The Netherlands Longitudinal Study on Hearing (NL-SH) was established in 2006 to address this gap. By following adults with and without hearing loss over many years, the study explores how hearing loss relates to different aspects of daily life. Nearly twenty years of research now show just how wide-ranging its impact can be. Participants are between 18 and 70 years old when they enter the study. They complete an online test that measures how well they understand speech in background noise, along with questionnaires covering hearing, psychosocial well-being, health, work, and the use of hearing devices.
“What we have learned over the years is that hearing loss affects many areas of life,” says Marieke van Wier, senior researcher at Amsterdam UMC and coordinator of the NL-SH. “These include loneliness, anxiety, and depressive symptoms, but also fatigue and effects on work.”
Communication plays a role almost everywhere
One of the first difficulties people with hearing loss notice is that conversations become harder to follow when there is background noise. Van Wier: “Hearing difficulties come up everywhere: at home, in your social interactions, and at work. Whenever sound is involved, your hearing loss comes into play. That can also mean having trouble identifying where sounds are coming from.”
Hearing loss affects every area of a person’s life.
“Hearing loss affects every area of a person’s life.”
The research findings reflect this. Poorer speech understanding in background noise is associated with greater distress, somatization (physical symptoms related to stress or worry), depressive symptoms, and loneliness. The researchers also found differences between age groups. Among adults ages 18–30, poorer speech understanding was associated with greater loneliness; among participants ages 40–49, associations were found with distress, depression, and anxiety.
Listening takes energy
The research also highlights the need for recovery after work. On average, working participants with poorer hearing have a greater need for recovery: they are more tired, find it harder to relax, and feel they need more time to feel well again after a workday. They are also more likely to be unemployed or unable to work due to disability. Among employees who experience little social support at work, poorer hearing was associated with lower self-reported productivity.
According to Van Wier, people do not always realize how much energy listening can take. Hearing usually declines gradually, so the connection with fatigue is not always apparent. “Listening takes energy. Your ears pick up sound, and your brain has to make sense of it. The poorer your hearing, the harder your brain has to work to fill in the missing information and understand what is being said.”
A hearing aid does not eliminate these difficulties entirely. “Many people think that once you get a hearing aid, the problem is solved. That’s not the case. Even with a hearing aid, you still have to make an effort to hear what is being said.” A hearing aid amplifies not only the speaker’s voice but also background noise, so distinguishing between the two remains difficult. In meetings, it can therefore help if people avoid talking over one another and the speaker’s face is visible, allowing people to use visual speech cues.
“Many people think that once you get a hearing aid, the problem is completely solved. That’s not the case.”
Making it possible to stay involved
According to Van Wier, responsibility therefore does not rest solely with the person who has hearing loss. The environment can make a difference, particularly at work. This includes assistive devices and workplace design, as well as how coworkers and managers respond to hearing difficulties. Van Wier:“Right now, responsibility is often placed on the person with hearing loss. I think you need to create a workplace culture where people are asked what they need and are supported in getting it.”
NL-SH findings have helped inform guidelines for occupational physicians. These address the need for recovery, hearing devices, communication strategies, workplace adjustments, and education for coworkers and managers.
Twenty years of follow-up
The long duration of the NL-SH allows researchers to track changes within the same individuals. For example, the study shows that age-related hearing decline accelerates after age 50. A history of smoking is associated with a faster decline. Repeated measurements have also allowed researchers to study, for example, which factors precede the onset of tinnitus.
This year, the study reaches a new milestone. The twenty-year follow-up begins in December, following assessments at baseline and after five, ten, and fifteen years. Meanwhile, new participants continue to enroll.
After nearly twenty years of research, one message has become increasingly clear to Van Wier: hearing loss affects much more than hearing alone. “Hearing loss plays a role in every area of life. Almost everything revolves around communication. It is through communication that the impact can be particularly far-reaching.” In her view, this means focusing not only on preventing hearing damage but also on what people need once they have hearing loss. Van Wier: “If you have hearing loss, an important question is: how can you stay involved and continue to participate in society?”
Read more about NL-SH on the Netherlands Longitudinal Study on Hearing website