INSULIN-RESISTANCE AND INCREASED BODY-MASS INDEX IN WOMEN DEVELOPING HYPERTENSION IN PREGNANCY

Background and Aim: Several retrospective studies have suggested that women who develop hypertension during pregnancy characteristically hav e insulin resistance and obesity, but this interrelationship has not b een studied prospectively. Methods and Results: Young women presenting for prenatal care were clinically evaluated and had a Glucose Toleran ce Test (GTT) at approximately 19 weeks' gestation. Serum insulin, C-p eptide and glucose were measured 1 hour after a 50-gram oral glucose l oad. Subsequently, the patients were classified as normal, gestational hypertensives or preeclamptics, by standard criteria. Of the 164 wome n who had oral glucose tolerance testing and who delivered at an urban medical center, eleven developed hypertension in pregnancy. Three of these 11 hypertensives had proteinuria and other clinical characterist ics of preeclampsia. At the time at which the oral glucose tolerance s tudy was conducted (approximately 19 weeks), the group who developed h ypertension had a greater body mass index (BMI) 37+/-3 vs 26+/-0.6) (p <0.001), greater 1-hour insulin (93+/-16 vs 16+/-3 mU/ml) and glucose (126+/-8 vs 98+/-2 m/dl) (p<0.005) levels than those women not develop ing hypertension. Stepwise discriminant function analysis revealed tha t the characteristic at the time of the oral GTT that was the most sig nificant predictor for the development of hypertension in pregnancy wa s BMI. Conclusions: Women who develop new-onset hypertension in pregna ncy have greater BMI, as well as evidence of insulin resistance in the second trimester than women who remain normotensive. Elevated BMI in the second trimester of pregnancy is a strong predictor of development of new-onset hypertension in pregnancy in this population of largely African American urban women. (C) 1996, Medikal Press.