Early detection and management of hearing loss to reduce dementia risk in older adults with mild cognitive impairment: findings from the treating auditory impairment and cognition trial (TACT)

BACKGROUND: Age-related hearing loss and mild cognitive impairment (MCI) independently increase dementia risk. The Ageing and Cognitive Health Evaluation in Elders randomised controlled trial (RCT) found hearing aids reduce cognitive decline in high-risk older adults with poor hearing. METHODS: This pilot RCT in London memory clinics randomised people with MCI (aged ≥55, untreated hearing loss defined as Pure Tone Average 0.5-4 KHz between 25-70 dB) into two groups. The intervention group received 4 sessions of hearing aid fitting and support. The control group received healthy ageing education and a GP letter recommending audiological referral. Both were followed for 6 months. Primary outcomes were recruitment (feasibility target: 50%; 95% CI: 39%-61%) and retention (feasibility target: 80%; 95% CI: 71%-89%); intervention completion (≥2 visits) and hearing aid use (acceptability target: 80%; 95% CI: 71%-89%) for the intervention group and 50% difference between arms (95% CI: 31%-69%). Secondary outcomes included hearing aid fitting, cognition and other measures. RESULTS: From October 2018 to March 2020, 58 participants were recruited (29 per group, 95% 86%-99%). Twenty-four participants were fitted with hearing aids in the intervention arm, and 6 in the control arm (difference: 62% 42%-82%). At 6 months, retention was 81% 69%-90%. Hearing intervention completion (≥2 visits) was achieved by 24 (83%). Daily hearing aid use was reported by 18 (75%) intervention versus 5 (22%) control participants, a difference of 53% 29%-77%. CONCLUSION: Randomisation of people with MCI to a personalised hearing intervention versus control is feasible. These findings support proceeding to a fully-powered multicentre RCT.