Sleep-wake patterns in newborns are associated with infant rapid weight gain and incident adiposity in toddlerhood

Background: Rapid weight gain (RWG) by 6 months of life is a significant risk factor of childhood overweight (OW)/obesity. Infant sleep patterns are associated with incident OW in childhood, but few have examined its relationship with RWG. Objective: Examine associations between newborn sleep-wake patterns and incident RWG at 6 months of life and OW at 36 months. Methods: Low-income Mexican/Mexican-American women with OW/obesity and their infants (n = 126) enrolled in a 1-year randomized controlled trial designed to prevent incident, infant RWG and toddlerhood OW/obesity. Sleep pattern metrics at 1 month were extracted from the Brief Infant Sleep Questionnaire-Revised. Outcome measures included RWG (>0.67 positive change in weight-for-age Z-score) from birth to 6 months and incident OW (body mass index percentile ≥85) at 36 months. Results: By 6 months, 35.7% (n = 45) of infants experienced RWG, and by 36 months 42.3% (n = 41) of toddlers were OW. Napping ≥5x/day at 1-month was significantly associated with decreased odds for RWG compared to napping <5x (OR = 0.11, 95%CI:0.02, 0.63). Each 1-hour increase in nocturnal vs diurnal sleep was associated with greater odds of incident OW at 36 mos (OR = 1.51, 95%CI:1.13, 2.03). Conclusions: Early-life sleep patterns related to infant nap frequency and nocturnal vs diurnal sleep distribution were associated with obesity outcomes and may be important intervention targets to prevent lasting consequences on infant growth.