The relationship between albuminuria and hypercholesterolemia.

BACKGROUND

To test the hypothesis that the albuminuria is an independent risk factor for hypercholesterolemia.

METHODS

Cross-sectional study (The Third National Health and Nutrition Examination Survey (NHANES III), 1988-1994) of the civilian, noninstitutionalized US population. Of the total 33,994 NHANES III participants, those aged 17 years or more and those who had complete urinary albumin-to-creatinine (UAC) ratio information formed our primary study population (n=17,702). The main outcomes of interest were: high serum TC level, defined as levels more than 6.2 mmol/L (240 mg/dL); high serum LDL cholesterol level, defined as levels more that 4.1 mmol/L (160 mg/dL); and low serum HDL cholesterol level, defined as levels less that 0.9 mmol/L (35 mg/dL).

RESULTS

Compared to individuals with normoalbuminuria, the odds ratio (OR) of high serum TC level and high LDL cholesterol level were respectively 1.04 and 1.32 for those with microalbuminuria, and 1.96 and 1.69 for those with macroalbuminuria. Increasing quintiles of UAC ratio was associated with graded increase in the odds of high serum TC (OR, 1,1.23,1.25,1.33,1.46; p trend=0.02) and LDL cholesterol (OR, 1, 0.99, 1.09, 1.46, 1.59; p trend=0.02) levels. In our analyses, the fourth quintile of UAC ratio was associated with significant OR of hypercholesterolemia, despite it being in the currently accepted normal range. However, albuminuria was not associated with low HDL cholesterol in our analysis.

CONCLUSIONS

Increasing albuminuria is associated with continuous, and graded increase in the odds of high serum TC and LDL cholesterol levels. Our results call for future follow-up studies to confirm if albuminuria precedes the development of hypercholesterolemia.