Obesity, sleep apnea and cognitive problems linked in kids

Obesity, sleep-disordered breathing (SDB) and cognitive processing are all interlinked among elementary school children, US researchers say.

Researchers from the University of Chicago enrolled 351 schoolchildren in Louisville, Kentucky, who underwent neurocognitive testing with the Differential Abilities Scale following an overnight polysomnogram or sleep study.

SDB was measured with the obstructive apnea/hypopnea index (AHI), defined as the number of apnea and hypopneas per hour of total sleep time and anthropometric measurements included body mass index (BMI).

The data were analysed by Structural Equation Modeling, a statistical technique for testing and estimating causal relations between the variables of interest.

“The intricate interdependencies between BMI, SDB and cognition shown in our study are of particular importance in children, as their brains are still rapidly developing,” Karen Spruyt, the study author, said.

“Rising rates of obesity in children may amplify these relationships. Public health campaigns targeting obesity should emphasize not only the health benefits but the potential educational benefits of losing weight,” she said.

Models using “sleep-disordered breathing” revealed a substantive mediator role of SDB on the relationship between BMI and cognitive performance, with SDB increasing both adverse cognitive and adverse weight outcomes.

In analyses using “weight”, BMI increased the risks of adverse SDB and cognitive outcomes, and finally, in models using “cognition” as the mediator, the poor ability to perform complex mental processing functions was shown to increase the risk of adverse weight and SDB outcomes

“SDB amplified the risk of adverse cognitive and weight outcomes, while weight amplified the risk of SDB and adverse cognitive outcomes. Impaired cognitive functioning was associated with an increased risk of adverse weight outcomes and SDB,” Spruyt added.

The study will be published in the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine.