Diagnostic performance of Gamma-Glutamyl Transferase (GGT) and mean corpuscular volume as biomarkers of alcohol use disorder in a Sub-Saharan African population: A cross-sectional study in Bukavu, eastern Democratic Republic of the Congo

ABSTRACT Introduction: Gamma-glutamyl transferase (GGT) and mean corpuscular volume (MCV) are the most widely available indirect biomarkers of chronic alcohol consumption. However, their diagnostic performance has rarely been evaluated in Central African populations, where drinking patterns, nutritional status, and the prevalence of confounding hepatic or hematological conditions may differ markedly from those in high-income countries. Material and methods: We conducted a cross-sectional analytical study among 100 adults (58 alcohol users and 42 non-drinking controls) recruited in Bukavu, eastern Democratic Republic of the Congo (DRC). Alcohol use disorder was defined using clinical interview criteria. Serum GGT activity was measured by spectrophotometry and MCV was determined using an automated haematology analyser (Sysmex). Receiver Operating Characteristic (ROC) curve analysis was used to assess diagnostic accuracy, sensitivity, specificity, and the area under the curve (AUC) were computed. Non-parametric tests (Mann–Whitney U and Kruskal–Wallis) were used between-group comparisons, with statistical significance set at p<0.05.