Summary

Hearing loss has an impact on both physical and mental health. Researchers have carried out a survey in the United States and found it to be more prevalent than previously supposed. Some population groups are more at risk, and there are various factors, like smoking, that seem to be linked to hearing loss. More screening for hearing loss is needed, and it should begin earlier in young adulthood.

Introduction

Hearing loss, whatever its cause, has many harmful effects. It impairs communication and therefore leads to social isolation which can have a negative impact on health and quality of life. Both the aging of the population and the increased use of personal listening devices are likely to increase the prevalence of hearing loss in years to come. But until now there has been no accurate data on the magnitude of the problem in the United States. The best estimate is that 28 million people are affected, but this is based upon self-report which likely underestimates the true prevalence.

What was done

Researchers at Johns Hopkins Hospital used data from the National Health and Nutrition Examination Survey (NHANES) 1999-2004 to look at the extent of hearing loss among the American population. They carried out audiometric testing testing on a group of 5,742 adults and recorded both hearing loss at speech frequencies and at high frequencies. At the same time, they noted demographic characteristics, like age and ethnic origin, and noise exposure, smoking and cardiovascular risks which are known to be factors in hearing loss.

What was found

Around 16 percent of the group had speech frequency hearing loss in either one (nine percent) or both ears (seven percent). And 31 percent had high frequency hearing loss (12 percent in one ear and 19 percent in both ears). High frequency hearing loss was particularly a problem for participants in the 20 to 29 age group and in the 30 to 39 age group (8.5 percent and 17 percent, respectively). There was a significant increase in the prevalence of high frequency hearing loss among the 20-29 age group between 1999 and 2004.

Men were 5.5 times more likely than women to have hearing loss. But black people were 70 percent less likely to have hearing loss than whites. Mexican Americans had the highest occurrence of high-frequency hearing loss and hearing loss in both ears. Also, smoking, noise exposure and having cardiovascular risk factors increased the risk of hearing loss.

What this study means

According to this study, 29 million Americans aged 20 to 69 suffer from hearing loss, which is bigger than the previous estimate of 28 million for all age groups. Hearing loss is known to be very common among those over 70 who were not included in this study. This new study confirms deafness by audiometric measurements. Data based on self-report tends to be an underestimate, as people tend to deny or minimize their hearing loss. This study shows that hearing loss can start early, in a person4s twenties, so it is by no means a problem confined to the elderly. The increased use of listening devices has likely contributed to the increase in hearing loss, say the researchers. It also looks as if hearing loss first affects the higher frequencies of sound, beyond speech, which people may not be aware of - although it will affect their speech recognition. Therefore, hearing loss prevention and management should be offered to the population, and it should start in early adulthood.