Clinical value of detecting microalbuminuria as a risk factor for pregnancy-induced hypertension in insulin-treated diabetic pregnancies

Abstract

Objective: We evaluated the role of clinical non-overt stage III diabetic nephropathy concerning the development of more frequent hypertensive complications during pregnancies of women requiring insulin. Methods: 122 unselected pregnant women treated with insulin were enrolled in the study, of whom 56 were type-1 diabetic patients and 66 patients had gestational diabetes. In 24-h urine samples, excretion rates of albumin (UAE) and β2-microglobulin were determined by nephelometric analysis and a radioimmunoassay, respectively. These parameters were also measured in the serum as well as HbA1c, fructosamine and daily blood glucose profiles. Results: Sixteen (15.7%) women had an elevated UAE (>30 mg/24 h), of whom three had macroalbuminuria (UAE>300 mg/24 h). Thirteen (12.7%) insulin-treated women showed microalbuminuria during pregnancy, eight with type-1 diabetes and five with gestational diabetes requiring insulin. In the entire group hypertension was observed in seven (6.9%) women of whom six had microalbuminuria. The sensitivity and specificity were 85.7% and 92.6%, respectively.The positive predictive value reached 46.2%, whereas the negative predictive value was 98.9%. Conclusion: Measurement of UAE in diabetic pregnancies seems to be an useful additional parameter for risk evaluation of hypertensive disorders.