Background: Most observational research examining factors in the home environment that contribute to child adiposity has focused on feeding and physical activity, although aspects of one's nonfood home environment such as parent-child interactions can also impact body weight. The main objectives of this study were to determine if parent-infant interactions under different contexts provide a unique contribution to infants' concurrent adiposity after accounting for known obesity-related covariates. Methods: This was a cross-sectional analysis of 121 9- to 15-month-old infants using data collected at the baseline visit of an ongoing intervention study. Mother-infant interactions during a feeding episode and a free-play task were recorded and coded. Anthropometrics of infants were measured by trained research staff. We used two-step hierarchical multivariable regression models to examine the unique contribution of mother-infant interactions to weight status after accounting for known obesity-related covariates (i.e., maternal age, BMI, education, parity, and gestational age, child sex, breastfeeding duration, age of solid food introduction, and birthweight). Results: Maternal intrusiveness, child negative affect, and child responsiveness during free-play, but not feeding were significantly associated with z-weight-for-length. For every 1-U increase in maternal intrusiveness and child negative affect there was a 0.321 (p = 0.011) and 0.415 (p = 0.028) unit increase in z-weight-for-length, respectively, whereas for every 1-U increase in child responsiveness there was a decrease of 0.386 U in z-weight-for-length (p = 0.025). Conclusion: This research contributes new findings support the idea that parent-child interactions outside of the feeding context may relate to obesity. Clinical Trial Registration Number NCT02936284.
Keywords: child negative affect; child responsivity; feeding; free-play; infant obesity; maternal intrusiveness; parenting.