Developing Lifestyle Intervention Program Focusing On Dietary Improvement For Rural Women With A History Of GDM Based On TPB And Intervention Program Assessment

Background:Gestational diabetes mellitus（GDM）is a risk factor for diabetes mellitus type 2（T2DM）.Healthy lifestyle is a key strategy for women with a history of GDM to prevent T2DM.Currently,lifestyle interventions for women with previous GDM are mainly conducted in urban area.Since the women living in rural area are quite different at lifestyle,health literary and medical resources with the women living in urban area,thus,lifestyle interventions previously designed are not fully suitable for women living in rural area.Thus,developing lifestyle intervention specifically for women with previous GDM living in rural area is urgently needed.Objectives:（1）Describing dietary quality,anthropometric parameters and blood glucose of women with a history of GDM living in rural area via a cross-section study,to understand the lifestyle and health status of this group of people;（2）Developing lifestyle intervention program for women with a history of GDM living in rural area,to facilitate T2DM prevention;（3）Assessing the influence of lifestyle intervention program to women with a history of GDM living in rural area in terms of dietary quality,anthropometric parameters and blood glucose,via a randomized controlled study.Method:this project is conducted in three phases.The first phase:analyzing lifestyle status and influence factors among women with a GDM history in rural area in Hunan province.A cross-sectional study was implemented.Women with a history of GDM living at two rural county/district in Hunan province were enrolled via cluster random sampling between September to November 2017.We collected information by questionnaires filling,anthropometric and blood glucose testing.The questionnaires included basic and socioeconomic status questionnaire,international physical activity questionnaires short form（IPAQ-SF）,intention to eat low glycemic index foods questionnaire（IELQ）and 3×24h dietary recall.The dietary behavior,dietary pattern and dietary quality were analyzed on the basis of 3×24h dietary recall.Anthropometric parameters included height,weight,waist circumference,body fat percentage,moreover,body mass index（BMI）was calculated.Blood glucose parameters included fasting plasma glucose（FBG）and 2-hour glucose level after oral glucose tolerance test（OGTT）.The status of dietary behavior,dietary quality,anthropometric parameters and blood glucose was described via descriptive statistics,and their influence factors were tested by mono-and multi-variate regression models.The second phase:developing lifestyle intervention focusing on dietary improvement for women with a history of GDM in rural area.Based on the work of first phase,a taskforce for lifestyle intervention program development was formed,and cross-discipline experts were invited to join in it.Lifestyle intervention program for women with a history of GDM living in rural area was formulated on the basis of theory of planned behavior（TPB）.By referring to ADAPT-ITT model,The taskforce formulated the intervention program through 6 steps-applying theoretic framework,determining intervention module,assessing intervention requirement,drafting intervention program,conducting expert inquiry and finalizing intervention program.And a pilot was conducted to evaluate the plausibility of intervention program.The third phase:assessing the lifestyle intervention program.Conducting cluster randomized controlled study among women with a history of GDM living in rural area who participated in the cross-sectional study at first phase.Women in the intervention group join in a 6-month lifestyle intervention program at the basis of usual medical care,and women in the control group received usual medical care.The dietary quality,anthropometric parameters and blood glucose were followed at the time points of 6^th month（intervention completion）and 18^th month（1 year after intervention completion）.The primary endpoints included total score of Chinese health eating index（CHEI）,percentage of women who reached5 or more scores at minimum dietary diversity for women scale（MDD-W）,weight,BMI,waist circumference,prevalence of women with obesity or overweight,FBG,OGTT2H.The secondary endpoints included percentage of adequate food intake,prevalence of abnormal blood glucose or diabetes,CIELQ and low physical activity.Independent-sample T test,Mann-Whitney test,chi-square test was applied to compare dietary quality,anthropometric parameters and blood glucose between two groups at 6^thmonth and 18^th month.The influence of intervention to dietary quality,anthropometric parameters and blood glucose was assessed via generalized linear mixed model（GLMM）,furthermore,the mediating effect of dietary quality between lifestyle intervention and blood glucose was analyzed via PROCESS program.Results:The first phase-cross sectional study（1）Totally 404 women with a history of GDM living in rural area were enrolled in the cross-sectional study.The average age of 404 women was31.3,and 45.7%of them were from minority ethnicity groups.（2）The dietary intake of women with a history of GDM living in rural area was unbalanced.Many food groups（e.g.,whole grain and mixed beans,tubers,vegetables,fruits）were consumed insufficiently for more than 70%of them,and intake of poultry and red meat was excessive for more than60%of them.Total fat and saturated fat were consumed excessively for more than 75%of the women,while 40%to 96%of them consumed micronutrients（e.g.,calcium,iron,selenium,vitamin A,vitamin B1,vitamin B2）insufficiently.（3）The dietary quality for women with a history of GDM living in rural area was low.The average Chinese healthy eating index（CHEI）was 54.9,the median score of five food items,namely whole grain and mixed beans,tubers,diary,seeds and nuts,poultry was zero.Only 64.6%of the women reached 5 or more scores at minimum dietary diversity for women（MDD-W）scale.（4）Score of Chinese intention to eat low GI foods questionnaire（CIELQ）was low among women with a history of GDM living in rural area,with median level of 106.Only 17.8%of them knew glycemic index of foods before our study.（5）In this cross-sectional study,13.9%of the women were with obesity,31.9%of them were overweight.54.5%of them had waist circumference over 80cm,and 39.1%of them had a body fat percentage more than 35%.The prevalence of abnormal blood glucose（impaired fasting glucose or impaired glucose tolerance）was 16.6%The second phase-lifestyle intervention program developingA 6-month lifestyle intervention program was formulated by applying theoretic framework,determining intervention module,assessing intervention requirement,drafting intervention program,conducting expert inquiry and finalizing intervention program.Focusing on die,the lifestyle intervention program aims to improve dietary quality and lifestyle behavior,and control prevalence of overweight/obesity and blood glucose.There are two phases in the intervention program.In the initial 3-month intensive intervention phase,6 face-to-face group session were conducted,with the theme of improving T2DM disease knowledge,improving dietary habit,improving physical activity habit,facilitating pressure management,calling for family support and reinforcing lifestyle change.Follow-up calls（5 times）was conducted after the group session.In the second consolidating phase,three follow-up call were conducted at a frequency of once every month.The third phase-lifestyle intervention assessment（1）All of the 404 women who participated in the cross-sectional study signed informed consent and joined in a cluster randomized controlled study.There were 287 women completed the study.（2）At the time point of 6^th month（intervention completion）,the intake of whole grain and mixed beans,tubers,vegetables,dark vegetables,diary,seeds and nuts,fish and seafood,poultry and oil in the intervention group was higher than that in the control group,while intervention group consumed less total grains and red meat（P<0.05）;the rate of adequate intake of dark vegetables,fish and seafood,and oil of intervention group was higher in intervention group than that in the control group,while the rate of adequate intake of total grain was lower in intervention group（P<0.05）.At the time point of 18^th month（1 year after intervention completion）,the intake of whole grain,whole grain and mixed beans,and red meat was lower in the intervention group,and the soybean was consumed more in the intervention group（P<0.05）;the rate of adequate intake of total grain of intervention group was lower（P<0.05）.（3）The CHEI total score of intervention group was higher than that of control group at 6^th month（68.6 vs 61.4）and 18^th month（62.2 vs 58.8）（P<0.05）.More women in the intervention group scored 5 or more at MDD-W scale at 18^th month（90.6%vs 81.2%,P=0.023）.（4）The FBG of intervention group was lower than that in control group at18^th month（4.94 vs 5.13,P=0.045）.The prevalence of abnormal blood glucose and diabetes was similar between two groups at 6^th month and 18^thmonth（P>0.05）.The prevalence of overweight and obesity in the intervention group was lower than that in the control group at 6^th month（28.5%vs 39.9%,P=0.026）.（5）GLMM model implied that lifestyle intervention exerted impact to CHEI（F=17.014,P=0.000）and FBG（F=7.089,P=0.026）.PROCESS program revealed partial mediating effect of CHEI between lifestyle intervention and FBG（Effect=-0.488,Boot LLCI=-0.788,Boot ULCI=-0.231）,the mediating effect took up 28.2%in total effect.Conclusion:（1）Substantial proportion of women with a history of GDM in rural area live with unbalanced dietary habits and low dietary quality.Nearly half of the women are overweight or with obesity,and nearly one fifth of them have abnormal blood glucose.Thus,a lifestyle intervention focusing on diet is urgently needed.（2）A 6-month lifestyle intervention program focusing on diet has been formulated for women with a history of GDM in rural area.Local medical staff conducts 6 face-to-face group sessions,and 5 follow-up calls in the first 3-month intensive intervention phase.And three follow-up calls are conducted at 3-month consolidating phase.This intervention program is specifically constructed for women with a history of GDM living in rural area on the basis of cross-sectional study and TPB.And the feasibility and plausibility of intervention program is secured by involving multi-discipline experts and local medical staff.（3）The cluster randomized controlled trial reveals that lifestyle intervention focusing on diet can improve the dietary quality for women with a history of GDM living in rural area（CHEI:68.6 vs 61.4,P=0.000）,and reduce the prevalence of overweight and obesity（28.5%vs 39.9%,P=0.026）.After 1year of intervention completion,its influence to dietary quality（CHEI:62.2 vs 58.8,P=0.001）sustains,moreover,the FBG of intervention group is lowered than that in control group（4.94 vs 5.13,P=0.04）.Mediating effect analysis implies that lifestyle intervention helps blood glucose control via improving dietary quality.The lifestyle intervention program focusing on diet developed is of practical significance for improving the health of women with a history of GDM living in rural area.