0984 Less Consistent Bedtimes Explains The Relationship Between Household Poverty And BMI In Toddlers

Abstract

Listen

Translate article

Abstract Introduction Consistent bedtimes, in conjunction with physical activity and diet have been linked to healthy weight in childhood. Young children living in impoverished families are at risk for obesity, and the mechanisms of obesity etiology are not fully understood. This study compares the role of bedtime consistency, physical activity and diet quality as mediators between household poverty and toddler weight gain. Methods 207 toddlers participating in an obesity prevention trial wore Actical accelerometers for up to 7 consecutive days, at 3 time points over 12 months. At each assessment, gender-specific BMI-for-age z-scores (zBMI) were calculated from toddlers’ weight/length according to WHO standards. Household poverty ratio was calculated based on the number of household members and annual income. Diet quality was assessed using Healthy Eating Index (HEI-2015) from 24-hour dietary recall. Physical activity and sleep were measured using ankle accelerometry (Actical; Sadeh algorithm used for sleep). Bedtime consistency was defined as SD of sleep onset across 7 days. A multi-level mediation model was conducted in the SPSS macro MLmed examining toddler bedtime consistency, physical activity and diet quality as mediators between household poverty and toddler zBMI. The analysis adjusted for toddler age, gender, total sleep time and intervention group. Results Between-person effects revealed that less household poverty was associated with more consistent bedtimes. Children with less consistent bedtimes, but not poor diet quality or physical activity, had higher zBMI. Bedtime consistency indirectly explained the association between average household poverty and average toddler zBMI over 12 months. Conclusion Children who generally have less bedtime consistency, above and beyond physical activity and diet quality, had higher zBMI. This link uniquely indirectly explained the association between household poverty and zBMI. Inconsistent bedtimes may indicate lack of structure in other health behaviors, and therefore, continued longitudinal research examining family routines may inform obesity prevention strategies. Support Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), R01HD056099