The first two surveys have yielded some highly promising results. Researchers Kramer and Stam discovered that individuals with poorer understanding of speech-in-noise encounter more problems in finding a job. Furthermore, they are usually less well educated and their incomes are lower. "The sense of loneliness is also a huge problem, especially for young people and older individuals with hearing problems," Professor Kramer points out. In the 50-60 age group, however, depressive tendencies pose the primary problem and loneliness is no longer the prime concern. "People's perception of their own situation changes during this phase of life. We need to undertake more studies on this!"
The key question for our healthcare system is: at what age should we have our hearing tested? Data from our study will provide an answer.
Sophia Kramer, Professor
The amount of research undertaken into hearing is still insufficient, as compared to vision. "For instance, an optician can more or less predict the age when you'll need eyeglasses, or when you'll require stronger lenses for your reading glasses," Professor Kramer explains. "We use what are known as trend curves to guide us when assessing levels of hearing ability in different age groups. However, the database for these curves is meager, so the information available is very vague at best. The key question for our healthcare system is: at what age should we have our hearing tested? Data from our study will provide an answer." The hearing ability of respondents in the longitudinal study deteriorated by 0.4 dB during the first five years. But not all age groups are impacted equally, the professor notes: "Up to age 50, the change is linear but then a sudden deterioration sets in. This happens earlier than was expected, and it affects people in the middle of their working lives. We didn't anticipate that!"
Which medical conditions affect the respondents? Participants in the study were also asked about this. PhD student Stam and Sonova researcher Lemke were especially interested in respondents with multiple conditions. "There are indications of a link between vertigo and hearing problems, and also between diabetes and impaired hearing. Moreover, we believe that medication affects hearing ability, for example in case of diabetes," Stam explains. "We need to do more research here: what links are there between conditions that occur simultaneously? What are the underlying mechanisms?" Lemke adds: "In practical hearing loss care, another key priority is to discover how important hearing impairment is to an individual, and to be aware of additional issues that could impede the use of hearing instruments – such as difficulties with vision or sensory problems."
I believe that applied research projects such as this one can yield important data and help us optimize the progression of treatment for the psychosocial consequences of hearing loss.
Mariska Stam, PhD student
Sonova is also sponsoring the third phase of the long-term study project (2015-2018), which will include the next survey of participants. This will mean even closer contact and more interchange between Sonova's Science & Technology department and VU University Medical Center in the years ahead. In January 2015, a new PhD student joined the project team alongside Professor Kramer and Mariska Stam. Stam herself has already paid two visits to Sonova's corporate headquarters on the shores of Lake Zurich. "These were fantastic experiences! It's very interesting to view my questions and research hypotheses in the context of developments that are currently underway in the hearing instrument sector," Stam comments. "And conversely, I believe that applied research projects such as this one can yield important data and help us optimize the progression of treatment for the psychosocial consequences of hearing loss."