Judith G. M. Jelsma

DALI: Vitamin D and lifestyle intervention for gestational diabetes mellitus (GDM) prevention: an European multicentre, randomised trial - study protocol

BackgroundGestational diabetes mellitus (GDM) is an increasing problem world-wide. Lifestyle interventions and/or vitamin D supplementation might help prevent GDM in some women.Methods/designPregnant women at risk of GDM (BMI≥29 (kg/m2)) from 9 European countries will be invited to participate and consent obtained before 19+6 weeks of gestation. After giving informed consent, women without GDM will be included (based on IADPSG criteria: fasting glucose<5.1mmol; 1 hour glucose <10.0 mmol; 2 hour glucose <8.5 mmol) and randomized to one of the 8 intervention arms using a 2×(2×2) factorial design: (1) healthy eating (HE), 2) physical activity (PA), 3) HE+PA, 4) control, 5) HE+PA+vitamin D, 6) HE+PA+placebo, 7) vitamin D alone, 8) placebo alone), pre-stratified for each site. In total, 880 women will be included with 110 women allocated to each arm. Between entry and 35 weeks of gestation, women allocated to a lifestyle intervention will receive 5 face-to-face, and 4 telephone coaching sessions, based on the principles of motivational interviewing. The lifestyle intervention includes a discussion about the risks of GDM, a weight gain target <5kg and either 7 healthy eating ‘messages’ and/or 5 physical activity ‘messages’ depending on randomization. Fidelity is monitored by the use of a personal digital assistance (PDA) system. Participants randomized to the vitamin D intervention receive either 1600 IU vitamin D or placebo for daily intake until delivery. Data is collected at baseline measurement, at 24–28 weeks, 35–37 weeks of gestation and after delivery. Primary outcome measures are gestational weight gain, fasting glucose and insulin sensitivity, with a range of obstetric secondary outcome measures including birth weight.DiscussionDALI is a unique Europe-wide randomised controlled trial, which will gain insight into preventive measures against the development of GDM in overweight and obese women.Trial registrationISRCTN70595832

Effect of physical activity and/or healthy eating on GDM risk: The DALI Lifestyle Study

Context Lifestyle approaches for preventing gestational diabetes mellitus (GDM) have produced mixed results. Objective The aim of the present study was to compare the effectiveness of 3 lifestyle interventions [healthy eating (HE), physical activity (PA), and both HE and PA (HE+PA)] with usual care (UC) in reducing GDM risk. Design The present study was a multicenter randomized controlled trial conducted from 2012 to 2014 [the DALI (vitamin D and lifestyle intervention for GDM prevention) lifestyle study]. Setting The study occurred at antenatal clinics across 11 centers in 9 European countries. Patients Consecutive pregnant women at <20 weeks of gestation with a body mass index (BMI) of ≥29 kg/m2 and without GDM using the International Association of Diabetes and Pregnancy Study Group criteria (n = 436). For the intervention, women were randomized, stratified by site, to UC, HE, PA, or HE+PA. The women received 5 face-to-face and ≤4 telephone coaching sessions using the principles of motivational interviewing. A gestational weight gain (GWG) <5 kg was targeted. The coaches received standardized training and an intervention toolkit tailored to their culture and language. Main Outcome Measures The endpoints were the GWG at 35 to 37 weeks and the fasting glucose and insulin sensitivity [homeostasis model assessment insulin resistance (HOMA-IR)] at 24 to 28 weeks. Results We randomized 108 women to HE+PA, 113 to HE, 110 to PA, and 105 to UC. In the HE+PA group, but not HE or PA alone, women achieved substantially less GWG than did the controls (UC) by 35 to 37 weeks (-2.02; 95% confidence interval, -3.58 to -0.46 kg). Despite this reduction, no improvements were seen in fasting or postload glucose levels, insulin concentrations, or HOMA-IR. The birthweights and large and small for gestational age rates were similar. Conclusions The combined HE+PA intervention was able to limit GWG but did not reduce fasting glycemia. Thus, lifestyle changes alone are unlikely to prevent GDM among women with a BMI of ≥29 kg/m2.

IADPSG and WHO 2013 Gestational Diabetes Mellitus Criteria Identify Obese Women With Marked Insulin Resistance in Early Pregnancy

Implementation of the International Association of Diabetes and Pregnancy Study Groups (IADPSG) and the World Health Organization 2013 (WHO 2013) recommendations leads to an increased prevalence of gestational diabetes mellitus (GDM) due to more stringent criteria and early screening of women at high risk for diabetes in pregnancy (DIP) (1,2). IADPSG members now recommend that their GDM criteria should not be used in early pregnancy but have not provided alternative criteria (3). We have compared the characteristics of overweight/obese women early in pregnancy, with and without GDM using the new criteria, to assess whether those testing positive are metabolically distinct. Pregnant women with a BMI ≥29.0 kg/m2 underwent a 75-g oral glucose tolerance test in early pregnancy as part of enrollment into the DALI (Vitamin D And Lifestyle Intervention for GDM prevention) pilot and lifestyle Pan-European multicenter trials (4). GDM and DIP were diagnosed using WHO 2013 criteria. A high rate of GDM (237/1,035 or 22.9%: DIP 0.5%; total hyperglycemia in early pregnancy 23.4%) was found at a …

How to Measure Motivational Interviewing Fidelity in Randomized Controlled Trials: Practical Recommendations

Many randomized controlled trials in which motivational interviewing (MI) is a key intervention make no provision for the assessment of treatment fidelity. This methodological shortcoming makes it impossible to distinguish between high- and low-quality MI interventions, and, consequently, to know whether MI provision has contributed to any intervention effects. This article makes some practical recommendations for the collection, selection, coding and reporting of MI fidelity data, as measured using the Motivational Interviewing Treatment Integrity Code. We hope that researchers will consider these recommendations and include MI fidelity measures in future studies.

Beliefs, Barriers, and Preferences of European Overweight Women to Adopt a Healthier Lifestyle in Pregnancy to Minimize Risk of Developing Gestational Diabetes Mellitus: An Explorative Study.

Introduction. We explored beliefs, perceived barriers, and preferences regarding lifestyle changes among overweight European pregnant women to help inform the development of future lifestyle interventions in the prevention of gestational diabetes mellitus. Methods. An explorative mixed methods, two-staged study was conducted to gather information from pregnant European women (BMI ≥ 25 kg/m2). In three European countries 21 interviews were conducted, followed by 71 questionnaires in six other European countries. Content analysis and descriptive and chi-square statistics were applied (p < 0.05). Results. Women preferred to obtain detailed information about their personal risk. The health of their baby was a major motivating factor. Perceived barriers for physical activity included pregnancy-specific issues such as tiredness and experiencing physical complaints. Insufficient time was a barrier more frequently reported by women with children. Abstaining from snacking was identified as a challenge for the majority of women, especially for those without children. Women preferred to obtain support from their partner, as well as health professionals and valued flexible lifestyle programs. Conclusions. Healthcare professionals need to inform overweight pregnant women about their personal risk, discuss lifestyle modification, and assist in weight management. Lifestyle programs should be tailored to the individual, taking into account barriers experienced by overweight first-time mothers and multipara women.

The intervention process in the European Fans in Training (EuroFIT) trial: a mixed method protocol for evaluation

BackgroundEuroFIT is a gender-sensitised, health and lifestyle program targeting physical activity, sedentary time and dietary behaviours in men. The delivery of the program in football clubs, led by the clubs’ community coaches, is designed to both attract and engage men in lifestyle change through an interest in football or loyalty to the club they support. The EuroFIT program will be evaluated in a multicentre pragmatic randomised controlled trial (RCT), for which ~1000 overweight men, aged 30–65 years, will be recruited in 15 top professional football clubs in the Netherlands, Norway, Portugal and the UK. The process evaluation is designed to investigate how implementation within the RCT is achieved in the various football clubs and countries and the processes through which EuroFIT affects outcomes.MethodsThis mixed methods evaluation is guided by the Medical Research Council (MRC) guidance for conducting process evaluations of complex interventions. Data will be collected in the intervention arm of the EuroFIT trial through: participant questionnaires (n = 500); attendance sheets and coach logs (n = 360); observations of sessions (n = 30); coach questionnaires (n = 30); usage logs from a novel device for self-monitoring physical activity and non-sedentary behaviour (SitFIT); an app-based game to promote social support for physical activity outside program sessions (MatchFIT); interviews with coaches (n = 15); football club representatives (n = 15); and focus groups with participants (n = 30). Written standard operating procedures are used to ensure quality and consistency in data collection and analysis across the participating countries. Data will be analysed thematically within datasets and overall synthesis of findings will address the processes through which the program is implemented in various countries and clubs and through which it affects outcomes, with careful attention to the context of the football club.DiscussionThe process evaluation will provide a comprehensive account of what was necessary to implement the EuroFIT program in professional football clubs within a trial setting and how outcomes were affected by the program. This will allow us to re-appraise the program’s conceptual base, optimise the program for post-trial implementation and roll out, and offer suggestions for the development and implementation of future initiatives to promote health and wellbeing through professional sports clubs.Trial RegistrationISRCTN81935608. Registered on 16 June 2015.

Risk factors for hyperglycemia in pregnancy in the DALI study differ by period of pregnancy and OGTT time point

OBJECTIVE Risk factors are widely used to identify women at risk for gestational diabetes mellitus (GDM) without clear distinction by pregnancy period or oral glucose tolerance test (OGTT) time points. We aimed to assess the clinical risk factors for Hyperglycemia in pregnancy (HiP) differentiating by these two aspects. DESIGN AND METHODS Nine hundred seventy-one overweight/obese pregnant women, enrolled in the DALI study for preventing GDM. OGTTs were performed at ≤19 + 6, 24-28 and 35-37 weeks (IADPSG/WHO2013 criteria). Women with GDM or overt diabetes at one time point did not proceed to further OGTTs. Potential independent variables included baseline maternal and current pregnancy characteristics. STATISTICAL ANALYSIS Multivariate logistic regression. RESULTS Clinical characteristics independently associated with GDM/overt diabetes were at ≤19 + 6 weeks, previous abnormal glucose tolerance (odds ratio (OR): 3.11; 95% CI: 1.41-6.85), previous GDM (OR: 2.22; 95% CI: 1.20-4.11), neck circumference (NC) (OR: 1.58; 95% CI: 1.06-2.36 for the upper tertile), resting heart rate (RHR, OR: 1.99; 95% CI: 1.31-3.00 for the upper tertile) and recruitment site; at 24-28 weeks, previous stillbirth (OR: 2.92; 95% CI: 1.18-7.22), RHR (OR: 3.32; 95% CI: 1.70-6.49 for the upper tertile) and recruitment site; at 35-37 weeks, maternal height (OR: 0.41; 95% CI: 0.20-0.87 for upper tertile). Clinical characteristics independently associated with GDM/overt diabetes differed by OGTT time point (e.g. at ≤19 + 6 weeks, NC was associated with abnormal fasting but not postchallenge glucose). CONCLUSION In this population, most clinical characteristics associated with GDM/overt diabetes were non-modifiable and differed by pregnancy period and OGTT time point. The identified risk factors can help define the target population for future intervention trials.

Changing psychosocial determinants of physical activity and diet in women with a history of gestational diabetes mellitus

To investigate how a behavioural lifestyle intervention influences psychosocial determinants of physical activity and dietary behaviours in a population at risk of type 2 diabetes (T2DM).

Re: Vitamin D and gestational diabetes mellitus: a systematic review based on data free of Hawthorne effect

Sir, We have read with utmost interest the recently published systematic review and meta-analysis of Zhang et al. on the relationship between vitamin D and gestational diabetes mellitus (GDM). The authors have performed a comprehensive review including 87 observational studies and 25 randomised controlled trials addressing the relationship between vitamin D and glucose homeostasis during pregnancy. The meta-analysis on observational studies confirmed that gravidas with low blood vitamin D have a higher risk of GDM (odds ratio 1.85) linked to higher fasting plasma glucose and Homeostatic Model Assessment of Insulin Resistance index (HOMA-IR). The crucial point in clinical practice is to know if vitamin D supplementation in addition to recommended dietary allowances is able to prevent GDM. The authors have performed a meta-analysis on randomised controlled trials showing that vitamin D supplementation elevates the concentrations of 25-OHD in blood, and reduces fasting insulin, fasting plasma glucose and HOMA-IR, as well as having favourable effects on glutathione, C-reactive protein and total and high-density lipoprotein cholesterol. However, after pooling the data from four trials including 968 pregnant women, it was unclear whether vitamin D supplementationwas effective inGDM prevention (relative risk 0.718, 95% CI 0.392–1.314, I = 0% [I is in fact 37]). The authors identified that omitting the study of Hossain et al. rendered the comparison significant (Table 1 in Zhang et al, P = 0.008). In the study of Hossain et al. the outcome reported was not incident GDM but an abnormal glucose challenge test. Although it is intriguing that the rate of abnormal glucose challenge tests was higher albeit not significantly in the intervention group, our point is that this study should not be pooled together with studies where the outcome is GDM. We have performed the meta-analysis of the remaining three studies including 793 pregnant women and the result is relative risk 0.53, 95% CI 0.33–0.85, I = 0%, P = 0.009 (Figure 1). Common features of these three studies are that the participants’ average vitamin D concentration at baseline was < 50 nmol/l and that vitamin D doses in the intervention arm were high ( 3500 iu/day, 5000 iu/ day, up to 3400 iu/day), including doses higher than the Institute of Medicine’s tolerable upper intake level. Hence, as to external validity, these results would only apply to pregnant women with low vitamin D receiving high daily doses of the vitamin. Furthermore, in one of the trials, women in the control arm did not receive any supplement. Notably, the magnitude of the risk of GDM with low vitamin D (odds ratio 1.85) and the protection afforded by supplementation (relative risk 0.53) are of a similar magnitude and opposite direction. On the basis of these additional considerations, we conclude that ‘highdose vitamin D supplementation during pregnancy halves the rate of GDM in pregnant women with baseline vitamin D for less than 50 nmol/l’.&