Hearing Aid Use and Cognitive Function
Dawes et al (2015) sought to “clarify the impact of hearing aids on mental health, social engagement, cognitive function, and physical health outcomes in older adults with hearing impairment….” The Epidemiology of Hearing Loss Study (EHLS) in Wisconsin started with 3,753 people who underwent the first round of tests (i.e., “pre-baseline”) in 1993-1995 and included audiometric evaluations as well as a questionnaire on hearing related health, potential risk factors of hearing loss, and self-perceived hearing handicap.
In 1998-2000, 2,800 (of 3,753) participated in the baseline evaluation; 2,395 participated between 2003 and 2005, and 1,812 participated in 2009-2010. Participants were grouped “according to either having obtained hearing aids by the time of the baseline examination and who reported using hearing aids at least some of the time at baseline…” resulting in 96 hearing aid users and 597 non-users. Therefore, the present study included 666 participants who had hearing loss (defined as greater than 40 dB HL loss at 3k/4k in the better ear) at the pre-baseline assessment (1993-1995) and did not have hearing aids at that time. The authors report that the groups were the same with regard to cognition and physical and mental health at baseline. By the time of the first, five-year post-baseline measure, 136 of 666 had died and 37 more were not available for follow-up. By the time of the 11-year evaluation, an additional 167 had died and 13 more were unavailable for follow-up. By the end of the 11-year evaluation, approximately half the HA users and half the non-users had died.
The authors assessed the following at baseline: 5 years pre-baseline, as well as 5 and 11 years post-baseline; hearing impairment (via the Hearing Handicap Inventory for the Elderly Screening), cognition (via the Mini Mental State Exam, Trail Making, Auditory Verbal Learning, Digit Symbol Substitution, Verbal Fluency, Incidence of Cognitive Impairment), as well as physical health, social engagement, and mental health. With regard to demographic measures (age, gender, education, and household income), “there were no significant differences between hearing aid (HA) users and non-users.” Hearing aid users had significantly more hearing loss (39 dB PTA) than non-users (30 dB PTA) and HA users had greater HHIE-S handicaps at pre-baseline and baseline than non-users. All HA users wore their HAs at least “some of the time.” Seventy-three percent of HA users wore HAs every day, 67 percent wore HAs more than 8 hours daily. Nonetheless, the authors report hours of hearing aid use does not necessarily indicate/reflect the benefit received.
Dawes et al summarized that “there is converging evidence from observational, quasi-experimental and RCT studies that hearing aids reduce hearing handicap….” “There is limited and inconsistent evidence for the impact of hearing aids on mental health, physical health, cognitive function, and social engagement….” Dawes et al report that “in the present study, there were no differences in cognitive performance or the incidence of cognitive impairment between hearing aid users and non-users.” They state that “this is not supportive of a robust effect of hearing aid use as being protective against cognitive decline.” “Hearing aids may promote general better healthy, perhaps by reducing hearing handicap and promoting a more active, engaged lifestyle.” Finally, the authors conclude that “in the present study, there was no evidence that hearing aids are effective in promoting perceived mental health, cognitive function, or social engagement in the long term. However, hearing aids may be effective in reducing hearing handicap, and may promote better perceived quality of physical health….”
For More Information, References and Recommendations
Beck DL, Edwards B, Humes LE, Lemke U, Lunner T, Lin FR, Pichora-Fuller MK. (2012) Expert Roundtable: Issues in Audition, Cognition, and Amplification. Hearing Review. September
Beck DL, Edwards B, Fullgrabe C, Saunders G, Galster J, Pittmanm A, Singh G. (2015) Expert Roundtable: Cognition, Audition and Amplification. Hearing Review. September.
Dawes P, Cruickshanks KJ, Fischer ME, Lkein BEK, Klein R, Nondahl DM. (2015) Hearing Aid Use and Long-Term Health Outcomes—Hearing Handicap, Mental Health, Social Engagement, Cognitive Function, Physical Health and Mortality. International Journal of Audiology 54:838-844.