[Clinical significance of microalbuminuria in elderly diabetic patients]

To clarify the clinical significance of microalbuminuria in elderly diabetic patients, 167 diabetic patients were divided into two groups, 81 elderly patients aged 65 or more (mean age +/- SD: 72 +/- 9, 31 men and 50 women) and 86 middle-aged patients less than 65 years (mean age +/- SD: 56 +/- 8, 49 men and 37 women). We then examined the prevalence of microalbuminuria and other clinical parameters in both groups. The duration of diabetes (10 +/- 7 vs 9 +/- 7 years), body mass index (24.3 +/- 4.1 vs 23.9 +/- 3.5) and the levels of fasting plasma glucose (142 +/- 38 vs 144 +/- 40 mg/dl), HbA1c (7.4 +/- 1.6 vs 7.8 +/- 1.6%), plasma cholesterol (203 +/- 34 vs 212 +/- 46 mg/dl) and triglyceride (117 +/- 57 vs 121 +/- 67 mg/dl) showed no significant difference between elderly and middle-aged patients. However, the prevalence of microalbuminuria (30 < or = urinary albumin level < 300 mg/g.Cr), macroangiopathies involving cerebrovascular disease, ischemic heart disease and atherosclerosis obliterans, and hypertension were higher in elderly patients than those in the middle-aged patients (43.2 vs 20.0%, chi 2 = 10.39, p < 0.01, 29.6 vs 10.5%, chi 2 = 9.66, p < 0.01, 42.0 vs 24.4, chi 2 = 5.82, p < 0.05, respectively). Microalbuminuria in elderly patients may be caused not only by diabetic glomerular changes but also by glomerular changes due to aging and hypertension. Microalbuminuria, macroangiopathies and hypertension in elderly diabetic patients may develop interrelatedly depending on common vascular damages due to diabetes and aging.