Association between urinary C-megalin levels and progressive kidney dysfunction: a cohort study based on the diabetes distress and care registry at Tenri (DDCRT 24)

AimsThe aim of this cohort study was to evaluate the association between urinary levels of C-megalin, a full-length form of megalin, and kidney dysfunction progression and its dependence on the urinary albumin-creatinine ratio (UACR) in individuals with diabetes.MethodsWe enrolled 1,547 individuals with diabetes who visited the ambulatory clinic at Tenri Hospital, a regional tertiary-care hospital in Tenri City, Nara Prefecture, Japan, with an estimated glomerular filtration (eGFR) of & GE; 30 mL/min/1.73 m(2). The hazard ratio (HR) and 95% confidence interval (CI) were estimated using Cox proportional hazard models to examine the association between urinary C-megalin levels and eGFR decline by & GE; 40% from baseline.ResultsUrinary C-megalin level was not associated with & GE; 40% eGFR decline in an age-, sex-, eGFR-, systolic blood pressure-, hemoglobin-, and UACR-adjusted model in the 1,547 patients enrolled in the study. However, urinary C-megalin levels were associated with a & GE; 40% decline in eGFR when accounting for the relationship between urinary C-megalin levels and UACR in the model. This association was UACR-dependent.ConclusionsHigh urinary C-megalin levels were associated with progressive kidney dysfunction in individuals with diabetes, and this association was attenuated by high UACRs.