Age-related hearing loss was associated with an increased risk for dementia, cognitive impairment and cognitive decline, according to findings recently published in JAMA Otolaryngology–Head & Neck Surgery. Further study is needed to establish the nature of this link and the role of hearing loss as a potential modifiable risk factor.
"There were several observational studies looking at this association with cognitive decline but results were mixed with some studies reporting a significant association and others reporting either a small or non-significant association. There was also a study published that reported that hearing loss was associated with accelerated decline in brain volume,” David G. Loughery, BA (Hons), of Trinity College in Dublin, told Healio Family Medicine. “This meta-analysis was conducted to clarify whether there was a link in the epidemiological literature using an inclusion criteria to reduce bias.”
Researchers looked at 40 studies with 34,471 participants. Hearing loss was calculated by pure-tone audiometry; dementia, cognitive function and cognitive impairment were also measured.
Loughery and colleagues found that there was a small but significant association for age-related hearing loss across all domains of cognitive function. Specifically, there was a significant link for cognitive impairment (OR = 1.22; 95% CI, 1.09-1.36) and dementia (OR = 1.28; 95% CI, 1.02-1.59) but not for Alzheimer’s disease (OR = 1.69; 95% CI, 0.72-4) in the prospective cohort studies. Also, there was a significant association for dementia (OR = 2.42; 95% CI, 1.24-4.72) and cognitive impairment (OR = 2; 95% CI, 1.39-2.89) in the cross-sectional studies. Additional analysis showed that audiometric, demographic, analyses and study factors were linked with cognitive function. Impaired verbal communication and vascular dysfunction may contribute to the link between hearing loss and cognitive decline.
Loughery discussed how primary care physicians can broach the findings with patients.
“It’s too early for physicians to tell their patients that if their hearing loss is addressed that this will lower their risk of getting dementia,” Loughery told Healio Family Medicine. “A hearing problem can certainly contribute to difficulty with uptake of information and for this reason should be addressed.”
“[Cognitive decline and hearing loss] should be brought up in the context of the known modifiable risk factors that can potentially decrease a person’s risk of getting dementia such as high BP, smoking, low levels of exercise, diabetes, depression and now age-related hearing loss. We believe that it is important that doctors and patients are aware of these modifiable risk factors and while we need more intervention studies to demonstrate that addressing these risk factors, including age-related hearing loss, reduces your risk for dementia, there are enough good reasons already to tackle these risk factors while we await more definitive intervention studies,” he said.
Researchers also wrote that primary care physicians “would benefit from standard guidelines for screening and referring patients with hearing loss.” – by Janel Miller
The authors report no relevant financial disclosures.