In honor of World Hearing Day today, Apple and the University of Michigan (along with the World Health Organization) have released preliminary data from the Apple Hearing Study announced back in September 2019.
"WHO estimates that there's about 450 million people around the world that have a hearing loss. That's a tremendous public health burden – there's not many other conditions that even approach numbers like that," Rick Nietzel, associate professor of environmental health sciences at the University of Michigan School of Public Health, said in a briefing with journalists. "Chronic environmental noise exposures are now being increasingly linked to things like cardiovascular disease, hypertension, high blood pressure, heart attacks and stroke. These are major killers in America and around the world, and we are increasingly linking them to noise exposure."
The purpose of the study is to collect "high-resolution, long-term data" to answer two questions, Nietzel said. The first question pertains to the association between environmental noise exposure and hearing health. The second is about the aforementioned link to cardiovascular health.
While the study is ongoing, Apple and U of M shared some preliminary results that suggest there's a long way to go to address hearing health in the general population.
Twenty-five percent of study participants have a daily noise exposure over WHO's recommended daily limit, and one in 10 has a weekly headphone exposure over recommended limits.
"That means these folks are potentially at risk after chronic exposure for a noise-induced hearing loss," Nietzel said. "This finding can be a little bit alarming, but it also brings to light actionable intelligence. If we can do a better job of notifying people or warning them when their exposures are at a particularly harmful level, they may be able to modify their behavior in a way that brings that down to a safe level."
While 10% of study participants have been professionally diagnosed with hearing loss, 20% have hearing loss according to Apple's in-app test administered as part of the study. One in four reports tinnitus at least a few times per week.
The study also showed that even when remedies are available, people often don't avail themselves: Three out of four participants with diagnosed hearing loss don't use corrective support, and four in 10 participants (out of the full group) haven't had a professional hearing test in more than a decade.
"Here is a datapoint where we've identified an issue and we know there are steps people can take to help improve their quality of life and minimize the impacts of that hearing loss, but clearly we're not doing a sufficient job as a country of educating people and making them aware that a hearing aid could help you with this condition," Nietzel said. "So here's another educational opportunity."
HOW IT WAS DONE
In the study, conducted through Apple's research app on the iPhone, volunteers can opt in to fill out questionnaires, take digital hearing tests, share headphone audio data and share a variety of vitals data from the Apple Watch. Apple says it has so far collected data from thousands of participants.
The nature of the study does mean the results need to be analyzed in the context of an inherently limited sample, namely people who have iPhones and people who, for whatever reason, chose to opt in to the study.
In its own release, Apple highlighted a number of features in its product suite designed to address hearing loss and improve accessibility, including the Noise app, the Live Listen and Transparency mode features of its AirPod line, and the Made for iPhone program that allows hearing aid users to directly interface their devices with their phones.
ON THE RECORD
"It's not only important for us to continue to study and learn about people's listening behaviors and their exposure patterns, as well as the impacts on their hearing health, but we're also studying people's attitudes on the use of hearing protection," Nietzel said. "So if we can get people to recognize that it's important to protect their hearing, maybe we can steer changes in the right direction in the future."