The association between mothers' reports of cell phone use by children and hearing loss at the age of 7 years was investigated in a cohort study in Denmark. Further aims of studies were to examine whether hearing loss at age 18 months affects mobile phone use at the age of 7 years.
When the children reached seven years of age, mothers were invited to complete a questionnaire that focused on the child's exposures (child's mobile phone use at the age of 7 years), lifestyle and health problems (permanent hearing loss at the age of 7 years).
|Reference group 1||no mobile phone use at the age of 7 years|
|Group 2||mobile phone use at the age of 7 years|
Permanent hearing loss at the age of 7 years was reported in 836 (1.6%) children. While 1405 (2.7%) children reportedly had a diagnosis of reduced hearing at age 18 months, only 6% (n=82) of them also had permanent hearing loss at age 7 years according to mothers' reports. Approximately 36% (n=18,935) of children used a mobile phone at the age of 7 years, but less than 1% used it more than 1 hour per week.
Weak associations between mobile phone use and hearing loss at age 7 were observed (traditional logistic regression: OR 1.21, CI 0.99-1.46; MSM model: OR 1.23, CI 1.01-1.49; DRE model: OR 1.22, CI 1.00-1.49). No association between reduced hearing at the age of 18 months and mobile phone use at the age of 7 years was found.
The authors stated that their findings could have been affected by various biases and are not sufficient to conclude that mobile phone exposures have an effect on hearing.