Use of restorative hearing aids associated with decrease in cognitive decline

The use of restorative hearing devices for hearing loss was associated with a 19% decrease in risk for long-term cognitive decline, as well as improvement in cognitive test scores in the short term, researchers reported in JAMA Neurology.

Hearing loss is associated with cognitive decline, although it is unknown whether restorative hearing devices may help reduce this risk, Brian Sheng Yep Yeo, MBBS, of the Yong Loo Lin School of Medicine at the National University of Singapore, and colleagues wrote.

Researchers sought to evaluate the associations of hearing aids and cochlear implants with cognitive decline and dementia by conducting a meta-analysis of randomized clinical trials and observational studies evaluating the effect of hearing interventions on cognitive function, decline, impairment and dementia in patients with hearing loss.

They screened 3,243 studies and included 19 (15 observational, four trials) in the quantitative analysis.

A meta-analysis of eight studies, which included 126,903 participants, had a follow-up duration ranging from 2 to 25 years and evaluated long-term associations between hearing aid use and cognitive decline. According to researchers, data demonstrated significantly lower hazards of any cognitive decline in hearing aid users compared with those with uncorrected hearing loss (HR = 0.81; 95% CI, 0.76-0.87).

Further analysis of 11 studies, which included 568 participants, revealed a 3% improvement in short-term cognitive test scores following the use of hearing restorative devices (ratio of means = 1.03; 95% CI, 1.02-1.04).

“A cognitive benefit of hearing restorative devices should be further investigated in randomized trials,” Yeo and colleagues wrote.

In a related editorial, Michael W. Denham, MPhil, of the department of otolaryngology and head and neck surgery at New York Presbyterian/Columbia University, and colleagues provided three takeaways from the study.

“First, this meta-analysis provides convincing evidence that hearing aid usage is associated with a considerable risk reduction of cognitive decline,” Denham and colleagues wrote. “While this finding does not prove a causal relationship, it provides convincing evidence that physicians should consider hearing evaluation, which is noninvasive and usually covered by insurance, as part of a standard workup for patients who may be experiencing cognitive decline.”

In addition, Denham and colleagues recommended that future studies examine patients with no baseline cognitive impairment, as well as patients with mild cognitive impairment. In doing so, each group may provide unique risk profiles and trajectories for cognitive decline.

Lastly, Denham and colleagues wrote that Yeo and colleagues’ study is a “testament to the power of pooling studies in meta-analysis.”

They continued, “Most individual studies did not reach statistical significance. However, when the studies were analyzed in aggregate, significance was reached. This result emphasizes the importance of this methodology within our field as well as the utility in standardizing measures of hearing loss and cognitive outcomes across studies of different populations to make conducting meta-analysis easier.”

Reference:

Denham MW, et al. JAMA Neurol. 2022;doi:10.1001/jamaneurol.2022.4155.