One or Two Hearing Aids? What a New Study of 275 Adults Found

Shari Eberts: Welcome to This Week in Hearing. I’m Shari Eberts. If you have hearing loss in both ears and have ever talked with an audiologist about hearing aids, you’ve probably heard the recommendation that two hearing aids are better than one. But how strong is the evidence behind that advice? And what if a patient prefers one or, or can only afford one? It’s a question that patients ask all the time, but until now, we haven’t had much strong evidence to guide the answer. A new randomized clinical trial published this year in JAMA Otolaryngology-Head and Neck Surgery set out to fill that gap. And today I’m joined by the study’s lead author, Dr. Sherri Smith. Dr. Smith is an audiologist and a researcher at Duke University who led the clinical trial, and I had the privilege of being part of the research team as the lead patient advocate and co-lead of the stakeholder advisory team. So welcome to This Week in Hearing, Sherri. It’s great to see you.

Sherri Smith: It’s good to see you, Shari. Thank you.

Shari Eberts: Absolutely. So bilateral hearing aids have been the standard recommendation for people with hearing loss in both ears for a long time. So why did that recommendation need to be tested in a randomized clinical trial? And what did we actually know before this study?

Sherri Smith: Yeah, great question, Shari So before I answer that, I just want to think about what is beneficial about having hearing from both ears, right? Right. So bilateral hearing aids are standard because there’s benefit of hearing from both ears. We get timing cues and level cues from the sound coming to both ears, and that’s really helpful for localization. So where sounds are coming from in our environment, It’s helpful for speech understanding in noise, and also kind of the quality and richness and fullness of the sound. So intuitively, it makes sense. If you have hearing loss in both ears and it’s equal, yeah, get two hearing aids. That’s intuitive. But I think 2 reasons are important to consider, and you mentioned one. Mm-hmm. Patients frequently ask the question, do I really need two hearing aids, or is one enough? And so this question comes up clinically very frequently, suggesting that it’s either on patients’ mind or quite important to them. Further, as you mentioned, the study was funded by the Patient-Centered Outcomes Research Institute, or PCORI. And they’re really interested in funding research that matters to patients. And this particular topic was of interest to PCORI because of that reason. It matters to patients. It’s a common question. Also, as you mentioned, the evidence wasn’t very strong. Surprisingly, when we looked at the evidence, it was surprisingly not as strong as you might have thought. And so some of the literature suggests that individuals with more mild hearing loss, as you might see in patients with age-related hearing loss, they don’t have as much bilateral or binaural benefit as people with more significant degrees of hearing loss. Also, the prior studies were older. The randomized clinical trials from the past, they were done in the ’80s and ’90s or even earlier. So the technology used in the studies was older and not relevant to what we use today. The degrees of hearing loss were widely varied and not really focused on the mild degrees of hearing loss, small sample sizes, and the outcomes of interest were pretty variable. So for those reasons, there were gaps in the literature. And all of those studies, there was a significant number of patients who still preferred one hearing aid.

Shari Eberts: Oh, interesting.

Sherri Smith: Very interesting. So there’s a clinical dilemma here, right? We have evidence that’s not very strong, a common question that people are asking, and people are still preferring one at the end of the day, a small portion of them, But those people do exist.

Shari Eberts: Okay, great. So talk about how you created the study. So who participated in that study, what kind of hearing loss they had, and then, you know, how was the randomization done, right? How were people assigned to one group versus the other?

Sherri Smith: Great. So in this study, we did what was called a parallel group design. So we had people assigned to the one hearing aid group and people assigned to the 2 hearing aid group. And we randomly assigned the people to those 2 groups. The people that were in this study, there was 275 individuals who enrolled, which is a very large study. They all had mild to moderate hearing loss, mainly in the higher frequencies, which is consistent with age-related hearing loss. They were 50 and older, and none of them had ever tried hearing aids in the past.

Shari Eberts: Oh, that’s terrific. So just keeping it very real world, it sounds like.

Sherri Smith: That’s right. That’s right. That was a goal, is to keep it very real world.

Shari Eberts: Yep. And as part of that, the participants had to pay for their hearing aids and for the audiology services rather than just, you know, getting them for free as part of the study. So why was that important and what did that add to the study?

Sherri Smith: That’s a great question. Yes, all of the prior studies, the hearing aids were provided to the study participants at no charge. And so that’s not real world, right? When we go to the audiology clinics or the hearing clinics, we have to purchase hearing aids. There is a financial consideration. So for that reason, that was really important to the study because we did want to find out who the benefit of 1 versus 2, but also at the end, what did the patients end up choosing?

Shari Eberts: Right.

Sherri Smith: Right. And part of that choice involves cost. In the study, patients paid for their hearing aids just like they would have normally. So some individuals may have had an insurance benefit that they could apply to the devices and the services, and other individuals had to pay for the devices and services out of pocket. Phonak was our industry partner in this project, but they did provide the study hearing aids at a small discount to patients.

Shari Eberts: So that was an advantage.

Sherri Smith: That was an advantage.

Shari Eberts: Yeah. But clearly when I talk to my friends with hearing loss, one of the main things that we’re always concerned about is price. So what do you— why do you think price is such a consideration? I mean, obviously this is— they say sometimes hearing aids are like the second largest purchase that a person would make after their home or, you know, a car or something like that. Why is that? And should that be the case?

Sherri Smith: Yeah. So hearing aids are— it’s expensive, right? So it’s something that people have to weigh very carefully. People, most people have limited resources, right? So it’s definitely a consideration. And it’s not uncommon for insurance carriers not to provide a benefit. Right. So one thing I would tell consumers who are interested in purchasing hearing aids, ask a lot of questions from the hearing healthcare provider from which you are seeking hearing healthcare. Understand how hearing aids are delivered. Is the cost— does that include the device itself and services? Mm-hmm. If so, are those services for X number of years? What’s provided in those services? What do I get? I think that is the sticker shock that comes with hearing aids, because the services are bundled in, in some cases. Okay. Other clinics separate out the cost of the device from the services, and so you really have a breakdown of what you’re paying for, and it could be that you’ll be surprised that the cost of the hearing aids are lower than you might imagine, depending upon the service delivery model. I would also tell people who are interested in hearing aids to really check your insurance carrier. Call them, see what your benefits are. Maybe you have one, or maybe you have one for the consultation visit, but not for the devices. So really understand what benefits you have. And most providers, or most clinics, do have a financial care coordinator type support person who can help patients understand their benefits. So I would suggest to people, ask a lot of questions.

Shari Eberts: Yeah, no, that’s definitely good advice. Appreciate that. All right, so let’s get to the big question then. So what happened in the study when you compared one hearing aid with two hearing aids? What was different and what was the same? And when it was different, how big was that variation?

Sherri Smith: Yeah, great. So again, we had individuals assigned, randomly assigned to purchase two hearing aids or randomly assigned to purchase 1. And they wore those hearing aids at 3 months, for 3 months. And they came back to the clinic and we measured outcomes. And the primary outcome that we used in this study was self-reported hearing aid benefit. We wanted to hear from people through a standardized questionnaire, how did you feel you benefited from hearing aids. And so on that measure, the change score, how much they benefited, was significantly higher in the bilateral group, as we hypothesized. And that difference between the 2 groups was about 5%. So there was— Right. A little bit more benefit in those who wore two hearing aids than one. But Shari, an important point that I do want to mention is even within the unilateral group, there was improvement. Patients did improve relative to baseline. And baseline, they didn’t have hearing aids at baseline. So we measured how they were doing at baseline and then again 3 months later after they’ve had this treatment. And we looked at the improvement or the benefit. So two hearing aids did provide more benefit, self-perceived benefit on average compared to 1. But it’s important to note that individuals who were assigned to the one hearing aid group did receive benefit.

Shari Eberts: Yeah, that’s so interesting, right? Because it makes it hard sometimes for a person with hearing— with, you know, mild to moderate hearing loss in both ears to try and decide whether to buy one or to buy 2. So what does this study tell them? And what would you say to somebody who can only afford one? Based on this study?

Sherri Smith: Yeah, so I think 2 still dominates. Most people are performing better. They perceive they’re performing better. In addition to benefit, we had some other secondary outcomes, and some of those did also show bilateral hearing aids provided more or higher outcomes compared to 1. So I do believe that patients should still consider 2 compared to one. However, if somebody could only afford one, let’s talk about that.

Shari Eberts: First

Sherri Smith: of all, I would ask the question, do you— don’t assume that you can’t afford just one. Ask those questions that I talked about before. Hearing aids have a variety of technology levels, just like if you’re going shopping for a car, you can get a base model, a mid-level model, and then the high-end fancy model with all the bells and whistles. Hearing aids are the same. So if you’re really interested in two hearing aids and you think you can only afford one, maybe ask the provider, could I have 2, but maybe at a lower entry-level technology level? What is your service delivery model? So that’s the first thing I would ask patients to think about is, can you really just afford one? Do some investigation and see what you really can afford by talking to different providers to seeing what those options are. If it turns out you can really only afford one, one still provided benefit. So I would really keep that in mind. And at the end of the trial, a significant number of people, about 29% of the patients, picked one. They chose one. So one does provide benefit, and that is a consideration, but 2 did provide more benefit.

Shari Eberts: Okay. No, that’s really interesting. What would you say to somebody who’s about maybe an over-the-counter model because they’re sort of in that mild to moderate setting. And maybe they think, well, I can afford 2 over-the-counter hearing aids, but only 1 professional model. First of all, is that accurate? You know, and how would you talk to them about that type of decision?

Sherri Smith: Yeah, that’s a great question. So over-the-counter hearing aids are designed for those with self-perceived mild to moderate hearing loss. Who do not have any red flags, no children. We’re talking adults. And I think it’s a viable option for some individuals, those individuals who are technologically savvy enough to fit the hearing aids or can get support to fit the hearing aids on themselves. And who can really give it a good try. We do see a much, much, much higher return rate on over-the-counter devices compared to prescription fitted hearing aids. But if those over-the-counter devices are fitted well, people can benefit. So I do think it’s a viable option, but for the right candidate.

Shari Eberts: Right. That makes sense. Yeah, there’s definitely a lot of technology and sort of technical things involved with, with hearing aids. But

Sherri Smith: absolutely, yeah, absolutely.

Shari Eberts: So what can audiologists take from the study findings? Does this change how they should approach conversations with patients when they are considering one versus two?

Sherri Smith: Yeah, I think the conversation today is probably the same, right? Bilateral hearing aids are the standard, and audiologists will continue to recommend that. Some recommend that pretty strongly relative to others. So in those instances, I would say if somebody is really preferring one, even if it goes against our standard recommendation, one still provided benefit.

Shari Eberts: Yeah.

Sherri Smith: The other thing I would suggest is inclusion of these patient-reported outcome measures that measured self-perceived benefit. There are ways in which we can look at benefit through behavioral tests and through some other measures, but I am of the stance that I really like to understand what the person is feeling and how they are judging and perceiving the benefit themselves.

Shari Eberts: Mm-hmm.

Sherri Smith: And something like the Abbreviated Profile of Hearing Aid Benefit (APHAB), which was our validated measure that we used in this study, it’s also part of the minimum core data set recommended by the National Academies of Science, Engineering, and Medicine to include in hearing intervention. So inclusion of self-reported measures like that, I think, could help paint a broader picture, a clearer picture of what the actual person is feeling and performing in the clinic. Soon we will have potentially some additional data to report. Not yet, Sherry, soon. You know, we collected a lot of data in that study, right? We did. We did. It was a lot of variables. But we are analyzing analyzing some of those variables to, to see if we can help audiologists guide that conversation better. Are there measures that we might be able to include in the test battery that could give us a little bit more confidence that this person might prefer or choose 1 relative to 2? And candidate measures might be things like hearing handicap or auditory working memory. Don’t quite yet know yet, but more to come on that in the future.

Shari Eberts: Well, I’m eagerly awaiting those results ’cause I think that’s such a— this is such a nuanced thing. And it’s because everybody’s hearing loss is different and everybody lives with their hearing loss in a different way. And so it’s such an individual decision and such an individual benefit or non-benefit in some instances as well. So it really may be that the devil’s in the details here in terms of really making those recommendations. Absolutely.

Sherri Smith: Absolutely.

Shari Eberts: Yeah. All right. So with any research study, there are always limitations, right? That’s just a natural piece of it. So are there any limitations that our listeners should know about for this study?

Sherri Smith: Yeah, there are a few. One is the study design. A randomized clinical trial, we did a rigorous design, right? So very proud of that. But a better design potentially could have been a crossover trial where instead of just that 3-month period, where we assigned 1 or 2, we would have had another period where we also assign the opposite. But we didn’t have that design. So we could have learned more potentially from that design. Another limitation is we only had that 3-month trial. It could be, you know, we would have learned more from a longer period of time, letting people really start to live with those devices in their daily lives. And also a limitation is we really focus on hearing-related outcomes, right? And how the hearing aids were benefiting communication and sound, where, you know, living with hearing loss is more than just communication. It’s also how they, you know, interact with the world, you know, so their social participation, their quality of life. Does it impact— health and other outcome domains more distally. That’s something that would’ve been really interesting to include.

Shari Eberts: Yeah, absolutely. So one of the things that I really liked about the study, because I am a person with hearing loss, is that I loved that the funder, PCORI, as you mentioned, really cares about the patient view. And in fact, they require patient involvement in their study designs. So can you talk a little bit about what impact the patient advisory group had on the study? And were there things maybe that the patients helped to shape that might otherwise have been missed without that element?

Sherri Smith: Yes, I’m so glad that you asked this question, Sherri. I am biased too because I had such an amazing experience including the stakeholder advisory group. So why did I love it so much? It was my first experience having this level of engagement from individuals with hearing loss, from care partners of those with hearing loss, which is important, right? Many people live with others and communicate with others, and it impacts them as well. We heard from audiologists, we heard from otolaryngologists and primary care physicians, industry. So it was very interesting to have all of those different perspectives to inform the study. You were on the study team as an equal person, equal to an investigator. So that was really interesting because you had equal decision-making and conversation about what went into the study. And so we started that from the very beginning and to incorporate this feedback into the study design. What measures should we include that matter to people with hearing loss? Is the APHAB— was that really the best measure to choose? And yes, yes, it was because— that was informed by this group, even down to the details of, you know, what should we put on the website and what the patient-facing materials would be most acceptable to people with hearing loss. But what I found really helpful from this group was launching the study. It was launched during COVID

Shari Eberts: Yeah.

Sherri Smith: None of us knew what was happening during that time, particularly in healthcare and having people come into the building. And what was really probably the most impactful thing is the patients said, we’re not going to restaurants, we’re not going to the grocery, we’re having Instacart come. So what are we doing with trying hearing aids when we’re all at home?

Shari Eberts: Right.

Sherri Smith: So what that did is we actually delayed the launch of the study until the world started opening up a bit. We also were at a time where masking was new. These questionnaires and the measurements that we were asking didn’t include masking, right? And that’s really— we learned during COVID that was really, really difficult for people with hearing loss to have those face masks. Mm-hmm. So our study team designed a questionnaire to understand how masking and social distancing was happening during the study. That way we could interpret the study design with, with that information in mind. And as we went through the study, the world opened up a little bit. So, but we wanted to know, did that impact the study results over time compared to the people who enrolled earlier versus later? And then I loved throughout the study, we would talk to individuals on the team about, you know, recruitment issues, or at the end of the study, what do the results mean? What do these mean to you? So I had such an amazing experience, including the stakeholder advisory team, particularly the patients, that I haven’t written a grant or done a study since without including that group. And particularly the person of interest. So whatever the topic is, the person with that lived experience with that issue is an equal partner on the study team. And you being my first partner as a patient with hearing loss was amazing. So it’s something that moved me and stuck with me since.

Shari Eberts: Well, I love that. And thank you for including me, because as a person with hearing loss, all of us feel like our lived is so critical to be included in anything that is studying hearing loss, right? It’s sort of like nothing about us without us. And so it was really one of my favorite elements of this study. And I’m so glad it was positive for you that you’ve included that even when it’s not necessarily mandated going forward. So that’s a wonderful role model, hopefully for other researchers as well. Yeah. Excellent. Okay, so as we’re wrapping up here, you talked a little bit about this, but what would the ideal next study look like to help us really get closer to answering that question for individual patients?

Sherri Smith: That’s a great question. So I think 2 things pop out. Many things pop out, but probably 2 things that pop out the most for me to investigate in the future is this concept of what is really an improvement that is meaningful to the patient. And one of the questions that came out of this study is there’s this 5% difference between the 2-group versus the 1-group. Is that really clinically meaningful? Some people did improve in a meaningful way on an individual level. At the group level, that’s hard to determine. But more data on what is really important and meaningful to patients. So that, of course, comes out as something that is really important to me to consider in the future. And we can start to do some of that with this data. But so that’s something that we’re starting to look at. And also this question that you’ve also asked before, when somebody is seeking hearing healthcare and trying to make the decision. In the moment, am I going to buy 1 or 2? Is there clinical guidance that could help us predict what to say to that person with more confidence and with stronger data? And we’re not quite there yet. But I do think that that is something that would be really important to be able to answer that question with some more confidence.

Shari Eberts: Excellent. So this has been an important step forward. But there’s always more work to do just to sort of crystallize that information. So excellent. Well, Sherri, thank you so much for joining me and helping to put this research into perspective for people. And I think this study gives both patients and clinicians something they didn’t have before, right? So better evidence to inform the conversation without turning the decision yet into sort of a one-size-fits-all rule. And thank you again for including me on the project. It was really a privilege to bring the patient perspective to such an important study. So thanks so much. to see you.

Sherri Smith: It’s good to see you, Shari. Thank you for having me. I appreciate it.