In a highly controlled comparison study, several over-the-counter hearing assistance devices performed almost as well as a conventional hearing aid that cost thousands of dollars more, reports Medpage Today. Three of five selected personal sound amplification products (PSAP) were found to improve speech understanding among participants with mild-to-moderate hearing loss to a degree that was comparable to results obtained with a hearing aid, Nicholas Reed, AuD, of Johns Hopkins School of Medicine, and colleagues say.
The US Congress is currently considering rare, bipartisan legislation that would allow these devices to be marketed as direct-to-consumer products subject to US Food and Drug Administration (FDA) regulation. At present, hearing aids can only be purchased through a licensed hearing specialist. Hearing aids for both ears typically cost around $4,500, while PSAPs cost several hundred dollars or less.
The Over-the-Counter Hearing Aid Act of 2017 is being sponsored in the Senate by Elizabeth Warren (D-Mass) and Charles Grassley (R-Iowa) and in the House by Joseph Kennedy (D-Mass) and Marsha Blackburn (R-Tenn). Reed is quoted in the report as saying that the study findings lend support to the creation of the new regulatory classification for hearing aids.
“Some of these devices did about as well as the hearing aid in our controlled environment, suggesting that some PSAPs are pretty good,” he said. “Perhaps we should support the movement to get these in the hands of more people and to regulate them to improve the quality of the products.”
But Reed emphasised that it is not clear if the hearing improvement observed in the study is achievable in a real-world setting.
The researchers conducted electro-acustic testing on widely sold PSAPs to find the best performing ones, and the devices were fit and adjusted by audiologists to achieve the optimal hearing outcome. “We don’t yet know if people can achieve these results on their own with these devices. This study was truly an efficacy study,” he said.
Between April 2016 and January 2017, the researchers screened adults ages 60 to 85 at a university audiology clinic to recruit a convenience sample for the randomized study. Inclusion criteria included mild to moderate hearing loss (20-55 dB HL; pure-tone average, 500-4000 Hz), no prior amplification use, and no cognitive impairment.
Note that this small, randomised trial suggests that some personal sound amplification products may perform as well as much more costly hearing aids. However, the report says, the study was in a highly controlled environment, and not all available PASPs were tested.
Study participants completed the AZBio sentence-in-noise task, which is a routinely used measure of speech understanding to assess functional hearing. Participants repeated sentences in the presence of background noise under seven different conditions: unaided, with a hearing aid, and with five different PSAPs.
Four of the PSAPs were chosen for the study because they performed well on the electro-acustic testing and one was chosen because it is commonly sold in retail pharmacies, Reed said.
To control for order effects, sentence lists and devices were randomly ordered using a Latin square design balancing first-order carryover effects. Accuracy (percentage of words repeated correctly; range, 0%-100%) was recorded for each condition (20 sentences per condition).
All testing was completed in a calibrated sound booth by an audiologist. To simulate a moderately difficult listening environment, sentences were presented via a speaker at 0° azimuth (directly in front of the participant) at 35 dB HL. Speech babble noise was concurrently presented at a 180° azimuth (directly behind) at 30 dB HL.
The hearing aid chosen for the study was a model that is commonly dispensed in a university audiology clinic. “The same units were tested in each participant, unilaterally fit and adjusted to each participant’s hearing in their better-hearing ear using best-practice verification methods by an audiologist,” the researchers noted.
Linear mixed-effects regression models were used to model the within-participant change in performance with each device.Forty-two people were included in the study (mean age 71.6 years, 67% women).
Among the main findings: the hearing aid and four of the PSAPs improved speech understanding, compared to the unaided condition; the mean unaided accuracy was 76.5% and the hearing aid improved speech understanding accuracy to 88.4% (absolute improvement = 11.9%, 95% CI 9.8-14.0); three of the PSAPs showed improvements that were within five percentage points of the hearing aid (Sound World Solutions CS50+ = 11.0, 95% CI 8.8-13.1; Soundhawk = 10.2, 95% CI 8.0-12.3); Etymotic BEAN = 7.7, 95% CI 5.5-8.9); and speech understanding was poorer with one device than in unaided testing (accuracy 65.3%, -11.2% difference, 95% CI -15.2 to -7.31).
Reed noted that the poor performance of the device that was not chosen for its favorable electroacoustic properties highlights the need for regulation of the products and greater transparency to consumers. “If I had to guess, I would say that more products on the market right now are low quality than high quality,” he said.
Presently, hearing aids can only be purchased in the United States through a licensed professional, with a mean cost of $4700 for 2 hearing aids (uncovered by Medicare).1- 3 According to nationally representative estimates based on 2605 adults from 1999 through 2006, less than 20% of adults with hearing loss report hearing aid use.4 Personal sound amplification products (PSAPs) are less-expensive, over-the-counter devices not specifically labeled for hearing loss treatment, but some are technologically comparable with hearing aids and may be appropriate for mild to moderate hearing loss.1 We compared a sample of these devices with a conventional hearing aid among individuals with mild to moderate hearing loss.
Nicholas S Reed, Joshua Betz, Nicole Kendig, Margaret Korczak, Frank R Lin