by Neil Bauman, Ph.D.
Who would have thought that hearing loss would be tied to sleep apnea? Yet that is exactly what researchers recently discovered.
Sleep apnea (AP-nee-ah) is a disorder in which you have one or more pauses in breathing or shallow breaths while you sleep. Breathing pauses can last from a few seconds to minutes. They may occur 30 times or more an hour.
In a study of 13,967 people with sleep apnea, 9.9% of this population had at least moderate sleep apnea.
Researchers defined moderate sleep apnea as 15 or more sleep apnea events per hour. Sleep apnea events included apneas (complete cessation of airflow) and hypopneas (partial cessation of airflow).
In this same population, 19.0% had high-frequency hearing loss. (Note: the researchers defined high frequency hearing loss as hearing loss greater than 25 dB at 2, 3, 4, 6 and 8 kHz. They defined low-frequency loss as hearing loss greater than 25 dB at 0.5 and 1 kHz). 8.4% of the study population had both high and low frequency hearing loss. Only 1.5% had just low-frequency hearing loss.
After adjusting for a number of factors, sleep apnea was associated with a 31% increase in people with high-frequency hearing loss, a 38% increase in people with both high and low frequency hearing loss and a 90% increase in people with low-frequency hearing loss.
Interestingly enough, as the number of apnea events increased (above the baseline 15 events per hour) so did the percentage of people with high-frequency hearing loss. However, there was no such correlation in those with low-frequency hearing loss.
Researchers also found that hearing loss was more prevalent among people with a higher body mass index (are overweight), and those that self-reported they snored or had sleep apnea.
What causes this increase in hearing loss in people with sleep apnea? According to lead author, Dr. Amit Chopra, “Potential pathways linking sleep apnea and hearing impairment may include adverse effects of sleep apnea on vascular supply to the cochlea [reduced blood (and thus oxygen) reach the inner ear] via inflammation and vascular remodeling or noise trauma from snoring.” (Perhaps they also need to do a study on hearing losses in wives caused by their husband’s snoring.)
Therefore, if you have sleep apnea, it would seem wise to seek treatment for it before it causes you (more) hearing loss.