▸ Pediatric asthma and obesity correlated, direction of associations unclear. ▸ Uses longitudinal data to test the associations between asthma and weight and asthma and activity levels. ▸ Past asthma associated with obesity and BMI, asthma onset associated with subsequent positive changes in BMI. ▸ Past BMI and obesity associated with subsequent asthma onset. ▸ Future research should explore mechanisms through which asthma may affect future weight outcomes.
Childhood obesity has become an issue of increasing concern to health researchers and policymakers in the United States. One important chronic health condition linked to obesity is pediatric asthma. Although researchers have speculated that both conditions may have common origins, the majority of research in this area has focused on a unidirectional relationship between obesity and later asthma. However, much of the literature is limited by its reliance on cross-sectional data and its failure to examine the possibility that asthma may influence weight fluctuations through changes in physical and sedentary activity. Using data from the Early Childhood Longitudinal Study-Kindergarten Cohort (ECLS-K), I explore the bidirectional relationships between childhood obesity and asthma. The results in this paper suggest that past asthma levels are positively correlated with changes in BMI and the onset of obesity. However, only new onset asthma is positively correlated with subsequent changes in BMI. The potential mechanisms are unclear, as I find little evidence that asthma is structurally related to changes in physical or sedentary activity over time. When testing the prevailing hypothesis that obesity is related to subsequent asthma, I find that lagged weight status is strongly related to asthma prevalence levels but that the onset of overweight or obesity is not associated with the subsequent onset of asthma. These results suggest that the onset of asthma may be related to subsequent weight gain over time.