Effect of an Antenatal Lifestyle Intervention on Dietary Inflammatory Index and Its Associations with Maternal and Fetal Outcomes: A Secondary Analysis of the PEARS Trial

Abstract

We investigated the effect of an antenatal lifestyle intervention of a low-glycaemic index (GI) diet and physical activity on energy-adjusted dietary inflammatory index (E-DII^TM) and explored its relationship with maternal and child health in women with overweight and obesity. This was a secondary analysis of 434 mother-child pairs from the Pregnancy Exercise and Nutrition Study (PEARS) trial in Dublin, Ireland. E-DII^TM scores were calculated for early (10-16 weeks) and late (28 weeks) pregnancy. Outcomes included lipids, inflammation markers, insulin resistance, mode of delivery, infant size, pre-eclampsia, and gestational diabetes. T-tests were used to assess changes in E-DII^TM. Chi-square, correlations, and multiple regression were employed to investigate relationships with outcomes. The mean (SD) age of participants was 32.45 (4.29) years with median (IQR) BMI 28.25 (26.70, 31.34) kg/m². There was no change in E-DII^TM in the controls (-0.14 (1.19) vs. -0.07 (1.09), <i>p</i> = 0.465) but E-DII^TM reduced by 10% after the intervention (0.01 (1.07) vs -0.75 (1.05), <i>p</i> < 0.001). No associations were found between early pregnancy E-DII^TM and maternal and child outcomes, except for increased odds of adverse cardiometabolic phenotype in women who delivered male (OR = 2.29, <i>p</i> = 0.010) but not female infants (OR = 0.99, <i>p</i> = 0.960). A low-GI antenatal intervention can reduce the inflammatory potential of diets. Sex differences should be explored further in future research.