Significant improvement of working memory by cochlear implantation in post-lingual hearing-impaired individuals aged 70 years and older at a 2-year follow-up

Objective:

The aim of the present study was to investigate cognitive abilities in a 2-year follow-up measured in terms of working memory and processing speed after unilateral cochlear implantation (CI) in patients aged 70 years and over with bilateral hearing loss.

Patient and method:

In this prospective study, 14 post-lingual deafened CI candidates, aged 70 years and older (76.7 ± 4.7 years) with unilateral CI were examined over a follow-up period of at least 2 years. Cognitive abilities were assessed by working memory (AG) and processing speed (VG) (Wechsler Adult Intelligence Scale 4th ed., WAIS-IV). Beyond that, speech comprehension (Freiburg monosyllabic Test, 65 dB SPL, adaptive OLSA) and the depression (ADS-L) were analysed.

Results:

The preoperative measurement values of cognitive function increase steadily after 12 and 24 months postoperatively (preop AG: 95.1 ± 9.4, VG: 96.4 ± 13.0, 12 months postoperative AG: 96.4 ± 8.3, VG: 99.9 ± 14.5, 24 months postop AG: 101.7 ± 12.6, VG: 100.6 ± 15.7). After 24 months, there is a significant improvement in the AG (p = 0.5). Speech comprehension improved significantly as well. Depression was at a low level in the elderly population (preoperatively 11.4 ± 6.8).

Conclusion:

The results support the hypotheses and models of current literature discussion whereby certain cognitive functions are influenced by hearing. Improving hearing with CI of hearing-impaired elderly can lead to improving cognitive performance in working memory.

Publication History

Publication Date:
23 April 2019 (online)