[Reduced estimated glomerular filtration rate and proteinuria are associated with increased cardiovascular events rate in octogenarian population]

To determine the relationship between estimated glomerular filtration rate (eGFR) and proteinuria with cardiovascular events in subjects aged 80 years or older.

Data for this retrospective prognostic study were drawn from the patient database for routine checkup in Beijing hospital between January 2001 to December 2001. Baseline eGFR and proteinuria were evaluated in 340 subjects [mean age: (85.6 ± 4.0) years]. eGFR was calculated using the modified abbreviated MDRD equations based on the Chinese chronic kidney disease patients. The subjects were divided into normal renal function group and reduced renal function group (eGFR <60 ml·min(-1)·1.73 m(-2)). The subjects were divided into subjects without proteinuria and subjects with proteinuria group. Cardiovascular events included cardiovascular death, nonfatal myocardial infarction, nonfatal stroke.

The proportion of reduced renal function was 36.8% (125/340). The proportion of proteinuria was 10.3% (35/340). The proportion of reduced renal function or proteinuria was 41.8% (142/340). Follow-up time was 79 months (40-114 months). Cardiovascular events rate was significantly higher in reduced renal function group than in normal renal function group [37.6% (47/125) vs. 26.2% (55/210), P < 0.05 ] and in proteinuria group than in without proteinuria group [50.0% (17/34) vs. 28.2% (85/301), P < 0.01 ]. Cox multivariate analysis revealed that both eGFR (HR = 0.978, 95%CI:0.961-0.994, P < 0.05 ) and proteinuria (HR = 2.049, 95%CI:1.132-3.709, P < 0.05) were independent risk factors for cardiovascular events after adjusting for age, gender, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, uric acid, hypertension, coronary heart disease, diabetes mellitus.

Reduced eGFR and presence of proteinuria are independent risk factors for cardiovascular event in subjects aged 80 years or older. eGFR and proteinuria can thus be used for cardiovascular event risk stratification in subjects aged 80 years or older.