Pre-eclampsia but not pregnancy-induced hypertension is a risk factor for diabetic nephropathy in type 1 diabetic women

Aims/hypothesis Our aim was to study whether pre-eclampsia and pregnancy-induced hypertension are predictors of diabetic nephropathy in type 1 diabetic women. Materials and methods A total of 203 type 1 diabetic women, who were pregnant between 1988 and 1996 and followed at the Department of Obstetrics and Gynaecology in Helsinki, were re-assessed after an average of 11 years within the nationwide, multi-centre Finnish Diabetic Nephropathy Study. Diabetic nephropathy was defined as microalbuminuria, macroalbuminuria or end-stage renal disease. Results Patients with prior pre-eclampsia had diabetic nephropathy more often than patients with a normotensive pregnancy (diabetic nephropathy vs normal albumin excretion rate: 41.9% vs 8.9%; p < 0.001), whereas patients with a history of pregnancy-induced hypertension did not (10.3% vs 8.9%; p=0.81). CHD was more prevalent in patients with a history of pre-eclampsia than in patients with a normotensive pregnancy (12.2% vs. 2.2%; p=0.03). Pre-eclampsia (odds ratio [OR] 7.7, 95% CI 1.6-36.1; p=0.01) and HbA(1c) (OR 2.0, 95% CI 1.1-3.8; p < 0.05) were associated with incident diabetic nephropathy even when adjusted for follow-up time, BMI, smoking, diabetes duration and age. Conclusions/interpretation These data suggest that a history of pre-eclamptic pregnancy but not pregnancy-induced hypertension is associated with an elevated risk of diabetic nephropathy.