Association Between Serum Gamma-Glutamyl Transferase and Albuminuria As Markers Of Endothelial Dysfunction Among General Outpatients at Ruhoko Health Centre IV, Southwestern Uganda

Background Endothelial dysfunction is an early marker of cardiovascular and renal disease, emphasizing the need for accessible biomarkers for early detection. Serum gamma-glutamyl transferase (GGT) and albuminuria have both been proposed as indicators of endothelial damage. Unlike albuminuria, which can be influenced by urine concentration and collection methods, GGT is routinely measured using standardized assays, making it a potentially more practical tool. This study aimed to assess the association between serum GGT and albuminuria to explore the potential of GGT as a marker for early endothelial dysfunction. Methods A cross-sectional study was conducted among 200 general outpatients aged ≥ 18 years at Ruhoko Health Centre IV in Ibanda District, Southwestern Uganda. Socio-demographic and clinical data were collected using structured questionnaires and physical assessments. Venous blood was analyzed for serum GGT using a Humastar 100 Chemistry Analyzer. Spot urine samples were tested for albuminuria using the albumin-to-creatinine ratio (ACR) via semi-quantitative dipstick strips. Poisson regression was used to assess associations, with statistical significance set at p  ≤ 0.05. Results The prevalence of elevated serum GGT (> 55 U/L in males, > 30 U/L in females) was 21.5% (95% CI: 16.32–27.78), while albuminuria (ACR > 30 mg/g) was present in 71.5% of participants (95% CI: 64.81–77.36). Elevated serum GGT was positively associated with albuminuria in both crude (cPR = 1.13; 95% CI: 0.79–1.63; p  = 0.498) and adjusted models (aPR = 1.24; 95% CI: 0.84–1.83; p  = 0.284), although these associations were not statistically significant. No other demographic or clinical variables showed significant associations after adjustment. Conclusion This study reports a high prevalence of albuminuria and a non-significant yet positive association with elevated GGT among general outpatients. Although the cross-sectional design and semi-quantitative ACR testing limit causal inference, the findings suggest a potential link that warrants further investigation. Larger, longitudinal studies are recommended to validate these findings and assess the clinical utility of GGT as a marker for early endothelial dysfunction.