A new study shows that children’s exposure to secondhand smoke markedly increases the odds of being readmitted to the hospital for asthma.

The American Lung Association (ALA) identifies secondhand smoke as, “exhaled smoke from smokers and side stream smoke from the burning end of a cigarette, cigar or pipe,” and estimates that 400,000 to 1,000,000 children with asthma have the condition worsened by exposure to secondhand smoke.

The new findings were published in the Pediatrics medical journal and the authors believe that measurement of tobacco exposure can be used to bolster smoking cessation efforts to reduce hospitalizations, according to a statement.

The researchers studied more than 600 children between the ages of 1 and 16 who were admitted to the Cincinnati Children’s Hospital and they collected cotinine levels from the children and recorded information about tobacco exposure. The subjects were followed for at least 12 months to see how many were readmitted to the hospital for treatment. Cotinine is a substance created when the body processes nicotine.

The researchers found that, “measurement of cotinine in the blood and saliva demonstrated a readmission risk in children exposed to secondhand smoke more than twice that of children not exposed.”

Senior author of the study Robert Kahn, MD, MPH, at Cincinnati Children’s Hospital believes the ability to measure cotinine levels “presents the possibility of an objective measure that can be obtained when a child is seen in the emergency department or in the hospital and may be used to predict future hospitalizations.”

Kahn says that the ability to measure tobacco levels could be used to “target specific interventions at caregivers of those children before discharge from the hospital. Several interventions, including parental counseling and contact with the primary care physician, could be adopted in clinical practice.”

The ALA identifies asthma as the third-leading cause of hospitalization among children younger than 15 years old. It estimates the direct annual health care cost of asthma at approximately $50.1 billion with indirect costs adding another $5.9 billion on top.

“Certainly there could be a financial incentive for insurance companies to help caregivers quit smoking, rather than pay the downstream costs of a future asthma readmission,” said lead author of the study Judie Howrylak, MD, PhD with Hershey Children’s Hospital.

Researchers from Cincinnati Children’s Hospital Medical Center and Penn State Milton S. Hershey Children’s Hospital collaborated on the study, seeking to understand the causes of hospital readmission for low-income and minority children as part of the Greater Cincinnati Asthma Risks Study.