Socioeconomic Position and Heart Rate Recovery After Maximal Exercise in Children

Objective: To determine whether socioeconomic (SE) position is associated with first-minute (1-minute) heart rate (HR) recovery in healthy children and adolescents (hereafter referred to as children). Design: In a cross-sectional study, we compared 1-minute HR recovery in 3 groups of children (low, medium, and high SE) using multivariable analysis. The groups were based on neighborhood SE data extracted from the US 2000 census database. Setting: Children's Hospital Boston. Participants: Four hundred eighty children referred for exercise testing to exclude cardiac disease and discharged as showing normal results. Main Exposures: Socioeconomic position and body mass index (BMI). Main Outcome Measure: Heart rate recovery after a maximal treadmill exercise test (Bruce protocol) following a consistent 1-minute cool-down period. Results: The low SE group had a higher proportion of children with a high BMI (>= 85th percentile) (P = .07) and exercised for a shorter duration, controlling for age, sex, and BMI (P < .001). After adjusting for age (P < .001) and sex (P < .001), a significant interaction of SE group with BMI was found (P = .04). There was no difference in HR recovery in the 3 SE groups in children with a normal BMI (<85th percentile). Among children with a high BMI, only those from low and middle SE neighborhoods had impaired 1-minute HR recovery. Conclusion: Children with a high BMI in low and middle SE positions appear to have worse cardiovascular health compared with children with a high BMI in a high SE position.