Do pregnancy outcomes differ by mode of insulin delivery for type 1 diabetes mellitus?

Abstract

Prenatal lifestyle intervention studies that limit gestational weight gain (GWG) have largely failed to reduce the rate of gestational diabetes mellitus (GDM), suggesting that prenatal interventions may be too late to provide benefit. The objective of this study was to determine the independent association of periconceptional diet quality on gestational glycemia and frequency of GDM. STUDY DESIGN: This is a secondary analysis of 9566 nulliparous pregnant women from the nuMoM2b cohort with a GDM classification (yes/no), and a subset of 1323 women with available data from a 3-hr 100g glucose tolerance test (GTT) at a mean gestational age of 28.7AE7.2 weeks. Subjects reported their usual dietary intake over the preceding 3 months by food frequency questionnaire in early pregnancy (6-13 weeks). The Alternative Healthy Eating Index (AHEI)-2010 was computed as a continuous index score of periconceptional diet quality. Logistic regression was used to estimate the association between the AHEI score and odds of GDM. The association between the AHEI score with each hourly GTT result was tested in separate linear regression models. All models were adjusted for confounding factors (maternal age, self-identified race/ethnicity, pregravid body mass index (BMI), smoking) and a sensitivity analysis was performed with additional adjustment for rate of GWG per week. RESULTS: The mean pregravid BMI among those eligible for inclusion was 26.3AE6.3 kg/m 2 and 46% were overweight or obese. The GDM frequency was 4.1% overall and 21.3% among those who underwent a 3-hr GTT. Higher diet quality was associated with a reduced risk of GDM (beta¼-0.02, p¼0.004, OR¼0.98, 95% CI 0.97-0.99). Diet quality was inversely associated with blood glucose values at each GTT measurement (Table 1). Additional adjustment for rate of GWG did not alter the significant results. CONCLUSION: After accounting for confounding factors and GWG, poor periconceptional diet quality remained a risk factor for elevated GTT values and GDM in a diverse cohort of nulliparous women. Periconception intervention studies targeting women's diet quality are warranted.