Low-grade albuminuria and incidence of cardiovascular disease and all-cause mortality in nondiabetic and normotensive individuals

Abstract

Background: Recent studies indicate that, in people with diabetes or hypertension and in the general population, low-grade albuminuria (LGA) below the microalbuminuria threshold is a predictor for incidence of cardiovascular disease (CVD) and mortality. However, it remains unclear whether LGA predicts the risk of CVD incidence and death in nondiabetic and normotensive individuals.

Methods: A total of 3599 individuals aged not less than 40 years from the general population who are free of CVD in nondiabetic and normotensive individuals with preserved glomerular filtration rate were followed for CVD incidence and all-cause death. LGA was defined as urinary albumin to creatinine ratio (UACR) less than 30 mg/g. It was examined whether there is an association between LGA and CVD incidence or all-cause death.

Results: During the average 5.9 years of follow-up, 61 individuals had first CVD events, and 85 individuals died. The hazard ratios (HRs) for CVD incidence and all-cause death after full adjustment by potential confounders increased significantly in the top tertile of LGA (UACR ≥ 9.6 mg/g for men, ≥ 12.0 mg/g for women) compared with the first tertile [HR = 2.79, 95% confidence interval (CI), 1.41-5.52, HR = 1.69, 95% CI, 1.00-2.84, respectively]. Population-attributable fractions of the top tertile of LGA for CVD incidence and all-cause death were 37.9 and 20.1%, respectively.

Conclusion: In apparently healthy individuals with optimal blood pressure and no diabetes, LGA independently predicts CVD incidence and all-cause death, particularly with the large contribution to the excessive incidence of CVD.