Impact of hearing aid use on cognitive function in elderly individuals with hearing loss: a prospective study

OBJECTIVE: To evaluate the cognition and the depressive symptoms of elderly individuals with hearing impairment before and after the use of Hearing Aids (HA), in order to determine whether auditory rehabilitation can influence cognition and mood. METHODS: This is a prospective longitudinal study including elderly participants (>60 years) treated at the Hospital for Rehabilitation of Craniofacial Anomalies (HRAC), University of São Paulo (USP), who had indication for the use of hearing aids for auditory rehabilitation. Prior to HA fitting, tests were applied to assess cognition (Mini-Mental State Exam, verbal fluency test, and clock drawing test), mood (Geriatric Depression Scale), and restriction in daily life activities due to hearing loss (HHIE). These tests were repeated at 6- and 12-months after HA fitting. RESULTS: The study included 56 elderly individuals with a mean age of 73.9-years (±6.9). After 6-months of HA use, a significant increase was observed in the MMSE score ‒ from 23.4 (±4.8) to 24.8 (±4.5) (p = 0.016) ‒ and in the clock test score ‒ from 5.7 (±3.7) to 7.0 (±3.0) (p = 0.016). Participants without initial cognitive decline showed no significant differences. Among those re-evaluated after 12-months, the MMSE score increased from 25.6 (±3.0) to 28.2 (±1.7) (p = 0.001). Verbal fluency improved from 11.0 (±2.7) to 14.3 (±4.2) (p = 0.0013), and the clock test from 7.5 (±2.1) to 8.5 (±1.3) (p = 0.0387). In the subgroup without initial cognitive decline, only verbal fluency showed a statistically significant improvement (p = 0.0031). CONCLUSION: Auditory rehabilitation through HA fitting had a positive impact on cognition in elderly individuals with hearing loss, especially in those who present cognitive decline in the initial tests. LEVEL OF EVIDENCE: According to the Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence, the present study corresponds to Level 3 evidence, being a non-randomized prospective longitudinal study with pre and post intervention assessments.