Recent studies have demonstrated that the levels of adipocyte fatty acid-binding protein (A-FABP) are closely associated with diabetic kidney disease (DKD) in patients with type 2 diabetes mellitus (T2DM). This study aimed to examine the association between serum A-FABP level and rapid renal function decline in patients with T2DM and preserved renal function.

This was a prospective observational study of 452 patients with T2DM and preserved renal function who had serial measurements of estimated glomerular filtration rate (eGFR). Rapid renal function decline was defined as an eGFR decline of >4% per year. The association between baseline serum A-FABP level and rapid renal function decline was investigated.

Over a median follow-up of 7 years, 82 participants (18.1%) experienced rapid renal function decline. Median A-FABP levels were significantly higher in patients with rapid renal function decline, compared to non-decliners (20.2 ng/mL vs. 17.2 ng/mL, P=0.005). A higher baseline level of A-FABP was associated with a greater risk of developing rapid renal function decline, independent of age, sex, duration of diabetes, body mass index, systolic blood pressure, history of cardiovascular disease, baseline eGFR, urine albumin creatinine ratio, total cholesterol, glycosylated hemoglobin, high-sensitivity C-reactive protein and use of thiazolidinedione, insulin, angiotensin-converting-enzyme inhibitors and angiotensin II-receptor blockers and statin (odds ratio, 3.10; 95% confidence interval, 1.53 to 6.29; P=0.002).

A high level of serum A-FABP is associated with an increased risk of rapid renal function decline in patients with T2DM and preserved renal function. This suggests that A-FABP could play a role in the progression of DKD in the early stages.