Tight control of A1C, blood pressure, lipids delays onset of diabetic nephropathy, study findings suggest

Intensively treating patients with diabetes to achieve American Diabetes Association-recommended targets for hemoglobin A1C, blood pressure (BP), and lipids significantly lowers their risk of new-onset microalbuminuria, suggesting such treatment can delay or prevent diabetic nephropathy, new data from a study conducted in Taiwan reveal. The longitudinal cohort study included 1,290 patients with type 2 diabetes, normoalbuminuria, and normal plasma creatinine levels at baseline (men, n=578;...

Intensively treating patients with diabetes to achieve American Diabetes Association-recommended targets for hemoglobin A1C, blood pressure (BP), and lipids significantly lowers their risk of new-onset microalbuminuria, suggesting such treatment can delay or prevent diabetic nephropathy, new data from a study conducted in Taiwan reveal.

The longitudinal cohort study included 1,290 patients with type 2 diabetes, normoalbuminuria, and normal plasma creatinine levels at baseline (men, n=578; mean age, 63 years; mean duration of diabetes, 10.1 years). During the study, the participants were treated to achieve A1C levels <7%, systolic BP <130 mm Hg, diastolic BP <80 mm Hg, LDL cholesterol levels <100 mg/dL, triglyceride levels <150 mg/dL, and HDL cholesterol levels >40 mg/dL in men and >50 mg/dL in women, with follow-up visits scheduled every 3 to 6 months.

During a mean follow-up of 3.8 years, 211 patients (16.4%) developed new-onset microalbuminuria.

The data showed that the patients who achieved target levels for systolic BP, A1C, or HDL cholesterol during follow-up were significantly less likely to develop new-onset microalbuminuria. Specifically, achieving a systolic BP <130 mg/dL was associated with a 35% reduction in risk, achieving an A1C level <7% was associated with a 27% reduction in risk, and achieving appropriate levels of HDL cholesterol was associated with a 28% reduction in risk in an analysis adjusted for age, sex, medication use, and body mass index.

When the analysis was further adjusted for baseline variables, including systolic BP, diastolic BP, A1C, lipids, creatinine, diabetes duration, albumin-creatinine ratio, and estimated glomerular filtration rate, these associations were attenuated. In this analysis, only a systolic BP <130 mg/dL was associated with a significant reduction in risk; the patients who achieved this systolic BP target during follow-up were 26% less likely to develop new-onset microalbuminuria relative to those who did not reach this goal.

Of the three goals associated with a significantly reduced risk of microalbuminuria (systolic BP, A1C, and HDL cholesterol), 8.1% of the participants achieved all 3 goals during follow-up, 71.4% achieved 1 or 2 of these goals, and 20.5% achieved none of these goals. The patients who achieved 2 or 3 goals were significantly less likely to develop microalbuminuria relative to those who achieved none. (Tu S-T, et al. Arch Intern Med 2010;170:155-161.)