RESUMEN
Background: In trials testing the efficacy of diet and exercise modifications during pregnancy on health outcomes, assessment of participant adherence to interventions of diet and exercise is rarely reported, with few standard methods existing to measure adherence. Objective: We aimed to assess the maternal diet quality and create an algorithm to evaluate adherence to an intervention of high protein/dairy nutrition and walking exercise from early pregnancy to birth. Methods: In Be Healthy in Pregnancy randomized trial (NCT01693510), diet quality was measured using scores from an adapted PrimeScreen food frequency questionnaire, nutrient intake assessed by 3-day diet records, and physical activity using accelerometry at 14-17 (early), 26-28 (middle), and 36-38 (late) weeks' gestation. A novel adherence score was derived by combining data for compliance with prescribed protein and energy intakes and daily step counts in the intervention group. Between-group diet quality scores and changes in adherence scores in the intervention group across pregnancy were analyzed using generalized estimating equations adjusted for prepregnancy body mass index and study site. Results: Diet scores were similar for intervention (n = 55) and control (n = 56) groups at baseline but only the intervention group significantly improved and maintained their scores from early to middle (18.7 ± 7.6 vs. 22.9 ± 6.1; P < 0.001) and late (22.5 ± 6.9; P < 0.008) pregnancy. Protein intake was significantly (P < 0.001) higher but energy intakes were similar in the intervention group compared with those in the control group. Adherence scores for the intervention increased significantly (P < 0.01) from early (1.52 ± 0.70) to midpregnancy (1.89 ± 0.82) but declined from midpregnancy to late (1.55 ± 0.78; P < 0.0005) pregnancy primarily owing to lower step counts. Conclusions: Adherence to an intervention may decline toward the end of pregnancy, particularly in maintaining physical activity. Creation of adherence scores is a feasible approach to measure combined intervention compliance for diet and physical activity and may increase transparency in interpreting results of randomized trials in pregnancy.This trial was registered at clinicaltrials.gov as NCT01689961 (https://clinicaltrials.gov/ct2/show/NCT01689961?cond=NCT01689961&rank=1; registered on 21 September 2012).
RESUMEN
A randomized two-arm prospective superiority trial tested the efficacy of a novel structured and monitored nutrition (bi-weekly counselling for individualized energy and high dairy protein diet) and exercise program (walking goal of 10,000 steps/day) (intervention) compared to usual care (control) in pregnant women to achieve gestational weight gain (GWG) within current recommendations. Women recruited in communities in southern Ontario, Canada were randomized at 12-17 weeks gestation with stratification by site and pre-pregnancy BMI to intervention (n = 119) or control (n = 122). The primary outcome was the proportion of women who achieved GWG within the Institute of Medicine recommendations. Although the intervention compared to control group was more likely to achieve GWG within recommendations (OR = 1.51; 95% CI (0.81, 2.80)) and total GWG was lower by 1.45 kg (95% CI: (-11.9, 8.88)) neither reached statistical significance. The intervention group achieved significantly higher protein intake at 26-28 week (mean difference (MD); 15.0 g/day; 95% CI (8.1, 21.9)) and 36-38 week gestation (MD = 15.2 g/day; 95% CI (9.4, 21.1)) and higher healthy diet scores (22.5 ± 6.9 vs. 18.7 ± 8.5, p < 0.005) but step counts were similar averaging 6335 steps/day. Pregnancy and infant birth outcomes were similar between groups. While the structured and monitored nutrition with counselling improved diet quality and protein intake and may have benefited GWG, the exercise goal of 10,000 steps/day was unachievable. The results can inform future recommendations for diet and physical activity in pregnancy.
