School performance, race, and other correlates of sleep-disordered breathing in children

Childhood sleep-disordered breathing (SDB) has been associated with poor school performance. Both problems are common among African-American (AA) children, but potential confounders such as low socioeconomic status (SES) and obesity have not been well studied.

Children in second and fifth grades at six urban elementary schools were evaluated by teachers' ratings and year-end reading and math assessments. Risk for SDB was assessed with the validated parental Pediatric Sleep Questionnaire, and SES by qualification for school lunch assistance.

Among 146 children whose parents completed surveys, risk for SDB was associated with AA race, low SES, and poor teacher ratings (P<0.01), but not assessment scores (P>0.1). In multiple regression models, poor school performance was consistently and independently predicted by low SES (P<0.01) but not by AA race or SDB risk. Risk for SDB was associated with low SES before, but not after body mass index (BMI) was taken into account.

The SDB symptoms, AA race, and low SES all vary to some extent with poor school performance, but the only consistent and independent covariate of performance is SES. Risk for SDB is associated with low SES, perhaps because of a third variable, namely high BMI.