Association between quality and quantity of dietary carbohydrate and pregnancy-induced hypertension: A case–control study

Abstract

Pregnancy-induced hypertension (PIH) is a pregnancy-specific disorder that increases maternal and infant mortality and morbidity. The quantity and quality of consumed carbohydrates are probably the main dietary factors affecting blood pressure. The present study aimed to evaluate the association of carbohydrate quality and quantity with PIH. This case-control study was performed on 202 pregnant women with or without PIH. The dietary data were collected using 168-item semi-quantitative food frequency questionnaires. Daily glycemic index (GI) and glycemic load (GL), ratio of whole grains to total grains, ratio of solid carbohydrates to total carbohydrates, dietary fiber and carbohydrate intake, and carbohydrate quality index (CQI) were calculated and their associations with PIH were evaluated using logistic regression. We eliminated collinearity within independent variables using factor analysis and then with evaluating the relationship between extracted factors and PIH. In pregnant women in whom the daily carbohydrate intake and GL were higher than median increased frequency of PIH compared to whom had lower than median ones (OR=3.23, 95% CI 1.46-7.17, and P=0.004; OR=2.60, 95% CI 1.21-5.56; and P=0.035, respectively). Furthermore, we showed a significant inverse association between extracted factor that was mostly related to total fiber intake frequency of PIH (OR=0.45; 95% CI 0.20-0.97, and P=0.049 when higher than median values compared to lower than ones). The GI, ratio of whole grains to total grains, ratio of solid carbohydrates to total carbohydrates, and CQI did not associate with PIH. These findings suggest that carbohydrate intake and GL are related to higher and daily fiber intake to lower frequency of PIH.