[Hearing impairment in senile dementia of Alzheimer's type].

OBJECTIVE

To evaluate the pure tone hearing threshold and word recognition score of senile dementia of the Alzheimer's disease (AD) patients, and to analyze the relationship between hearing loss and the cognition impairment.

METHODS

Pure tone audiometry, word recognition score (WRS), acoustic immittance and auditory brainstem response (ABR) are used to evaluate the auditory function of 43 patients with AD and 50 subjects of the control group. The confounding factors are controlled.

RESULTS

The average age of 43 dementia patients was 72.7 +/- 6.4, and 69.7% was female. Bilateral hearing thresholds are similar in all subjects. All indices but Mini-mental scale of equastionnaire (MMSE) of patients and control group were not statistically different. There was no significant difference in pure tone audiometry (PTA), PTA2 (dB HL, mean +/- s) and WRS (%, mean +/- s) between the two groups (P > 0.05), therefore the hearing threshold of AD group (PTA = 26.3 +/- 8.5, PTA2 = 29.1 +/- 8.7, WRS = 85.5 +/- 15.5) is lower than that of control group (PTA = 23.2 +/- 10.6, PTA2 = 26.2 +/- 11.8, WRS = 87.6 +/- 16.8). No significant difference was found between the two groups in audiometry reliability, acoustic immittance and ABR (P < 0.05).

CONCLUSION

No significant difference was found between the peripheral hearing dysfunction of AD patients and that normal elderly people, i.e., PTA, PTA2 and WRS were not related to MMSE.