Concentrations of certain exhaled volatile organic compounds are significantly higher in obese children than in nonobese children, according to findings from a controlled study involving more than 100 children.
The findings could lead to improved understanding of the pathophysiologic processes and pathways leading to childhood obesity, according to Dr. Naim Alkhouri of Cleveland Clinic Children’s Hospital.
Dr. Naim Alkhouri
These "breath prints" also could lead to interventions for childhood obesity, Dr. Alkhouri said at a press briefing held in advance of the annual Digestive Disease Week, where the data will be presented.
Mass spectrometry in 60 obese children and 55 lean controls demonstrated differences in the concentrations of more than 50 volatile organic compounds (VOCs). Four ion peaks were shown to identify overweight/obese subjects with 92% accuracy, he said.
Further analysis showed significantly higher concentrations of four VOCs in the obese vs. nonobese children after adjustment for age, height, and race. These included breath isoprene (11.6 ppb vs. 6.2 ppb), 1-octene (7.7 ppb vs. 4.6 ppb), ammonia (67.4 ppb vs. 50.1 ppb), and hydrogen sulfide (0.49 vs. 0.35 ppb), he said.
Overweight and obese study subjects were children recruited from a pediatric preventive cardiology and metabolic clinic; healthy controls were recruited from a general pediatric clinic during well-child visits. All underwent a single exhaled breath collection using selective ion flow tube-mass spectrometry.
The obese and lean groups differed significantly in that those in the obese group were older (mean of 14.1 vs. 12.1 years), taller (mean of 164.9 vs. 153.3 cm), and more likely to be white (60% vs. 35.2%).
"Obesity continues to be an epidemic in the United States and worldwide. We estimate that 17% of children in the United States are obese, and 32% percent are overweight," Dr. Alkhouri said, adding that these children are at risk for serious health complications, such as diabetes, obstructive sleep apnea, nonalcoholic fatty liver disease, and cardiovascular disease.
"We believe that these breath prints will shed light on the causes and complications of childhood obesity. This could have implications for early interventions as well as new and easier ways to screen for obesity-related complications," he concluded.
Dr. Alkhouri disclosed ties with Gilead Sciences, Vertex Pharmaceuticals, and Merck.