by Daniel Fink, MD, Chair, The Quiet Coalition
A recent study in The Lancet shows that people with hearing loss who used hearing aids had dramatically reduced mortality. This research is now getting a wealth of media attention. National news agencies like NPR covered it, as did CNN. For further reading, I have included a link to the scientific article and an editorial commenting on the study.
The study was based on an analysis of data about hearing loss and hearing aid use collected from 1999-2012 in the Center for Disease Control and Prevention’s National Health and Nutrition Evaluation Survey (NHANES). The National Death Index captured deaths of the individuals participating in the study. The takeaway from the study was that people with hearing loss who wore hearing aids regularly had dramatically reduced all-cause mortality over an average 10.4 year follow-up time. Those who wore hearing aids were 24% less likely to die over that time period.
My initial reaction when I read the news was that hearing aid use is a marker for educational attainment and/or high income, which is an underappreciated variable affecting mortality. Since hearing aids are costly and rarely covered by insurance in the United States, perhaps the causal variable for the survival advantage wasn’t hearing aids, but the ability to afford them?
After reading the scientific article, I learned that NHANES collected information about income, smoking status and other variables that might affect mortality. Three analyses were done: one without adjustments, one that included the income variable and the final one that included variables that might affect longevity, like smoking. The effect of wearing hearing aids held up in all three analyses, although the correlation was lower when additional variables were included.
As the accompanying editorial states, other research studies trying to assess whether wearing hearing aids reduce mortality have found mixed results, so more research is needed. The current report is merely a correlation, based on a secondary analysis of data collected for another purpose. As this article in the National Library of Medicine notes, “SDAs [secondary data analyses] are inherently limited by the inability to definitively examine causality given their retrospective nature.”
I think it’s much better to avoid the need for hearing aids altogether. If something sounds loud, it’s too loud and your auditory health is at risk. Turn down the volume, use hearing protection or leave the noisy environment. If you do this, your ears should last a lifetime, and you shouldn’t ever need hearing aids.