Exercise for glycaemic control in women with gestational diabetes mellitus

Summary

A meta-analysis and meta-regression «...»4 included 24 RCTs with a total of 3477 participants. Exercise lowered fasting blood glucose (FBG) (SMD -1.69, I²=96 %, p < 0.0001), 2-h postprandial blood glucose (2-hPBG) (SMD -2.10, I²=96 %, p < 0.0001), and glycated hemoglobin (MD -0.95, I²=98 %, p < 0.0001), although with high heterogeneity. Exercise reduced the risk of gestational hypertension (RR 0.24, I²=0 %, p < 0.0001), caesarean section (RR 0.71, I²=53 %, p = 0.0005), preterm birth (RR 0.51, I²=31 %, p = 0.002), macrosomia (RR 0.40, I²=19 %, p < 0.0001), and neonatal hypoglycemia (RR 0.49, I²=0 %, p = 0.03). Subgroup analyses indicated that moderate combined aerobic and resistance exercise improved FBG, 2-hPBG and the risks of cesarean section, preterm birth, and macrosomia. There was a significant dose-response relationship between exercise volume and 2-hPBG. The analysis found improvements, when exercise lasted at least 30 min per session, more than 3 times per week, for at least 6 weeks. All types of exercise were effective but combined aerobic and resistance exercise produced the greatest effect size.

A systematic review and Bayesian network meta-analysis «...»5 included 39 RCTs with information obtained from 2712 women assessing 15 treatments. Dietary approaches to stop hypertension (DASH) diet emphasizes the consumption of fruits, vegetables, whole grains, legumes, nuts, lean protein, and low-fat dairy products. The DASH diet reduced insulin requirements independently by 71% (95% credible intervals [CrI] 52% to 84%). Both the DASH (MD -587.6; 95% CrI: -752.12 to -421.85) and low glycaemic index diets (MD -180.09, 95% CrI: -267.48 to -94.65) reduced birth weight (low evidence). The DASH diet reduced macrosomia by 89% (95% CrI: 53% to 98%) and lowered the caesarean section rate by 46% (95% CI: 27% to , 60%).

A systematic review «Cremona A, O'Gorman C, Cotter A et al. Effect of e...»1 included 12 studies (2 with resistance training, 8 with aerobic exercise and 2 with a combination) with a total of 876 women. It was not possible to make a meta-analysis because the interventions (starting point, duration of exercise, length of intervention, and intensity) and diagnostic criteria varied. The interventions showed consistently that requirements of insulin therapy, dosage, and latency to administration were improved in the exercise groups. Exercising 3 times per week for 40-60 min at 65-75% age-predicted heart rate maximum using cycling, walking or circuit training as a modality improved glycaemic control in gestational diabetes (GDM) patients and reduced incidence of GDM in pregnant women with obesity. Less consistent results were observed for capillary blood glucose measurements; however, both modalities and combination of modalities were effective at improving blood glucose control in already diagnosed patients and pregnant women with obesity.

Another review and meta-analysis «Harrison AL, Shields N, Taylor NF et al. Exercise ...»2 included 7 RCTs involving 544 participants with GDM. Exercise, as an adjunct to standard care, significantly improved postprandial glycaemic control (MD -0.33mmol/L, 95% CI -0.49 to -0.17) and lowered fasting blood glucose (MD -0.31 mmol/L, 95% CI -0.56 to -0.05) when compared with standard care alone. Effects of similar magnitude were found for aerobic and resistance exercise programs, if performed at a moderate intensity or greater, for 20 to 30 minutes, 3 to 4 times per week. Exercise did not significantly reduced the requirement for insulin. Complications or other adverse events were either similar or reduced with exercise.

A third review «Allehdan SS, Basha AS, Asali FF et al. Dietary and...»3 included 8 RCTs involving 592 pregnant women and 350 infants. The combined diet and exercise interventions reduced fasting and postprandial blood glucose levels when compared to dietary interventions. No significant differences were reported in the selected trials regarding total weight gain during pregnancy, cesarean section, neonatal birth weight, macrosomia, neonatal hypoglycemia, and preterm birth between diet plus exercise and diet groups.