Dr. Sumitrajit (“Sumit”) Dhar
Photo by Eileen Molony
Dr. Sumitrajit (“Sumit”) Dhar Photo by Eileen Molony

Dr. Sumitrajit (“Sumit”) Dhar is an expert on hearing loss and the emotional, mental, financial, psychological, and physical effects it has on people, especially older adults. As the Hugh Knowles Professor of Hearing Science in the School of Communication at Northwestern University, he leads the Auditory Research Laboratory at Northwestern, where he and doctoral candidates study hearing, hearing loss, and hearing healthcare.

He recently spoke at a virtual Levy Lecture to a group of several hundred people, many of whom were dealing with hearing loss themselves or experiencing it with a loved one.

Dr. Dhar conveys a sense of wonder and excitement about hearing as he discusses his colleagues’ research as well as his own.  Hearing begins when a fetus is 18 or 19 weeks old. He described research with premature babies, which demonstrated a significant increase in auditory development among babies exposed to the sounds of their mother’s voice and heartbeat, compared to babies exposed to the normal sounds of the neonatal intensive care unit.

Hearing also persists long after many other senses cease functioning, even among unresponsive patients in hospice.

In between gestation and the end of life, a person’s hearing exhibits incredible flexibility and range. When hearing is working at full potential, a person can hear the hum of certain household appliances or voices in another room. It self-regulates, adjusting so that occasional loud noises from a siren or jackhammer do not overwhelm.

Hearing loss is commonplace: 10% of the U.S. population – 48 million Americans – has hearing loss. Hearing loss typically starts slowly between the ages of 20 and 24, with the largest drop occurring between that five-year age range and the ages of 44 to 49. Hearing loss increases as people age, but the rate of loss slows down after age 50.

Fully half of all people over the age of 75 have hearing loss. It is also the third-largest chronic health condition in the country, after heart disease and arthritis. The statistic that Dr. Dhar finds most troubling is one related to hearing healthcare in the United States: only 20% of adults with hearing loss seek treatment.

Research shows that people with hearing loss wait an average of 5 to 7 years before seeking treatment. During this waiting period, the brain is forced to ‘reorganize’ so it can navigate the world with diminished hearing, and the impact of that reorganization is severe.

Hearing loss is expensive; the World Health Organization estimates it costs the United States $133 billion in incremental healthcare expenses.

Untreated hearing loss impacts salaries: when all other factors (race, age, education level, ethnicity, sex) are similar, those without hearing loss make approximately $20,000 more per year compared to those who have untreated hearing loss.

Untreated hearing loss leads to increases in falls, cognitive decline, ability to work, depression, loss of independence, and social isolation.

Hearing loss in midlife is the largest modifiable risk factor associated with dementia.

Fortunately, the news is not all grim. There are many pharmaceutical companies doing research on medical interventions to reverse or stop hearing loss. None is yet ready for release, but Dr. Dhar believes much of the research is promising. He is also a vocal advocate for early testing, intervention, and treatment, ideally for adults in their late 30s or early 40s, as a way of preventing many of the declines mentioned earlier.

The key to reversing the alarming impacts of hearing loss is individual action: Get tested and follow through if the test results indicate treatment is needed. There is no shame in hearing loss, and with hearing aids much smaller and more discreet than even a few years ago, they can hardly be seen – sometimes even by the wearer! Research also shows that for those with hearing loss, brains can improve focus and concentration related to sound as a result of wearing hearing aids steadily for at least six months.

Those interested in finding out more about testing resources in Evanston may check Northwestern’s audiology clinic. An encore presentation of Dr. Dhar’s presentation, including the Q&A period that followed, is available on the Levy Senior Center Foundation’s YouTube channel.