Association between gamma-glutamyltransferase and albuminuria in nondiabetic adults with normal renal function

Serum gamma-glutamyltransferase (GGT) has been associated with albuminuria in diabetes patients, but it has not been investigated in the general population. We aimed to investigate the association between serum GGT and albuminuria in the nondiabetic Korean population with normal kidney function.

Study participants (3948; 1549 men and 2399 women) with an estimated glomerular filtration rate ≥60 mL/min/1.73 m² were analyzed from the fifth Korean National Health and Nutrition Examination Survey (2011). Albuminuria was defined as an albumin-creatinine ratio >30 mg/g. Serum GGT was analyzed by dividing into quartiles. Multiple logistic models were used to analyze the associations between GGT and albuminuria.

The prevalence of albuminuria was 5.1% and increased linearly according to increasing GGT quartiles (P for trend = 0.005). A linear regression analysis revealed that GGT was positively related with albuminuria (P = 0.008). After adjusting for confounding factors, the odds ratio for albuminuria was 1.80 (95% CI 1.079-3.010, P for trend = 0.029) for the highest quartile group compared with those observed in the lowest quartile of GGT. In addition, this independent relationship did not change when the cut-off value of GGT (30 IU/L) was applied to this analysis. Compared with GGT value ≤30 IU/L, the adjusted odds ratio of albuminuria in participants with GGT >30 IU/L was 1.96 (95% CI 1.319-2.906, P < 0.001).

Higher serum GGT levels within the reference range were significantly associated with albuminuria in nondiabetic Koreans with preserved kidney function, independently of traditional cardio-renal risk factors.