None listed
Conditions
Brief summary
Diabetes in pregnancy is the most common metabolic dysfunction in pregnancy. Many women are managed with diet control alone. It is therefore essential that women are receiving accurate nutritional advice. Current practice at our hospital is to advise women to have a bedtime snack to help meet the caloric requirements of pregnancy, and with the expectation that it may suppress hepatic gluconeogenesis thus achieving lower fasting blood glucose levels (BGLs). Recommending supper in GDM is widely practiced across Australia and is contained in the Dietitians Association of Australia resources, and supported by the Canadian and American Diabetes Associations’ Guidelines; however, there is no strong or recent evidence to support this. This study aims to recruit 66 women and measure the effect of two different snacks: a higher carbohydrate snack (apple and yoghurt) and a lower carbohydrate snack (nuts and dark chocolate) as compared to no snack, to see what influence each of these has on fasting BGLs. Each snack will be consumed for five consecutive days. Women will be randomly allocated an order in which to consume each snack. Women will also be required to record their activity levels each day, in order to monitor the effect that this has on fasting BGLs It is expected that women will have lower fasting BGLs when consuming either snack than when they are not having a snack. It is also expected that those women with higher physical activity levels will have lower fasting BGLs.
Interventions
Women will be informed of the study at their first education class. Women will be enrolled into the study following their initial Dietitian review if they have greater than or equal to two fasting BGLs in the preceding week between 4.7-5.4 mmol/L and post-prandial levels not requiring insulin treatment, following informed consent being obtained. The dietitians delivering the intervention all have extensive clinical experience of a minimum of 5 years. There is not expected to be any carry-over e
Women will be informed of the study at their first education class. Women will be enrolled into the study following their initial Dietitian review if they have greater than or equal to two fasting BGLs in the preceding week between 4.7-5.4 mmol/L and post-prandial levels not requiring insulin treatment, following informed consent being obtained. The dietitians delivering the intervention all have extensive clinical experience of a minimum of 5 years. There is not expected to be any carry-over effect of the treatments so the "wash out" period between treatments is the intervening daytime only. Participants will be asked to: a take a standardised, healthy carbohydrate based snack for five days b take a standardised, higher protein, lower carbohydrate snack for five days c have five days without any supper snack d The snack will be consumed at least 2 hours after dinner (between 7pm and 12am depending on the timing of their dinner between 5pm and 8pm) e record fasting and post-prandial BGLs daily for the fifteen day period f record activity levels (low/moderate/high) intensity and record sleep quality (poor/moderate/good) each day If they consent to participating in the study, they will be randomly allocated to an order in which to take their snacks: 1 Higher carbohydrate snack: Yoghurt tub (175g) and an apple (medium ~150g) Yoghurt = 88cal, 12.3g CHO, 8.8g protein, 0.2g fat Apple = 68cal, 14.6g CHO, 0.4g protein, 0g fat TOTAL = 156cal; 26.9g carbohydrate; 9.2g protein, 0.2g fat 2 Lower carbohydrate snack: Almonds (10 nuts) and 2 squares (20g) of dark chocolate Almonds = 72cal, 0.6g CHO, 2.3g protein, 6.6g fat Dark chocolate = 112cal, 6.8g CHO, 1.9g protein, 8.2g fat TOTAL = 184cal; 7.4g CHO, 4.2g protein, 14.8g fat 3 No snack Food will be provided to the study participants in esky containers for transport home. It will be prepared by kitchen staff at the hospital. Women will record their BGLs, quality of sleep and activity levels each day on a record sheet provided to them (attached). They will also record with a tick whether they complied with the prescribed snack. As the patients are not on insulin there are no safety concerns regarding missing an evening snack. If a participant requires insulin while the study is ongoing (as decided by the physician) then their participation in the study is ceased.
Sponsors
Dr Dorothy Graham
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to 50 Years
Healthy volunteers
No
Inclusion criteria
a Have gestational diabetes diagnosed on routine oral glucose tolerance test. OGTT will diagnose gestational diabetes if fasting BSL is greater than or equal to 5.1, 1 hour reading is greater than or equal to 10, 2 hours greater than or equal to 8.5. b Be on diet control (no oral hypoglycaemic agents or insulin) c Have two or more fasting BGLs of 4.7-5.4mmol/L in the week prior to recruitment d Have a singleton pregnancy e Are between 24 and 34 weeks gestation f Have not had hospital admissions or Celestone therapy for the 2 weeks of the study g Have no food allergies or intolerances that preclude them taking the snack h Are compliant with BGL monitoring i Fasting BGL recorded between 6am to 8am with a minimum time of 8 hours since their evening snack j Are capable of giving informed consent k Are women aged greater than or equal to 18 years of age l Have dinner between the hours of 5pm and 8 pm, with a 2 hour minimum time between evening meal and evening snack
Exclusion criteria
a Requiring NovoRapid (fast acting insulin) with meals or requiring Protaphane (long acting insulin) during the two week period (as per treating physician’s decision) b Patients on metformin or other medications which may affect glucose metabolism (as per treating physician’s decision) during the study c Shift workers, or irregular meal times for any other reason d greater than or equal to 3 fasting BGLs greater or equal to 5.2mmol/L in the week prior to recruitment e Macrosomic foetus, defined as AC greater than 90 percentile or polyhydramnios f Women who require an interpreting service g Women who have had bariatric surgery
Outcome results
None listed