David G Loughrey1,2, Michelle E Kelly1,3, George A Kelley4, Sabina Brennan1, Brian A Lawlor1,2,5. 1. NEIL (Neuro Enhancement for Independent Lives) Programme, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland. 2. School of Medicine, Trinity College Dublin, Dublin, Ireland. 3. Department of Psychology, National University of Ireland Maynooth, Kildare, Ireland. 4. Meta-Analytic Research Group, School of Public Health, Department of Biostatistics, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown. 5. Mercer's Institute for Successful Ageing, St James Hospital, Dublin, Ireland.
Abstract
Importance: Epidemiologic research on the possible link between age-related hearing loss (ARHL) and cognitive decline and dementia has produced inconsistent results. Clarifying this association is of interest because ARHL may be a risk factor for outcomes of clinical dementia. Objectives: To examine and estimate the association between ARHL and cognitive function, cognitive impairment, and dementia through a systematic review and meta-analysis. Data Sources and Study Selection: A search of PubMed, the Cochrane Library, EMBASE, and SCOPUS from inception to April 15, 2016, with cross-referencing of retrieved studies and personal files for potentially eligible studies was performed. Keywords included hearing, cognition, dementia, and Alzheimer disease. Cohort and cross-sectional studies published in peer-reviewed literature and using objective outcome measures were included. Case-control studies were excluded. Data Extraction and Synthesis: One reviewer extracted and another verified data. Both reviewers independently assessed study quality. Estimates were pooled using random-effects meta-analysis. Subgroup and meta-regression analyses of study-level characteristics were performed. Main Outcomes and Measures: Hearing loss measured by pure-tone audiometry only and objective assessment measures of cognitive function, cognitive impairment, and dementia. Cognitive function outcomes were converted to correlation coefficients (r value); cognitive impairment and dementia outcomes, to odds ratios (ORs). Results: Forty studies from 12 countries met our inclusion criteria. Of these, 36 unique studies with an estimated 20 264 unique participants were included in the meta-analyses. Based on the pooled maximally adjusted effect sizes using random-effects models, a small but significant association was found for ARHL within all domains of cognitive function. Among cross-sectional studies, a significant association was found for cognitive impairment (OR, 2.00; 95% CI, 1.39-2.89) and dementia (OR, 2.42; 95% CI, 1.24-4.72). Among prospective cohort studies, a significant association was found 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 disease (OR, 1.69; 95% CI, 0.72-4.00). In further analyses, study, demographic, audiometric, and analyses factors were associated with cognitive function. Vascular dysfunction and impaired verbal communication may contribute to the association between hearing loss and cognitive decline. Conclusions and Relevance: Age-related hearing loss is a possible biomarker and modifiable risk factor for cognitive decline, cognitive impairment, and dementia. Additional research and randomized clinical trials are warranted to examine implications of treatment for cognition and to explore possible causal mechanisms underlying this relationship.
Importance: Epidemiologic research on the possible link between age-related hearing loss (ARHL) and cognitive decline and dementia has produced inconsistent results. Clarifying this association is of interest because ARHL may be a risk factor for outcomes of clinical dementia. Objectives: To examine and estimate the association between ARHL and cognitive function, cognitive impairment, and dementia through a systematic review and meta-analysis. Data Sources and Study Selection: A search of PubMed, the Cochrane Library, EMBASE, and SCOPUS from inception to April 15, 2016, with cross-referencing of retrieved studies and personal files for potentially eligible studies was performed. Keywords included hearing, cognition, dementia, and Alzheimer disease. Cohort and cross-sectional studies published in peer-reviewed literature and using objective outcome measures were included. Case-control studies were excluded. Data Extraction and Synthesis: One reviewer extracted and another verified data. Both reviewers independently assessed study quality. Estimates were pooled using random-effects meta-analysis. Subgroup and meta-regression analyses of study-level characteristics were performed. Main Outcomes and Measures: Hearing loss measured by pure-tone audiometry only and objective assessment measures of cognitive function, cognitive impairment, and dementia. Cognitive function outcomes were converted to correlation coefficients (r value); cognitive impairment and dementia outcomes, to odds ratios (ORs). Results: Forty studies from 12 countries met our inclusion criteria. Of these, 36 unique studies with an estimated 20 264 unique participants were included in the meta-analyses. Based on the pooled maximally adjusted effect sizes using random-effects models, a small but significant association was found for ARHL within all domains of cognitive function. Among cross-sectional studies, a significant association was found for cognitive impairment (OR, 2.00; 95% CI, 1.39-2.89) and dementia (OR, 2.42; 95% CI, 1.24-4.72). Among prospective cohort studies, a significant association was found 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 disease (OR, 1.69; 95% CI, 0.72-4.00). In further analyses, study, demographic, audiometric, and analyses factors were associated with cognitive function. Vascular dysfunction and impaired verbal communication may contribute to the association between hearing loss and cognitive decline. Conclusions and Relevance: Age-related hearing loss is a possible biomarker and modifiable risk factor for cognitive decline, cognitive impairment, and dementia. Additional research and randomized clinical trials are warranted to examine implications of treatment for cognition and to explore possible causal mechanisms underlying this relationship.
Authors: Jacobijn Gussekloo; Anton J M de Craen; Charlène Oduber; Martin P J van Boxtel; Rudi G J Westendorp Journal: Am J Geriatr Psychiatry Date: 2005-09 Impact factor: 4.105
Authors: Clara Kurniawan; Rudi G J Westendorp; Anton J M de Craen; Jacobijn Gussekloo; Jan de Laat; Eric van Exel Journal: Neurobiol Aging Date: 2012-04-28 Impact factor: 4.673
Authors: Nicole M Armstrong; Yang An; Luigi Ferrucci; Jennifer A Deal; Frank R Lin; Susan M Resnick Journal: J Gerontol A Biol Sci Med Sci Date: 2020-02-14 Impact factor: 6.053
Authors: Justin S Golub; Adam M Brickman; Adam J Ciarleglio; Nicole Schupf; José A Luchsinger Journal: J Gerontol A Biol Sci Med Sci Date: 2020-02-14 Impact factor: 6.053
Authors: Jan Löhler; Mario Cebulla; Wafaa Shehata-Dieler; Stefan Volkenstein; Christiane Völter; Leif Erik Walther Journal: Dtsch Arztebl Int Date: 2019-04-26 Impact factor: 5.594
Authors: Jennifer A Deal; Nicholas S Reed; Alexander D Kravetz; Heather Weinreich; Charlotte Yeh; Frank R Lin; Aylin Altan Journal: JAMA Otolaryngol Head Neck Surg Date: 2019-01-01 Impact factor: 6.223