Maternal Experiences of Racial Discrimination and Offspring Sleep in the First 2 Years of Life

Abstract

Purpose Insufficient sleep during infancy is associated with adverse child health outcomes including greater weight gain during infancy, childhood overweight, and developmental-behavioral conditions. Racial discrimination has been shown to be associated with shorter sleep duration in school aged children, adolescents, and adults; however, to our knowledge no studies have examined maternal experiences of lifetime racial discrimination and infant sleep duration. We hypothesize maternal lifetime experiences of racial discrimination will be associated with shorter infant sleep duration over the first 2 years of life Methods We analyzed data from 552 mother-infant dyads in Project Viva, a pre-birth cohort study, where the mothers self-identified as being women of color. During pregnancy, mothers completed the Experiences of Discrimination survey that measured lifetime experiences of racial discrimination in eight domains. We categorized responses as 0, 1-2, or ≥ 3. The main outcome was infant average 24 hour sleep duration assessed at 6 months, 1 year, and 2 years, reported by mothers, from which we calculated a weighted average of daily sleep across the first 2 years of life. In multivariable analyses, we adjusted for maternal race/ethnicity (black vs other women of color), education, household income, pre-pregnancy BMI, pregnancy smoking status, urbanicity, child care outside home, and child sex. Results Among this cohort, 30% of the mothers reported having experienced, up to and through the time of their pregnancy, 0 domains of racial discrimination, 35% reported 1-2 domains, and 34% reported ≥3 domains. Women who reported at least 1 domain of racial discrimination were more likely to be black (80.4% ), born in the United States (78.3%), and had higher pre-pregnancy BMI. Compared with children whose mothers reported no discrimination, those whose mothers reported ≥3 domains had shorter sleep duration from 6 months to 2 years in unadjusted analysis (β -0.31 h/d, 95% CI: -0.62 to 0.00), which was attenuated to -0.19 h/d, (95% CI: -0.52 to 0.14) after adjusting for maternal race/ethnicity, education, income, pre-pregnancy BMI, marital status, smoking history, childcare outside of the home, and urbanicity. We found stronger associations between maternal lifetime racial discrimination and offspring sleep at 6 months of age: β -0.79 h/d, (95% CI: -1.40 to -0.18) than for sleep at 1 year (β -0.21 h/d, 95% CI: -0.78 to 0.35) or 2 years (β 0.10 h/d, 95% CI: -0.33 to 0.52). Conclusion Although we observed no association between maternal lifetime experiences of racial discrimination and the mean duration of infant's sleep in the first two years, there was a suggestion of a modest association at 6 months postpartum.