The Association Between Dietary Patterns And Preeclampsia:A Case-Control Study

ObjectiveThis study was conducted to explore the association between dietary patterns and the odds of preeclampsia(PE)in pregnant women in both dietary index method and factor analysis method,find out the dietary pattern that may influence the occurrence and development of PE,and provide theoretical basis for guiding reasonable diet during pregnancy and preventing the occurrence of PE.MethodsThis 1:1 matched case-control study was conducted from March 2016 to June 2019 at Department of Obstetrics in the First Affiliated Hospital of Zhengzhou University.A total of 440 cases with PE and 440 controls without hypertension or proteinuria were included in this study.The two groups were matched according to age(±3),gestational age(±1)and GDM(yes/no).The information about sociodemographic characteristics,living habits and physical activities was obtained by using a structured questionnaire.A valid food frequency questionnaire(FFQ)was used to assess dietary intakes of the subjects during the last three months before delivery.Four diet indices such as Diet quality index-international(DQI-I),Dietary Approaches to Stop Hypertension(DASH),Alternate Healthy Eating Index(AHEI-2010)and Alternate Mediterranean Diet Score(aMed)were calculated based on the dietary intake information converted from FFQs according to the Chinese Food Composition Tables.Moreover,factor analysis was used to construct the dietary patterns according to the dietary survey data of this population.SPSS 25.0 was used to establish a database and conduct statistical analysis.Statistical significance was inferred from P values below 0.05.The differences between the cases and controls were compared by using paired t-tests or Wilcoxon sighed ranks test for continuous variables and paired chi-square tests for categorical variables.The scores of four diet indices and dietary patterns were all divided into four ascending categories based on the quartile cut-offs.Odds ratio(OR)and 95%confidence interval(CI)for PE were obtained by using univariate and multivariate conditional logistic regression analysis.Results1.There was no significant difference between the two groups in mean age and gestational age(P>0.05).Fifty-nine of pregnant women in each group had GDM.Compared with the control group,the cases with PE had higher SBP,DBP,weight before delivery and pre-pregnancy BMI,and lower height.The patients with PE were more likely to have a lower education level,a family history of hypertension and to be nulliparous than the controls(P<0.05).2.Compared with the control group,the cases with PE had significantly lower intakes of total dietary energy,most food groups and nutrients,especially in potato,legumes,vegetables,fruits,meat,egg,dairy products,proteins,and various vitamins and minerals(P<0.05).3.In the analysis of the four dietary indices,the results showed that except for aMED,scores of DQI-I,DASH and AHEI-2010 were significantly lower than those of the control group(P<0.05).The results of conditional logistic regression showed that participants in the highest quartile of the DQI-I and DASH scores were less likely to have PE after adjusting for major confounders.Compared with those in the lowest quartile,the OR(95%CI)of PE were 0.73(0.56,0.95)and 0.74(0.57,0.97),respectively.And there were negative associations between DQI-I and DASH scores and the odds of PE(Ptrend<0.05).However,there was no statistically significant relationship between AHEI-2010 and aMED scores and PE after adjusting for major confounders(P>0.05).The results of conditional logistic regression for patients without GDM were consistent with the results of the whole population,which verified the stability of our results.4.In this study,four major dietary patterns were obtained by factor analysis such as the "healthy dietary pattern",the "high meat pattern",the "fruit beverage pattern"and the "high grain pattern".The results showed that the odds of PE was reduced by 30%(OR=0.70,95%CI:0.51,0.94)and 37%(OR=0.63,95%CI:0.47,0.85)in the group with the highest score of the "healthy dietary pattern" and the "high meat pattern",respectively,compared with the group with the lowest score by multivariate conditional logistic regression analysis.And the higher the scores,the lower the odds of PE for pregnant women(Ptrend<0.05).However,the odds of PE was increased by 35%(OR=1.35,95%CI:1.00,1.82;Ptrend=0.050)in the group with the highest score in the "high grain pattern"compared with the group with the lowest score.The"fruit beverage pattern" was not found to be associated with the odds of PE.Conclusion1.Our findings suggest an inverse relationship between the scores of DQI-I and DASH diet indices and PE.2.Among the four dietary patterns obtained by factor analysis,the "healthy dietary pattern" and the "high meat pattern" may be two protective dietary patterns of PE;whereas the "high grain pattern" associate with the increased odds of PE.To prevent the occurrence of PE,pregnant women in central China are recommended to refer to the first two dietary patterns and to avoid the "high grain pattern" during pregnancy.