Lewiston, Maine, shooter: Is hearing loss linked to paranoia?

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Hearing loss and psychosis are linked, but the relationship remains murky, experts say.

The question arose in a police report detailing family members’ concerns about Robert Card, the Lewiston gunman. His brother said his paranoia and anger seem to have started around the same time he got hearing aids.

But that doesn’t mean that hearing loss caused the paranoia.

A healthy person who suffers hearing loss won’t suddenly become psychotic as a result, said Dr. Dan G. Blazer, professor emeritus of psychiatry and behavioral sciences at the Duke University School of Medicine. But in someone who already tends toward paranoid thinking, a hearing loss combined with other life events might draw them into psychosis, he said.

“There’s no question that hearing impairment can tip the balance of the scales that lead someone to start acting much more irrationally than they might if they did not have a hearing problem,” Blazer said Tuesday. “It’s an interactive process.”

For example, people who are paranoid “interpret things that are said to them in odd ways,” he said. “Hearing loss means you may be hearing some words in a conversation, but you don’t hear all of them.” In piecing together these conversation fragments, a person might give them an unintended twist.

“If somebody has a tendency toward paranoid thinking, this just adds to it,” Blazer said.

Dr. Dost Öngür, chief of the Division of Psychotic Disorders at McLean Hospital, said in an email that it’s “highly unlikely that hearing loss alone tips an otherwise healthy person into psychosis. It is more likely that hearing loss interacts with other vulnerability factors in a subset of individuals to create psychiatric problems.”

Little is known about the relationship between psychosis and hearing loss.

“All we know is that people with hearing loss especially early in life are more likely to be diagnosed with a psychotic disorder, but whether this is a causal relationship is not clear,” Öngür said. “If it is causal, there may be more than one mechanism.”

Possibly hearing impairment isolates people, contributing to psychiatric problems. Another theory holds that “loss of stimulation to the part of the brain that processes hearing may activate unhealthy brain activity which manifests as psychosis,” Öngür said.

Blazer emphasized that most people with hearing loss do not have mental illness. But hearing difficulties can raise the risk of certain psychiatric disorders.

The three disorders most commonly affected are dementia in the elderly, depression, and psychosis, said Blazer, who in 2018 published a review article about hearing loss and mental illness and who led a 2016 report on hearing health care from the National Academies of Science, Engineering and Medicine.

Hearing loss can contribute to depression by adding to a person’s feeling of isolation. With dementia, “hearing loss may contribute to the biological problems that lead to dementia and cognitive impairment,” Blazer said.

“Hearing health is so important to overall health,” said Barbara Kelley, executive director of the Hearing Loss Association of America, although she had not heard of any connection between hearing loss and psychosis.

One in seven Americans suffer from some degree of hearing impairment, and yet the condition is often invisible or stigmatized as a sign of aging, Kelley said.

But younger people, exposed to loud music and environmental racket, are losing their hearing at growing rates. “Our world is noisier and it’s affecting people and it’s not just older people,” Kelley said.

The World Health Organization warns that more than 1 billion young adults are at risk of permanent hearing loss “due to unsafe listening practices.”

Card was only 40. Although he reportedly had hearing aids, that doesn’t mean he was wearing them.

It’s very common for people who get hearing aids to leave them in the drawer because they don’t work as expected, Kelley said. Hearing loss is permanent, and can’t be corrected the way glasses correct eyesight. Hearing aids help, but it takes time for the brain to adjust, she said.

Hearing aids have been shown to slow the progress of dementia. Could they help with psychosis?

“There are scattered reports of hearing aids improving psychosis symptoms in people who have hearing loss and psychosis,” Öngür said. “But this has not been studied in large definitive studies.”

Many mental health clinicians do not notice hearing problems in the quiet of their offices and are not trained to detect hearing loss, Blazer said.

“One lesson that can be learned is that we need to pay attention to hearing problems in our country more than we are,” he said. “Bad things happen to individuals with hearing loss other than the fact that they can’t hear.”

Report about Maine gunman raises question: Does hearing loss play a role in psychosis?

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