Human milk adiponectin affects infant weight trajectory during the second year of life

Abstract

Objective: Serum adiponectin (APN) is associated with lower childhood obesity, and APN concentration in human milk is associated with slower growth during active breast-feeding. We examined infant weight gain in the second year of life after exposure to high or low levels of mother's milk APN.

Methods: Breast-feeding mother-infant pairs were recruited in Mexico City and studied for 2 years; 192 infants with at least 12 months' follow-up were analyzed. Monthly milk samples were assayed for APN; mothers were classified as producing high or low levels of milk APN. Infant and maternal serum APN were assessed during year 1. Infant anthropometry was measured monthly (year 1) or bimonthly (year 2), and World Health Organization z scores were calculated. Longitudinal adjusted models assessed weight-for-age and weight-for-length z score trajectories from 1 to 2 years.

Results: Maternal serum APN modestly correlated with milk APN (r=0.37, P<0.0001) and infant serum APN (r=0.29, P=0.01). Infants exposed to high milk APN experienced increasing weight-for-age and weight-for-length z scores between age 1 and 2 years in contrast to low milk APN exposure (P for group × time=0.02 and 0.054, respectively), adjusting for growth in the first 6 months and other covariates. In contrast, infant serum APN in year 1 was not associated with the rate of weight gain in year 2.

Conclusions: High human milk APN exposure was associated with accelerated weight trajectory during the second year of life, suggesting its role in catch-up growth after slower weight gain during the first year of life.

Conflict of interest statement

Disclosure Statement

LJM and ALM are listed on a U.S. patent application claiming human milk adiponectin as an oral treatment for adiposity and inflammatory disorders, and LJM received a portion of a licensing fee for this technology. The remaining authors report no conflicts of interest.

Figures

Figure 1. Maternal median milk adiponectin in above- versus below-median groups

N per group: n=3, 29, 38, 140, and 67 with 1, 2, 3, 4, or 5 measurements, respectively. Median and interquartile range (IQR) presented.

Figure 2. Descriptive presentation of breastfeeding and anthropometry

A. Infant feeding patterns for exclusive breastfeeding (EBF), BF >85% and introduction of solid foods. B. Unadjusted means (± standard error of mean [SE]) of WEI, WFL and LEN Z-scores by month. Vertical solid lines indicate 3, 6 and 12 months of age for visual reference.

Figure 2. Descriptive presentation of breastfeeding and anthropometry

A. Infant feeding patterns for exclusive breastfeeding (EBF), BF >85% and introduction of solid foods. B. Unadjusted means (± standard error of mean [SE]) of WEI, WFL and LEN Z-scores by month. Vertical solid lines indicate 3, 6 and 12 months of age for visual reference.

Figure 3. Infant and mothers’ serum adiponectin concentrations during first 12 months

Analysis conducted using means and standard errors; however, unadjusted median and IQR are presented for graphical clarity. p≤0.002 for all pairwise comparisons of means among infant serum values; p

Figure 4. Year 2 infant growth trajectories by adiponectin concentrations

Least square means ± SE presented from fully adjusted models. A. WEI Z-score, Milk adiponectin; B. WFL Z-score, Milk adiponectin; C. WEI Z-score, Infant serum adiponectin; D. WFL Z-score, Infant serum adiponectin; E. WEI Z-score, Maternal serum adiponectin; F. WFL Z-score, Maternal serum adiponectin. APN: Adiponectin. *p≤0.05 for adjusted pairwise comparison between high and low groups.