Toddlers and obese children suffer more than other youth when exposed to secondhand smoke, according to research presented at the American Heart Association's Scientific Sessions 2009.
"Secondhand smoke in children is not just bad for respiratory issues, as has been previously described by other researchers," said John Anthony Bauer, Ph.D., the study's senior co-author and principal investigator at Nationwide Children's Hospital & Research Institute at Ohio State University in Columbus. "Our data support the view that cardiovascular effects of secondhand smoke in children are important, particularly for the very young and those who are obese. We had not investigated the impact of obesity in previous studies."
Bauer and colleagues recruited American boys and girls, including 52 toddlers (ages 2 to 5 years) and 107 adolescents (ages 9 to 18 years). The study included black, white and Hispanic children, including obese toddlers and adolescents.
The researchers found:
- There was a link between the amount of secondhand smoke exposure and a marker of vascular injury in toddlers. This link was two times greater in toddlers who were obese.
- Obese adolescents exposed to secondhand smoke had two times the evidence of vascular injury compared to normal-weight adolescents.
- Toddlers had a four times greater risk of secondhand smoke exposure when compared to adolescents, despite having similar reported home exposures.
- Toddlers exposed to secondhand smoke had a 30 percent reduction in circulating vascular endothelial progenitor cells, a cell type involved in repair and maintaining a healthy blood vessel network.
"The changes we detected in these groups of children are similar to changes that are well recognized risks for heart disease in adults," Bauer said. "This suggests that some aspects of adult heart disease may be initiated in early childhood, where prevention strategies may have great long-term impact."
Bauer and colleagues determined the extent of secondhand smoke exposures and, via blood samples, analyzed vascular injury markers and inflammation for each child. They also measured the numbers of circulating vascular endothelial progenitor cells. They obtained height, weight, blood pressure and socioeconomic information for each child studied.