Wednesday, August 28, 2002

Study looks at Alzheimer's, hearing loss

Problem behavior and hearing handicap in patients with Alzheimer's disease and hearing loss were significantly reduced after they began wearing properly fitted hearing aids as part of a unique in-home study conducted by audiologists at the Center for Audiology of the UPMC Eye & Ear Institute and in the Communication Science and Disorders Program at the University of Pittsburgh

The research, published in the Journal of Speech, Language and Hearing Research (April, 1999), further showed that hearing aid treatment for the patient with Alzheimer's disease living at home with a caregiver actually may benefit the caregiver as much as the patient.

"This is the first on-site study of patients with Alzheimer's disease who have hearing loss and are living at home with a caregiver," stated principal investigator Catherine V. Palmer, PhD, assistant professor of communication science and disorders at the university and director of the Center for Audiology.

"We were able to show the positive impact of managing hearing loss with hearing aids by measuring treatment compliance and reduction of problem behaviors as reported by caregivers," she said. "We hope that our research may encourage primary care physicians and audiologists to become more willing to provide accessible hearing assistive care to this patient population and caregivers to become more motivated to seek hearing assistive care.

"Studies and clinical procedures related to Alzheimer's disease largely have ignored the hearing ability of either the patient or caregiver' yet the majority of Alzheimer's disease treatment and investigation depends on communication ability, and caregiver complaints often involve communication-based issues."

Although previous studies showed that more than 60 percent of aging individuals with organic mental syndromes such as Alzheimer's also have impaired hearing, hearing deficits may be the most frequently unrecognized condition of patients with Alzheimer's.

The impairment often is masked by other behavioral symptoms of the disease, and patients may communicate adequately in ideal quiet conditions.

In addition, patients with Alzheimer's traditionally have been considered difficult to test for hearing loss and difficult to manage because of anticipated patient noncompliance.

"Diseases can interact to make a pair of diseases much more disabling than either one alone, and this may be the relationship between Alzheimer's disease and hearing impairment associated with aging," said Dr. Palmer. "Besides its effect on communication, hearing loss has been attributed to eliciting feelings of helplessness, depression, passivity and negativism and has been associated with an accelerated and rapid cognitive decline in subjects with dementia or Alzheimer's disease."

For the study her team of audiologists conducted research entirely in the homes of eight patients with Alzheimer's disease who were hearing impaired and had not been using hearing aids.

Five spouses, two daughters and a son who handled caregiving duties also participated in the study. During the first home visit, the researchers administered hearing tests to the patients similar to those conducted in a clinical setting.

Patients were fitted with the most technologically advanced hearing aids to wear in both ears. Before the devices were given to the patients, the caregivers were trained to identify and document certain hearing-related problem behaviors of patients on a daily basis for one-and-a-half to two-and-a-half months. The researchers made weekly visits to the homes to collect the data.

Documented problem behaviors included the following:

Hearing things that are not there.

Being unable to hear.

Talking nonstop.

Playing the TV/radio too loud.

Repeating questions.

Making negative statements.

Presenting with searching behaviors.

Forgetting recent responses to questions.

After this period the patients began wearing the hearing aids. Caregivers continued to collect daily data on the problem behaviors as well as hearing aid wearing compliance for approximately two months post-treatment.

"We were pleased to find that in each case the caregiver reported one to four problem behaviors ­ such as hearing things that aren't there ­ were significantly reduced," said Dr. Palmer.

In three of the patients, all of the identified problem behaviors were reduced significantly after hearing aid treatment. All but one of the behaviors were reduced in another three, and one behavior was reduced in the remaining two.

When the caregivers were asked if the hearing aid treatment improved the ability of the patients to communicate, six out of eight reported a significant improvement, reported Dr. Palmer. The remaining two said they were less sure.

Regarding patient compliance, each patient wore the hearing aids between five and fifteen hours per day. All but one patient wore them at least seven hours a day by the end of the study.

The work of Dr. Palmer's research team was supported by a grant from the National Association for Alzheimer's Disease.