Public Release: 

Kids with asthma that are exposed to secondhand smoke have twice as many hospitalizations

Mayo Clinic

ROCHESTER, Minn. -- The risk for hospitalization doubles for kids with asthma who are exposed to secondhand smoke, according to a study led by Mayo Clinic Children's Research Center. "The results of this review serve as a reminder to parents of just how dangerous it is to expose their children to secondhand smoke," says Avni Joshi, M.D., senior author and pediatric allergist and immunologist at Mayo Clinic Children's Center. "We knew that kids should not be exposed to tobacco, but how bad their asthma is likely to be with tobacco exposure was not clear. This study helped us quantify that risk, and so it informs as well as empowers us with the risk assessment. A child is twice as likely to end up in the hospital with an asthma flare if family members continue to smoke."

The study published in the Annals of Allergy, Asthma and Immunology strengthens the association that previous studies have shown which links secondhand smoke exposure with increased asthma prevalence, poorer asthma control and increased symptoms.

The research team did a review of 25 studies looking at smoking exposure at home. More than 430,000 children were included in the review, with a mean age of 7.6 years. The majority of the studies -- 96 percent -- investigated smoking exposure at home.

"The study also illustrates the increased burden of disease on the health care system with increased rates of hospitalization," says Dr. Joshi. "The children are missing school if they are hospitalized, and the parents miss work. It is a big financial burden for the family, as well as for society. A child being hospitalized has a high risk of hospital-acquired infection, so I think this is fairly serious."

It drives home the point for parents that, if your child is twice as likely to be hospitalized, you should make some changes in your life and try to quit smoking, Dr. Joshi says.

Dr. Joshi's team understands how hard it is to quit smoking, so her team worked with the Nicotine Dependence Center and the Center for Innovation at Mayo to develop a program that helps families kick-start their effort to tobacco control. The program provides nicotine counseling and nicotine replacement supplies free of cost to family members with children who have asthma during the child's clinic appointment in the children's center. This family-based program puts the child at the center for the change. Many times people won't change for themselves, but they do more so for their children, adds Dr. Joshi.


The study was funded by the Center for Innovation. Other study authors are Zhen Wang, Ph.D., Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, Mayo Clinic; Sara May, M.D.; Suvanee Charoenlap, M.D., King Chulalongkorn Memorial Hospital, Bangkok, Thailand; and Regan Pyle, D.O., Allergy & Asthma Consultants, St. Louis, Mo.

About Mayo Clinic

Mayo Clinic is a nonprofit organization committed to medical research and education, and providing expert, whole-person care to everyone who needs healing. For more information, visit or


Kelley Luckstein, Mayo Clinic Public Affairs, 507-284-5005,

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.