Received 11 February 2016; accepted 4 April 2016; published 7 April 2016
The prevalence of diabetes and obesity has reached epidemic proportionsand became major public health con- cerns worldwide. In Malaysia, according to 3rd National Health Morbidity Survey (NHMS III) study, the inci- dence of Type 2 Diabetes Mellitus (T2DM) and obesity are increasing in all age groups, all racial groups among both sexes  . Globally, the incidence of Gestational Diabetes Mellitus (GDM) is rising, paralleling the rises in T2DM and obesity prevalence  . The prevalence of GDM among adults reproductive age above 30 years in Malaysia had arisen from 8.3% in 1996 to 14.9% in 2006  . Scientific evidence has shown that GDM women are at increased risk of developing obesity and T2DM  . Hence, it is crucial to identify women with GDM or those at risk for GDM as a target group to implement strategies to delay or prevent T2DM onset. Systematic review study has shown that up to 50% of women who have had GDM will develop diabetes in subsequent pregnancy  . It has been projected that, women with a history of GDM are increased markedly in the first 5 years after delivery to develop T2DM  .
GDM is defined as any degree of glucose intolerance with onset or first recognition during pregnancy and it is associated with short and long term morbidity in both mother and child  . Adverse infant outcomes include macrosomia, hypocalcemia, erythemia, hypoglycemia, jaundice, and birth trauma  . Later in life, these children are more likely to become obese, have an abnormal glucose tolerance, and develop diabetes in early adulthood  . GDM increases the mother’s risk of hypertensive disorders during pregnancy, Caesarean delivery  and metabolic syndrome later in life  .
Maternal and infant morbidity in the presence of GDM are highly associated with modifiable factor such as unhealthy lifestyle  . Exercise during confinement halved the risk of GDM among obese women  . Pregnant women who are physically active within the first 20 weeks in their pregnancy were noticed unlikely to develop GDM by halved  . Solomon et al. reported that women who engaged in vigorous activity or brisk walking at pre pregnancy stage were less likely to develop GDM  . Many studies have demonstrated that mo- derate intensity of physical activity during pregnancy with recommended duration of 30 minutes or more on most days of the week  , is safe  and associated with good pregnancy outcome  . While, not physically active pregnant women were highly associated with GDM risk  . Evidences have suggested that both diet and physical activity altered the increase in insulin resistance especially during mid and late pregnancy  . There- fore, behavioural interventions were important to promote pregnant women practicing healthy diet in order to prevent subsequent obesity and GDM  . Saldana et al. found that there is significant asssociation between high saturated fat diet intake and glucose intolerance in pregnant women  . While taking high fibre diet will have protective effect in preventing GDM incidence   . Physical activity and appropriate diet may prevent excessive gestational weight gain  and thus is crucial for dissevering the bound involving GDM, obesity and diabetes  . Three previous studies aimed at preventing excessive gestational weight gain  -  showed excessive gestational weight gain was prevented among the low-income or subgroups of normal-weight pregnant women.The information on weight gain in pregnancy as recommended by Institute of Medicine (IOM) in 2009, has been used in antenatal care monitoring  .
Lifestyle interventions have been proven to reduce diabetes risk    . Therefore, identifying women at high risk of GDM will provide an excellent opportunity for proper intensive life style intervention  . The objective of this study was to assess the effectiveness of intensive and structured program on lifestyle counselling based on 3 components; physical activity, appropriate diet, and monitoring on gestational weight gain as recom- mended by IOM through intergration in an antenatal clinic follow up. The main hypothesis of this study stated: there is a significant difference between intervention and control groups in incidence of GDM, excessive gesta- tional weight gain, comply to diet intake and physical activity as recommended.
2.1. Setting and Study Design
This study was approved by Ethical Committee University Kebangsaan Malaysia Medical Centre and National Medical Research Review and was funded through a grant from a Universiti Kebangsaan Malaysia medical Centre (UKMMC) funding. This is a Quasi-Experimental study among high risk GDM antenatal mothers at two selected intervention clinics using intensified lifestyle counseling (ILC) and two control clinics using routine standard practice (RC). The study was conducted in Negeri Sembilan, Malaysia as it has shown increase in Diabetes melitus reported by National Health Morbidity Survey over a decade in 2011  . All clinics are situated in Seremban district of Negeri Sembilan were chosen purposively based on increasing incidence of GDM and highest number of antenatal cases’ attendance per annum. The recruitment of subjects started from September 2013 until November 2014. In the ILC, the subjects received intensive lifestyle counseling delivered by the nutritionist while in the RC the subjects received routine standard practice counseling. Five sessions of counseling were conducted during antenatal visits starting from 12 - 14 weeks gestation until 37 - 39 weeks gestation. The counseling were held in the health education room.
2.2. Sampling Method
The subjects selected were all pregnant women with the presence of at least two risk factors for GDM (BMI > 27 kg/m2, previous macrosomic baby weighing 4 kg or above, previous GDM, first-degree relative with diabetes, glycosuria at the first prenatal visit and maternal age above 25 years old). The screening method was done using the 75 g Oral Glucose Tolerance Test (OGTT) and was performed at 12 weeks of gestation amongst these high risk GDM mothers. The OGTT results is normal if the fasting plasma glucose ≤5.6 mmol/L and 2-hour plasma glucose ≤7.8 mmol/L and any reading above this value will be diagnosed as GDM as per Ministry of Health, Malaysia’s Guidelines for GDM. The inclusion criteria for inception recruitment of both groups were 1) normal OGTT, 2) antenatal care established at <12 weeks period of amenorrhea (POA), 3) able to read and write in Malay or English language 4)willing to participate voluntarily with written consentand d) Malaysian nationality. Exclusion criteria were; 1) twin/multiton pregnancy 2) pre-existing Diabetes Mellitus 3) patients whom participating in another recent study, 4) subjects with current obstetric complications (yellow and red colour coded maternity card), and e) suffering from any other medical illness.
Each of eligible subjects in both intervention and control clinic were explained about the study in brief by the research assistant (nurse) during recruitment phase (first antenatal care visit). Figure 1 shows that after obtaining informed consent from these subjects, the control groupreceived RC in the second antenatal care visit, including an initial physical examination and OGTT. During subsequent antenatal routine visits for control group, the RC was delivered focusing on diet and exercise during pregnancy as in Standard Operating Procedure for Pre-Diabetes by Division of Dietitian, Ministry of Health, Malaysia (2011). At each routine antenatal visit the weight was measured using a Seca 700 mechanical beam medical scale and recorded in the antenatal home based card.
The intervention group underwent a complete history and physical examination (at first antenatal care visit) with specific attention paid to pre-pregnancy weight, current weight, height and body masss index (BMI). At the second visit, and subsequent visits (all five sessions) the intervention group met with a nutritionist to receive ILC that included information on three main component (pregnancy healthy diet, appropriate physical activity choices and appropriate weight gain during pregnancy using the IOM guidelines). The content of diet advice follows Malaysian Dietary Guidelines, Recommended Nutrititional Intake for Malaysia in 2005  . The five sessions of intensive lifestyle counselling sessions were planned at period of gestation 12 - 14 weeks, 16 - 18 weeks, 22 - 24 weeks, 26 - 28 weeks and 32 - 34 weeks. At the beginning of firstcounselling session, the base- line questionnaire which covered and assessed the sociodemographic factors, reproductive factors, current die- tary habits Food Frequency Questionnaire (FFQ) and Pregnancy Physical ActivityQuestionnaire (PPAQ) of the subjects. The intervention group received counselling on 3 components; dietary intake, physical activity and recommendation of weight gain. After comparing the personal habits to the recommendations, the nutritionist assessed and planned the need for dietary changes, modify lifestyle based on identified barriers. Each subjects received a structured take home leaflet on physical activity and healthy diet during pregnancy at each visit.
The sample size is calculated based on effect size of recent study by Luotto et al.  that showed 30% - 35% of pregnant women in control group gaining weight within IOM guidelines and 25% - 55% of pregnant women in the intervention group gaining weight within the IOM guidelines. Using Fleiss JL formula  , 90% power and an alpha of 0.05, the required sample calculated was 132 subjects in each arm. However we added another 20% to encounter drop out rate, hence the sample needed for each arm was 160 subjects. The primary outcome was the incidence of GDM. The secondary outcomes were proportion of subjects gaining weight within the BMI specific recommendations by IOM 2009)  , proportion of subject comply to the Recommended Nutritional Intake (RNI)  and physical activity. Body weight and pregnancy data such as incidence of GDM were obtained from the home based card. Body weight was measured in light clothing and without shoes at every maternity care visit using Seca beam scale. While, the height was measured with standardised stadiometer
Figure 1. Study flow chart.
during the first visit only. The scales were calibrated through out the study. Baseline information on age, weight, height, BMI, education level and occupation were collected in both groups. These demographic characteristics were described using per cents, frequencies, means and standard deviations. Potential differences between the two groups (intervention and control) were analysed using Chi square tests and t-tests. A p value of less than 0.05 was used to define statistical significance in all cases. All analyses were performed using Statistical Package for the Social Sciences 21.
2.3. Intervention Package
For diet component of counselling, the food calory intake was calculated based on RNI  and the food pyramid for Malaysian. According to pregnancy stages, the goals component of the diet used in the intervention group as follow; total energy intake within RNI, carbohydrate 50 - 55 energy per cent (E%), fat < 30 E% and protein 15 - 20 E%. The food parameter was measured twice, at the baseline before intervention and after completion of five sessions of intensive lifestyle counseling. The dietary intake data that obtained from the respondents’ FFQ were calculated manually by the nutritionist using standard manual food atlas for Malaysian. Women who were compliance to the dietary advice were defined as those who achieved at least two out of four goals. Women were encouraged to eat a diet rich in vegetables and fruits, and to use low-fat dairy products, low-fat meat, vegetable oils and wholegrain products.
2.3.2. Physical Activity
The respondents’ physical activities data that obtained from the PPAQ was based on the amount of their time spent in 32 activities including household/caregiving, occupational, sports/exercise, and inactivity during the current trimester. The duration of time spent in each activity (moderate intensity) is multiplied by its intensity to arrive at a measure of average weekly energy expenditure (MET-h・week-1) attributable to each activity. Those with sedentary lifestyle were advised to have three times a week of continuous exercise for 15 minutes  and increasing gradually to four times a week for 30 minute sessions  . Recommendable types of exercise were brisk walking, swimming, Nordic walking, and antenatal exercise  . Compliance to recommended moderate intensity physical activity was those subjects who achieved at least 600 Met/min per week.
2.3.3. Gestational Weight Gain
The subjects were taught to monitor body weight gain at each antenatal visits as recorded in the antenatal home based card. The accepted gestational weight gain as recommended (stated in the antenatal home base card) is 0.5 kg per month for the first 5 months of pregnancy and 0.5 kg per week for remaining pregnancy period. Adherance to IOM guidelines were those subjects who complied to the recommended total gestational weight gain  .
The nutritionists were trained about the counselling method which is based on transtheoretical model (TTM) by Prochaska et al.  . For each specific changes in subjects behaviour towards dietary intake and physical activity during pregnancy were mapped on TTM stages (pre-contemplation, contemplation, preparation, action and maintainance). Those who were dropped out and missed the counselling appointment, home visit will be made for the counselling. In this study, there was low dropped out rate.
There were 320 eligible women (160 subjects in each arm)from selected intervention and control clinics. In intervention clinics, 160 eligible women were recruited, of these consented subjects, 12 women were excluded and there were only 148 (93%) women were included in this intervention group. All subjects in intervention group were involved in physical activity and dietary counselling sessions. However, of these 160 subjects recruited in control clinics, 10 women were excluded and it is estimated that 150 subjects (94%) in the control group participated in this study. Therefore, a total of 298 women in both intervention and control group completed the study and were available for analysis which showed that there were no statistically significant difference seen in baseline demographic composition and clinical examinations between the intervention and control group as shown in Table 1.
The results as in Table 2 showed that there is significant association between GDM incidence and study groups. Intervention group that received ILC had lower incidence of GDM, 9 subjects (6.1%) as compared to control group that received RC, 25 subjects(16.7%), (χ2 = 0.80, p = 0.004). Further analysis with simple logistic regression analysis showed the predictors of GDM. The results presented that intervention group showed 3 times protected from the risk of GDM incidence (crude OR: 0.32, 95%CI: 0.17 - 0.72, p = 0.006) as compared to control group, glycosuria showed 5 times risk of GDM (crude OR: 4.99, 95%CI: 2.22 - 11.24, p < 0.01), while previous GDM showed 4 times risk of GDM in current pregnancies (crude OR: 3.88, 95%CI: 1.86 - 8.10, p < 0.01). However, after controlling covariates and confounders, it was found that control group persistently showed protective effect, 4 times protected from the risk of GDM incidence compared to intervention group (adjusted odds 0.25, 95%CI: 0.18 - 0.53, p = 0.003). It means that the intervention has reduced the GDM incidence as four times.
The secondary study outcomesshowed that the intervention group gained significantly lesser total weight gain (11.39 ± 2.52) compared to control group (12.69 ± 2.88), p < 0.01. The compliance rate of adherence to IOM guidelines was found higher in the intervention group. The predictor for recommended total weight gain during pregnancy were determined by factors adherence to IOM. Analysis using simple logistic regression found significant finding on pre-pregnancy BMI. Among the BMI classification, women with normal weight (BMI < 25) were more likely to adhere to the IOM guidelines. For example among all respondents in intervention group, 73.4% normal weight women were adherence to IOM guidelines as compared to overweight women (17.4%) and obese women (9.2%), p < 0.01. While among all women in control group, 80.3% were normal weight women who adherence to IOM guidelines as compared to overweight women (17.4%) and obese women (9.2%),
Table 1. Demographic and clinical characteristics of women in intervention and control group.
* = t test; # = Chi square; # # = Fisher; BMI = Body Mass Index; FBS = Fasting Blood Sugar; 2HPG = 2 Hour Plasma Glucose; wks POA = Weeks Period of Amenorrhhea.
Table 2. Factors in determining GDM risk (bivariate and multivariate logistic regression).
p < 0.01 (Table 3).
Based on ANOVA Two-Way Repeated Measures analysis as in Table 4, explained that there is no difference in physical activity (moderate intensity) mean score at first trimester (baseline) between intervention group (602.46 Met/min, sd = 369.46) and control group (604.52 Met/min, sd = 251.20). However there is difference in physical activity mean score between these two groups at second trimester intervention group (678.86 Met/min, sd = 306.38) and control group (605.35 Met/min, sd = 251.19). At the third trimester, physical activity mean score is increased in intervention group (699.60 Met/min, sd = 192.37) but reduced in the control group (504.22 Met/min, sd = 188.75). There is a significant difference in total mean score of physical activity between intervention group (660.30, sd = 289.40) and control group (571.36, sd = 230.38); F (1, 296) = 10.418, p = 0.001. ANOVA test (between subject found that study groups factor has significant main effect on physical activity level, F (1, 296) = 10.4, p < 0.01, and the effect size is moderate (eta square value = 0.035). While, ANOVA test (within subject) also showed that there is significant main effect of time factor on physical activity level, F(1.15, 340.89) = 33.19, p < 0.01, and the effect size was small (eta squared = 0.023). However, there is moderate interaction effect of two factors (time and study group) on physical activity level (eta squared = 0.101).
Chi square test revealed that there is significant association between study groups and compliance to dietary intake recommendations (at least 2 out of 4 recommendations from RNI Malaysia guidelines). There were 75 respondents (50.7%) in intervention groups are comply to diet recommendation as compared to 29 respondents (16.7%) in control group, (χ2 = 32.210, p < 0.01). T test showed (Table 5) that there is significant difference in total calories intake which is more in the control group 2290.70 ± 183.03 kcal as compared to intervention group (2221.14 ± 227.81) kcal with t = 2.555; p = 0.01 There is also higher intake of diet containing fat amongst control group 30.67 ± 3.70 E% compared to control group 28.65 ± 4.12 E%, t = 4.445; p < 0.01. However, there
Table 3. Gestational weight gain (secondary outcome) and pre-pregnancy body mass index adherent to institute of medicine guidelines between study groups (post-intervention).
GWG = Gestational Weight Gain; BMI = Body Mass Index; IOM = Institute of Medicine, America; # = Chi square ;* = t test; 0 = Control group; + = Intervention group.
Table 4. ANOVA-2 way repeated measures analysis on physical activity (moderate intensity) between intervention and control group (post-intervention).
sd = standard deviation.
Table 5. Comparison of dietary intake between intervention and control group (post-intervention).
t = t test; sd = standard deviation; E% = Energy percent.
is no significance difference in carbohydrate and protein intake between these two groups.
Our study showed that there was less incidence of GDM in intervention group (6.1%) as compared to control group (16.7%). This finding similar with the study done by Hu et al. which randomized 404 participants diagnosed with GDM from 2005 to 2009 to either a lifestyle intervention or a control group  and the results indicated that women in the intervention group had a greater reduction in plasma insulin levels (11.8 ± 27.4 pmol/l) as compared to those in the control arm (3.2 ± 31.2 pmol/l, p = 0.004). While a study by Shyam et al. observed a positive impact of the intervention on fasting glucose levels by among 77 Asian women who had been diagnosed with GDM using low glycemic index dietary intervention  . Their study showed that 6 months of follow-up, the intervention group had significantly decreases in 2-h post-prandial blood glucose after a 75-g oral glucose tolerance test (2.8 mmol/l) as compared to the control arm (2.0 mmol/l), p = 0.025  .
Intensive lifestyle counselling in our study has significantly lesser total gestational weight gain in intervention as compared to control groups. The intervention showed a significant difference in the rate of adherence to IOM guidelines. Our study has similar findings with intervention study done by Asbee et al.  . That study found that higher pre-pregnancy BMI would have less adherences to IOM guidelines and risk for excessive gestational weight gain  . Our study supported earlier findings found by Polley et al. & Kinnunen et al. who gave struc- tured counselling and education about healthy eating, appropriate exercise and proper weight gain   . Their study showed that there was a reduction of percentage of women who gained weight more than the IOM recommendations in the intervention group compared to controls. Another study by Olson et al. & Mamun et al. found that an intervention by health education program delivered by healthcare provider via mail had signifi- cantly reduced excessive weight gain amongst low income subgroup   .
Our lifestyle intervention has significantly reduced the total fat intake and calories intake among respondents in intervention group as compared to control group. Our study result has similar findings with four trials done recently that examined the impact of the lifestyle intervention on diet by Hu Gang et al. in 2012; Shyam et al. in 2013; Ferrara et al. in 2011 and Reinhardt et al. in 2012 which observed a statistically significant beneficial effect on one or more dietary components     . For example, in the study by Ferrara et al., the result showed a significant mean difference in fat intake of 3.55% between the lifestyle arm and the control arm (p = 0.002)  . Hu et al. stated in their study that the lifestyle intervention group had 77.1% decrease in energy from fat as compared to a 68.9% decrease in the control group (p = 0.064)  . Reinhardt et al. in their 6-month pilot study among Australian women found a change in total fat between the arms of 19 g/day (95% CI: 37, 1)  . A positive impact of the lifestyle intervention on dietary fiber intake was also detected by Hu et al. and Shyam et al. but not in our study   . There was significantly positive impact of physical activity among respondents in intervention group as compared to control group in our study. Our study finding was similar with those three studies by Hu Gang et al. in 2012; Reinhardt et al. in 2012 & Ratner et al. in 2008, which examined the impact of lifestyle intervention on physical activity among women diagnosed with GDM that observed a statistically significant impact on one or more measures of activity    . For example, in the trial by Reinhardt et al., the intervention group increased leisure physical activity compared to the control group by 11 min per day (95% CI: 1, 22)  . Hu et al. found a similar beneficial impact on leisure-time physical activity, with an increase of 59.4% in the intervention group as compared to a 26.9% increase in the control group (p < 0.001)  . A trial by Ratner et al. showed an increase of approximately 1.5 hours per week in moderate-inten- sity physical activity after 1 year among respondents in the intervention group  .
The strength of the study is mainly of its design, a quasi-experimental study. The questionnaires used were validated food frequency and physical activity questionnaire for pregnancy woman. This is a comprehensive intervention program consists of lifestyle counseling, health education, discussion and motivation support de- livered by expert health personnel, nutritionists. Mode of delivering counseling intervention were through power point presentation, take home leaflet, diet and physical activity diary discussions. The intervention took place at existing health education room. This interventional study has low dropped out rate, and those who werenot able to attend for the counseling, a new appointment for counseling will be given through phone call or home visit. Our study has several limitations. Hawthorne effect may have occured, the repondents who involved in the intervention were counseled regarding recommended dietary intake, physical activity and weight gain during pregnancy would have more likely to give specific attention on this factors and would modify their behaviours accordingly. However there were few subjects who were not ready to change their risky behaviour in the beginning of intervention have had complicated the study. While information on pre-pregnancy body weight that was self reported will prone causing self-reported bias. Content bias would have occured too because we were unable to control content of the counseling delivered by the nutritionist to the subjects during each maternity visits although using the same intervention module.
An organized, consistent using a structured program tailored to society needs on lifestyle counselling able to reduce incidence of GDM through modifying potential risk behaviour. Therefore, it is important to counsel all women at risk of GDM during antenatal visit at primary health care on the importance of diet, physical activity and weight management. Concerted effort to organize dedicated team, implementing intensified lifestyle coun- seling program and sustainably run it can reduce the potential hazardous to mother and baby outcome. It is re- commended pre pregnancy care clinic to do proper screening in identifying risk of pre pregnancy BMI and continue proper antenatal monitoring for good gestational weight gain in order to prevent GDM. The intensive lifestyle counseling package have shown effectiveness in prevention of GDM among high risk group. Therefore, this package should be disseminated to all health care provider in all healthcare centre.
The authors thank the Ethical Committee Universiti Kebangsaan Malaysia Medical Centre for funding this study. We thanks the staffs from District Health Office Seremban for technical assistance during data collection, the Medical Officer of Health District Seremban and the Nutritionist for helping us in intervention package assessment.
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