Exclusive human milk diet is associated with lower risk of motor function impairment at three years of corrected age

Abstract

Objectives: To evaluate the association between an exclusive human milk diet (EHMD) and motor function impairment at three years of corrected age among infants born before 32 weeks of gestation.

Methods: We conducted a retrospective study between 2018 and 2021. We assigned to the EHMD group infants who received an EHMD for ≥75% of the days between the first day of diet fortification and 33 6/7 weeks postmenstrual age. We used inverse propensity scores to balance potential confounders and developed a mixed-effects logistic regression model to assess the association.

Results: After adjusting for demographics and morbidities, an EHMD was associated with a reduced risk of motor function impairment, with an odds ratio of 0.74 (95% CI: 0.56-0.98, p = 0.036).

Conclusions: An EHMD is associated with a decrease in the odds of early childhood motor function impairment among infants born before 32 weeks of gestation.

Fig. 1. Comparison of feeding practices between infants on an exclusive human milk diet (EHMD) and non-EHMD group.

A A histogram illustrating the distribution of the percentage of days infants received an EHMD between the first day of fortification and 33 6/7 weeks postmenstrual age. The EHMD group was arbitrarily defined as having ≥ 75% of days on an EHMD, whereas the non-EHMD group was defined as having <75% of days on an EHMD. B Boxplots comparing caloric density by day for the first 21 days after diet fortification began between the EHMD and non-EHMD groups. Each boxplot displays the median (thick horizontal line), 25th and 75th percentiles (box edges), and whiskers extending to 1.5 times the interquartile range above and below the percentiles. Dashed lines (dark grey for EHMD, light grey for non-EHMD) indicate the median caloric density for each group over time.

Fig. 2. Association of an exclusive human milk diet (EHMD) with motor function outcomes at three years of corrected age.

A forest plot illustrating odds ratios (represented by black dots) and 95% confidence intervals (depicted as whiskers) for motor function impairment, comparing the EHMD and non-EHMD groups, along with significant confounders and covariates. The vertical line at an odds ratio of 1 indicates no effect. Confounders and covariates adjusted in the model include gestational age groups, antenatal corticosteroids, grade 1/2 intraventricular hemorrhage, grade 3/4 intraventricular hemorrhage, ibuprofen/indomethacin treatment, postnatal corticosteroids, grade 2/3 bronchopulmonary dysplasia, and birth weight percentile.