Research Article

Exploring the Advice and Rationale of Health Practitioners in Prescribing a Bedtime Snack for Gestational Diabetes

Francois ME^1,2, Desmares-Matters M¹, Kennedy M^1,3 and Roach LA^1,2

¹School of Medicine, University of Wollongong, Australia

²Illawarra Health and Medical Research Institute, Australia

³Illawarra Shoalhaven Local Health District, Australia

Submission: April 19, 2021;Published: May 18, 2021

*Corresponding author: Monique Francois, School of Medicine, University of Wollongong, Australia

How to cite this article:Francois M, Desmares Matters M, Kennedy M, Roach L. Exploring the Advice and Rationale of Health Practitioners in Prescribing a Bedtime Snack for Gestational Diabetes. Nutri Food Sci Int J. 2021. 10(5): 555800.DOI: 10.19080/NFSIJ.2024.10.555800.

Abstract

Evidence-based treatment of gestational diabetes (GD) is lacking. Many strategies used in the treatment and management of GD are from research in type 1 or 2 diabetes. A supper/bedtime snack is commonly recommended to manage overnight and fasting glucose. However, there is no evidence to support its effectiveness and the prevalence of its prescription by health professionals is unknown. Health professionals were invited to complete an online survey to explore what is currently recommended in practice in regard to advice about a supper/bedtime snack for clients with GD. 109 health professionals completed the survey, of these, 64 were dietitians, 39 diabetes educators and 6 others. Descriptive statistics were analysed, and Chi-Squared test was used to compare the distribution of responses between dietitians and diabetes educators. The top ranked, and thus frontline strategy to manage fasting hyperglycaemia in women with GD given by the health professionals surveyed, was advice to consume a bedtime snack/supper containing carbohydrate (CHO). 54% of Dietitians and 50% of Diabetes educators recommend consumption of a bedtime snack either ‘always’ or ‘most of the time’. The main reasons for recommending a bedtime snack were to i) lower fasting hyperglycaemia ‘dawn phenomenon’ and ii) to reduce the risk of nocturnal hypoglycaemia, which were not different between Dietitians and Diabetes educators. Dietitians ranked high protein third after low glycaemic index, contains carbohydrate, compared to diabetes educators who ranked low fat as the third most important nutritional factor (p=0.01). Dietitians based the advice to consume supper on professional experience compared to educators who based it off advice from colleagues. The results from this survey reveal the urgent need for a randomised controlled trial in women with GD. Given there remains much debate surrounding night-time eating and cardiometabolic health and that supper is often prescribed for GDM regardless of whether insulin or diet controlled, further research is warranted.

Keywords:Health Practitioners; Gestational Diabetes; Carbohydrate; Cardiometabolic Health; Nutrition

Introduction

Gestational diabetes is the most common complication of pregnancy, and with an increased prevalence of more than 30% in the last decade it is becoming the fastest growing type of diabetes worldwide [1]. Management of maternal glucose concentrations are pivotal in mitigating the complications of GD, such as excessive fetal growth and macrosomia, shoulder dystocia, instrumental and intervening deliveries [2]. Women with GD and their offspring also have a significantly higher risk of developing type 2 diabetes (T2D) later in life, compared to those without GD [1]. Cornerstone treatment for women with GD is medical nutrition therapy (MNT), followed by insulin if fasting glucose concentrations cannot be maintained within target range [3]. There is very limited evidence for best practice dietary advice in GD to help manage hyperglycaemia, with most studies being too small, short or designed without a control in order to provide strong evidence to determine which dietary intervention is best [4].

The meal in closest proximity to the overnight period (i.e., a bedtime snack or dinner) logically has the largest influence on fasting hyperglycaemia. Whilst epidemiological research suggests nighttime eating may be associated with adverse cardiometabolic outcomes [5]. Research has shown this depends on the food items consumed, with small or mixed-meals not appearing to be harmful and perhaps even being beneficial for cardiometabolic health [6]. Furthermore, in people with diabetes advice to consume a bedtime snack is often given to help control overnight and fasting glucose concentrations. Whilst there is no evidence to support this practice in the management of GD, this advice likely stems from mixed findings from research in type 1 and/or T2D [7-12]. Outside of popular media, it is unknown how widely a bedtime/supper snack is being recommended in clinical practice. The type of snack recommended, by whom, and the rationale for prescribing a supper snack in diabetes management is also not well understood. To this end, we conducted a survey in health professionals in Australia to explore the recommendation of a bedtime snack in the management and standard-care of gestational diabetes. This study will identify areas for future research and insight into current practices and guide future research into best-practice dietary intervention for the management of diabetes.

Methods

Data collection

Health professionals working in Australia and providing diabetes education to people with GDM and/or T2DM were invited to partake in a 15-min survey about the advice they provide to clients in regard to a bedtime snack (supper). Invitation to participate in this survey was via email and newsletters of professional organisations (Dietitians Association of Australia and the Nutrition Society of Australia (dietitians and nutritionists) and the Australian Diabetes Educators Association (diabetes educators). The survey was developed by researchers and clinicians working in diabetes and distributed to participants via the online platform CoreXM (Qualtrics, Sydney, Australia). This study was approved by the joint University of Wollongong and the Illawarra Shoalhaven Local Health District (ISLHD) Ethics Committee. Informed consent was provided by all participants.

The Survey

The first part of the survey collected information regarding sex, age, education, discipline/accreditation and training, years of experience. Followed by a series of questions, including multiple choice, likert, ranking and open ended questions, to explore what is currently recommended in practice in regard to advice about a supper/bedtime snack for clients with gestational diabetes and/ or type 2 diabetes and perceptions regarding this topic.

Data Analysis

Survey responses were exported from Qualtrics to Microsoft excel and then to IBM SPSS statistical software (Version 26.0. Armonk, NY: IBM Corp) for analysis. Descriptive statistics such as the crosstabs function were used to count the number of responses per health profession. The Chi-Squared test was used to compare the distribution of responses between dietitians and diabetes educators as they were the main responders to the survey. Responses from “other’ professions were excluded from this analysis as those included in the other category were of varied professions with limited numbers (n=6). A p-value of under 0.05 was deemed statistically significant. For baseline demographics (Table 1) an ANOVA was used to compare age between groups.

Results

119 health professionals began the survey, however 109 completed the survey and were included in analyses. Of these, 64 were dietitians, 39 diabetes educators and 6 others (Midwife, Physician and Pharmacist). Demographics and experience of participating health professionals are shown in Table 1. Diabetes educators were significantly older than Dietitians. Dietitians were significantly more likely to have received nutrition or dietetic training specific to diabetes management compared to Diabetes educators or other responders.

Health Professionals recommendation of a Bedtime Snack

The top ranked, and thus frontline strategy to manage fasting hyperglycaemia in women with GD given by the health professionals surveyed, was advice to consume a bedtime snack/ supper containing carbohydrate (CHO). This was ranked over the other options of insulin prescription, recommendation to not have supper/bedtime snack, exercise, and a low CHO bedtime snack. 54% of Dietitians and 50% of Diabetes educators recommend consumption of a bedtime snack either ‘always’ or ‘most of the time’. 90% of Diabetes educators recommend a bedtime snack to women with GD on insulin, compared to 72% of Dietitians (p=0.06). 69% of Dietitians and 53% of Diabetes educators recommend a bedtime snack to diet controlled women with GD. Only one Dietitian and zero Diabetes educators ‘never’ recommend a bedtime snack to women with GD. Of interest, 67% of Dietitians and Diabetes educators give similar advice to consume a bedtime snack to patients with T2D, whether they were treated with diet (31%), oral hypoglycaemic agents (40%) or insulin (64%).

What is recommended as a bedtime/supper snack?

The highest ranked nutritional factor that was considered to be the most important component in a bedtime/supper snack was to include low glycaemic index CHO. Dietitians ranked containing CHO (any type) being more important than Diabetes educators (ranked first and second by 76% of Dietitians compared to 60% of Diabetes educators, p=0.02). Having a bedtime snack that was low in fat was ranked less important, with no responses ranking this first, however there was a significant difference between Dietitians and educators (p=0.01) rankings; Diabetes educators were more likely to rank a low fat snack third highest (43% vs 13%) compared to Dietitians. Likewise, having a high protein snack was ranked less important, but instead significantly higher for Dietitians, with 61% ranking this third compared to 36% of Diabetes educators (p=0.01). There was also a significant difference in the amount of CHO recommended between Dietitians and Diabetes educators (p=0.01). A higher number of dietitians (28%) recommend 2 CHO exchanges (30g) compared to Diabetes educators (3%). Overall, most health professionals recommend 1 CHO exchange at supper (70%). Type of foods most commonly recommended, given by health professionals in the open ended question, are provided in Table 2.

Health Professionals reasons for recommending a bedtime snack

The main reasons for recommending a bedtime snack were to i) lower fasting hyperglycaemia ‘dawn phenomenon’ and ii) to reduce the risk of nocturnal hypoglycaemia, which were not different between Dietitians and Diabetes educators. 6% of Dietitians, compared to 27% of Diabetes educators, “Strongly Agree” supper is an effective intervention for preventing fasting hyperglycaemia in clients with GD (p=0.03), while 44% of dietitians, compared to 27% of Diabetes educators, “Agree” supper is an effective intervention. Reasons for not recommending a bedtime snack included i) causes unfavourable glycaemic response for clients (86% for Dietitians vs 57% for educators, p=0.03), and ii) exacerbates gastro-oesophageal reflux (78% for Dietitians vs 57% for educators, p=0.04). Diabetes educators more strongly relied on colleagues for sources of information regarding prescribing a bedtime snack (73%). Whereas the advice to consume a snack by Dietitians largely comes from professional experience/observation in working with clients (98%). Clients’ preference was ranked next for both Dietitians and Educators, with research articles (26%), professional qualifications/ program/course (31%) and clinical practice guidelines (54%) ranked lower (Figure 1).

Conclusion

Advice to consume a supper/bedtime snack is the frontline treatment approach given to women with GD to manage overnight and fasting hyperglycaemia. This recommendation is common amongst both Dietitians and Diabetes educators, the main responders to the survey. 50% of Dietitians and Diabetes educators either agree or strongly agree that supper is an effective intervention for improving fasting hyperglycaemia. There remains much debate surrounding night-time eating and cardiometabolic health [6]. Whilst a recent trial in people with T2D showed that a bedtime snack was neither detrimental nor beneficial compared to no bedtime/supper snack, a very low carbohydrate supper snack was superior to a moderate carbohydrate snack for improving nocturnal hyperglycaemia [11]. This is in line with other research in T2D comparing low GI/cornstarch to CHO-based controls [8- 10,12]. Given supper is widely recommended in the management of GD, further research is needed to determine its effectiveness and the optimal nutrient composition for controlling overnight and fasting hyperglycaemia. Indeed, supper could be a simple and cost effective strategy, if effective, to aid in the management of GD. The highest ranked nutritional factor considered to be the most important component in a bedtime/supper snack was the inclusion of low glycaemic index CHO, followed next by, contains CHO. This emphasis on CHO is in line with the clinical practice guidelines which recommend distributing CHO over the whole day [13].

The most commonly researched supper in T2D is cornstarch, likely because it is low GI with a lengthy digestibility of up to 6-9 hours [14,15]. However, high doses of corn starch can result in increased overnight glucose compared to a sandwich or a placebo [8,10] and resulted in no improvement to fasting glucose levels compared to sandwiches or placebo [9,10]. It is important to note that the corn starch dose was higher than the CHO typically recommended by health professionals in supper. Those surveyed mostly recommended one 15 g CHO exchange. However, a higher proportion of Dietitians did often recommend two exchanges compared to Diabetes Educators. The optimal amount of CHO and nutrient composition of supper remains to be determined. The third ranked important nutritional factor to incorporate into a supper/bedtime snack was significantly different between Dietitians and Diabetes educators. Here, Diabetes educators ranked low-fat third compared to Dietitians who ranked highprotein. Despite the published literature exclusively examining uncooked cornstarch bedtime snacks, many websites recommend a supper/bedtime snack containing protein. The rationale for protein has not been tested in the aforementioned cornstarch studies but is supported by research that shows high protein diets have beneficial effects on cardiometabolic health markers [16]. Additionally, the American Diabetes Association, suggests protein ingestion leads to an increase in the insulin response without an increase in blood glucose [17]. Indeed, individual amino acids have been proposed to have beneficial glucoregulatory effects; for example, glycine and leucine can stimulate enhanced glucose disposal by increasing insulin secretion and modulating insulin signaling [18].

This rationale is in line with the main reasons health professionals gave in their recommendation of a supper/bedtime snack; to i) lower fasting hyperglycaemia ‘dawn phenomenon’ and ii) to reduce the risk of nocturnal hypoglycaemia, which were not different between Dietitians and Diabetes educators.

There is limited evidence for the use of a bedtime snack/ supper in diabetes management. Whilst research has shown a low GI, and lower carbohydrate, bedtime snacks are more effective than higher carbohydrate/GI bedtime snacks [8-12] no study has shown a bedtime snack to be more effective than a control. The survey revealed that the prescription of a supper/bedtime snack is based on professional experience in working with clients and advice from colleagues, for Dietitians and Educators, respectively. A range of foods were provided in Table 2. Despite these being common food items, only three studies have utilised standard food interventions [9-11]. Therefore, collectively the results from this survey reveal the urgent need for a randomised controlled trial in women with GD. Given supper is being prescribed for T2D regardless of whether insulin or diet controlled, further research is also needed in other types of diabetes as well.

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