The effects of improving hearing in dementia.

Background: audiological function is impaired in people with dementia and poor hearing is known to exaggerate the effects of cognitive deficits.

Objective: the objective of this study was to assess the effects of increasing auditory acuity by providing hearing aids to subjects with dementia who have mild hearing loss.

Method: subjects were screened for hearing impairment and fitted with a hearing aid according to standard clinical practice. Measures of cognition and psychiatric symptoms, activities of daily living, and burden on carers were made over 6 months. Hearing aid diaries were kept to record the acceptability of the hearing aids to the subjects.

Results: more than 10% of eligible subjects were excluded as removal of wax restored hearing. Subjects showed a decline in cognitive function, no change in behavioural or psychiatric symptoms over the study period. Forty-two percent of subjects showed an improvement on an independently rated measure of change. The hearing aids were well accepted. Both carers and subjects reported overall reduction in disability from hearing impairment.

Conclusions: all patients with hearing impairment require thorough examination. The presence of dementia should not preclude assessment for a hearing aid as they are well tolerated and reduce disability caused by hearing impairment. Hearing aids do not improve cognitive function or reduce behavioural or psychiatric symptoms. There is evidence that patients improved on global measures of change.