193: Does maternal genotype modify the effect of exclusive breastfeeding on postpartum weight retention?

ObjectiveTo determine whether maternal genetic variants modify the effect of exclusive breastfeeding (EBF) on postpartum weight retention.Study DesignIn a cohort of pregnant women we genotyped 248 self-identified Caucasian participants for 27 single-nucleotide polymorphisms (SNPs) associated with diabetes and obesity. We used linear regression to model the effect of genotype and interactions between genotype and EBF duration on retained weight at 3 and 12 months postpartum. All models were adjusted for pregravid BMI. Hierarchical selection was used to model quadratic and linear interactions between SNP carriage and EBF duration. P values <0.05 and interaction p values < 0.10 were considered statistically significant.ResultsThe average duration of EBF was 3.2 (SD 2.2) months. In models adjusting for pregravid BMI and gestational weight gain, duration of EBF was inversely associated with retained weight at 3 months (-1.3, 95% CI -2.1 to -0.5 lbs/month EBF) and at 12 months (-0.8, 95%CI -1.4 to -0.2 lbs/month EBF). At 3 months, we found a quadratic interaction between the diabetes-associated risk variant TCF7L2, EBF duration and retained weight. At 12 months, we found linear interactions between the diabetes-associated risk variants TCF2, JAZF1, and G6PC2, EBF duration, and retained weight (Figure). With further adjustment for gestational weight gain, for retained weight at 3 months, we found a quadratic interaction between TCF7L2 and EBF duration and a linear interaction between the variants SH2B1, INSIG2 and EBF duration. For retained weight at 12 months, we found linear interactions between JAZF1 and EBF duration.ConclusionsOur results provide tentative evidence that diabetes risk alleles may modify the effect of exclusive breastfeeding on maternal weight retention, but validation is needed in larger samples. ObjectiveTo determine whether maternal genetic variants modify the effect of exclusive breastfeeding (EBF) on postpartum weight retention. To determine whether maternal genetic variants modify the effect of exclusive breastfeeding (EBF) on postpartum weight retention. Study DesignIn a cohort of pregnant women we genotyped 248 self-identified Caucasian participants for 27 single-nucleotide polymorphisms (SNPs) associated with diabetes and obesity. We used linear regression to model the effect of genotype and interactions between genotype and EBF duration on retained weight at 3 and 12 months postpartum. All models were adjusted for pregravid BMI. Hierarchical selection was used to model quadratic and linear interactions between SNP carriage and EBF duration. P values <0.05 and interaction p values < 0.10 were considered statistically significant. In a cohort of pregnant women we genotyped 248 self-identified Caucasian participants for 27 single-nucleotide polymorphisms (SNPs) associated with diabetes and obesity. We used linear regression to model the effect of genotype and interactions between genotype and EBF duration on retained weight at 3 and 12 months postpartum. All models were adjusted for pregravid BMI. Hierarchical selection was used to model quadratic and linear interactions between SNP carriage and EBF duration. P values <0.05 and interaction p values < 0.10 were considered statistically significant. ResultsThe average duration of EBF was 3.2 (SD 2.2) months. In models adjusting for pregravid BMI and gestational weight gain, duration of EBF was inversely associated with retained weight at 3 months (-1.3, 95% CI -2.1 to -0.5 lbs/month EBF) and at 12 months (-0.8, 95%CI -1.4 to -0.2 lbs/month EBF). At 3 months, we found a quadratic interaction between the diabetes-associated risk variant TCF7L2, EBF duration and retained weight. At 12 months, we found linear interactions between the diabetes-associated risk variants TCF2, JAZF1, and G6PC2, EBF duration, and retained weight (Figure). With further adjustment for gestational weight gain, for retained weight at 3 months, we found a quadratic interaction between TCF7L2 and EBF duration and a linear interaction between the variants SH2B1, INSIG2 and EBF duration. For retained weight at 12 months, we found linear interactions between JAZF1 and EBF duration. The average duration of EBF was 3.2 (SD 2.2) months. In models adjusting for pregravid BMI and gestational weight gain, duration of EBF was inversely associated with retained weight at 3 months (-1.3, 95% CI -2.1 to -0.5 lbs/month EBF) and at 12 months (-0.8, 95%CI -1.4 to -0.2 lbs/month EBF). At 3 months, we found a quadratic interaction between the diabetes-associated risk variant TCF7L2, EBF duration and retained weight. At 12 months, we found linear interactions between the diabetes-associated risk variants TCF2, JAZF1, and G6PC2, EBF duration, and retained weight (Figure). With further adjustment for gestational weight gain, for retained weight at 3 months, we found a quadratic interaction between TCF7L2 and EBF duration and a linear interaction between the variants SH2B1, INSIG2 and EBF duration. For retained weight at 12 months, we found linear interactions between JAZF1 and EBF duration. ConclusionsOur results provide tentative evidence that diabetes risk alleles may modify the effect of exclusive breastfeeding on maternal weight retention, but validation is needed in larger samples. Our results provide tentative evidence that diabetes risk alleles may modify the effect of exclusive breastfeeding on maternal weight retention, but validation is needed in larger samples.