 g/day for women, 30-60 g/day for men/20-50 g/day for women, and ≥60 g/day for men/≥50 g/day for women, respectively. %CDT values increased with increasing alcohol consumption (p < 0.05-0.0001). The cutoff values reflecting alcohol consumption of 30 g/day for men/20 g/day for women and 60g/day for men/50g/day for women were 1.67% and 2.48%, respectively. Gamma-glutamyl transferase (GGT) and GGT-CDT were able to distinguish between alcohol consumption above and below 60 g/day for men and 50 g/day for women (p < 0.0001). However, they had difficulty distinguishing between alcohol consumption above and below 30 g/day for men and 20 g/day for women.

%CDT, in conjunction with detailed interviews, can be used to detect alcohol consumption, particularly to distinguish whether it exceeds 30 g/day in men and 20 g/day in women. Applying this to the clinical management of patients with alcohol dependence accompanied by ALD or SLD may contribute to improving the quality of care.