Objective To evaluate baseline predictors for the development of persistent microalbuminuria and macroalbuminuria prospectively in patients with type 1 diabetes.

Our long-term prospective study of type 2 diabetic patients with nephropathy has revealed several modifiable risk factors of enhanced progression in kidney disease and increased mortality.

OBJECTIVE -Conflicting evidence of a decline in incidence of microvascular complications in type 1 diabetes during the last decades has been reported. To assess recent trends in the cumulative incidence of diabetic microangiopathy in type 1 diabetes, we analyzed data from long-term prospective observational studies lasting Ն20 years. RESULTS -In patients followed for Ն20 years, the cumulative incidence (95% CI) of diabetic nephropathy after 20 years of diabetes (urinary albumin excretion Ͼ300 mg/24 h) was reduced in patients with more recent diabetes onset (groups A-D): 31.1% (22.5-39.7) vs. 28.4% (19.8 -37.0) vs. 18.9% (10.9 -26.9) vs. 13.7% (6.2-21.2) (P ϭ 0.015). Similarly, the cumulative incidence of proliferative retinopathy was as follows: 31.2% (22.2-39.8) vs. 30.3% (22.2-38.4) vs. 19.3% (11.2-27.4) vs. 12.5% (5.2-19.8) (P Ͻ 0.01). In the latter groups, antihypertensive treatment was started earlier, blood pressure and HbA 1c were lower, and fewer patients smoked. RESEARCH DESIGN AND METHODSCONCLUSIONS -Our study demonstrates a decrease in the cumulative incidence of diabetic microangiopathy in type 1 diabetes over the past 35 years. Improved glycemic control, lower blood pressure (in part due to early aggressive antihypertensive treatment), and reduced prevalence of smoking rates were associated with the improved prognosis.

The prognosis of diabetic nephropathy has improved during the past decades, predominantly because of effective antihypertensive treatment. Genuine normotensive patients have a slow progression of nephropathy. Several modifiable variables have been identified as progression promoters.