Children who are exposed to second-hand smoke are at risk of developing a variety of health problems. On the one hand, there are respiratory infections and behavioural difficulties but on the other hand the problems also include acute ear infections (otitis media) which can increase the risk of hearing loss during adolescence. Especially babies, whose mothers were exposed to second-hand smoke in pregnancy, are at a greater risk of low birth weight. In addition, children who are exposed to passive smoke are at an increased risk of developing recurrent middle ear infections.
One of the authors of the study confirms: â€œSecond-hand smoke may also have the potential to have an impact on auditory development, leading to sensorineural hearing lossâ€.
The researchers of the study discovered, that the risk of hearing loss among participants exposed to second-hand smoke was 1.5 times that of the non-exposure group.
The study was carried out by the New York University Langone Medical Centre and included 1,533 teens in America aged between 12 to 19 years. The participants were questioned about their health status and family medical history, their exposure to second-hand smoke and their knowledge of whether or not they had a hearing problem. In a medical examination the teens underwent a hearing test and were tested for cotinine, a degradation product of nicotine. The researchers found that the higher the level of continine in the blood, the higher the rates of low- and high-frequency hearing loss could be detected. Beyond this, the study also showed that more than 80% of the teens suffering from hearing loss did not even realise they had a hearing impairment.
In this type of hearing loss, pathological changes in the auditory nerve and the inner ear cause acoustic signals to be transmitted incorrectly. The researchers of the study suggest that adolescents who are exposed to passive smoke should be more closely monitored for hearing impairment. Furthermore they should be educated about the risk factors of hearing loss, such as noise pollution and second-hand smoke.