Teenagers’ hearing is threatened by other people’s smoking, say researchers

NEW YORK—Researchers at New York University (NYU) School of Medicine have reported that exposure to tobacco smoke nearly doubles the risk of hearing loss among adolescents. Their findings were published today in the July 2011 issue of Archives of Otolaryngology–Head & Neck Surgery.

Anil Lalwani, MD, who led the research study, said that the results have “huge public health implications” since more than half of all children in the U.S. are exposed to second-hand smoke. Lalwani, a professor of otolaryngology, physiology and neuroscience, and pediatrics at NYU School of Medicine, added, “We need to evaluate how we deal with smoking in public places and at home, as well as how often and when we screen children for hearing loss.”.

Although the increased risk of lung cancer, heart disease, and other conditions caused by second-hand smoke is well established, this research is the first to link it to hearing loss.

More than 1500 Americans aged 12 to 19 participated in the study. They were selected from the 2005-2006 National Health and Nutrition Examination Survey, which collects health information from children and adults around the United States. The teenagers were initially evaluated in their homes and then given extensive hearing tests and blood tests for the chemical cotinine, a metabolite of nicotine, at a medical center.

Those teens whose blood tests showed exposure to second-hand smoke were more likely than others to have sensorineural hearing loss. Co-author Michael Weitzman, MD, a professor of pediatrics and psychiatry at NYU School of Medicine, described the subjects’ condition as “the type of hearing loss that usually tends to occur as one gets older, or among children born with congenital deafness.”

Teenagers exposed to smoke performed worse across every sound frequency tested, but especially in the mid-to-high frequencies crucial for speech understanding. Overall, the scientists conclude from the data that “tobacco smoke is independently associated with an almost two-fold increase in the risk of hearing loss among adolescents.”