Hearing Loss and Risk of Mild Cognitive Impairment and Dementia: Findings from the Singapore Longitudinal Ageing Study

Abstract

Aim: To investigate the associations between hearing loss and prevalent and incident mild cognitive impairment (MCI), dementia and MCI or dementia (all cases). Methods: Cross-sectional and longitudinal analyses of baseline and follow-up data were performed in a population-based cohort. The baseline sample of 2,599 adults aged ≥55 included 1,515 cognitively normal subjects who were followed up to 8 years. Hearing loss at baseline was determined by the whispered voice test, and MCI and dementia by Mini-Mental State Examination screening, Clinical Dementia Rating scale, neurocognitive tests, MRI, and panel consensus diagnosis. Results: Hearing impairment was associated with increased prevalence of dementia (odds ratio = 3.63, 95% confidence interval [CI] 1.16-11.4, p = 0.027) but not MCI alone or all cases of MCI or dementia, adjusted for sex, age, ethnicity, education, central obesity, hypertension, diabetes, dyslipidemia, smoking, alcohol, leisure time activity, cardiac diseases, and depressive symptoms. Among participants who were cognitively normal at baseline, those with hearing impairment were more likely to develop MCI or dementia (hazard ratio [HR] = 2.30, 95% CI 1.08-4.92, p = 0.032). Hearing loss was associated with elevated but statistically nonsignificant estimates of adjusted HR (1.85, 95% CI 0.78-4.40) for incident MCI alone. Conclusions: Hearing loss is independently associated with prevalent dementia and incident MCI or dementia.

Does Treating Hearing Loss in Older Adults Improve Cognitive Outcomes? A Review

“…Although still limited in number, these studies report consistent results, supporting the hypothesis of an increased risk of dementia which remains significant even after statistically accounting for potential confounders such as demographic and/or cardiovascular factors. Such results have been gathered from studies considering hearing loss either with audiometric measures [15,27,28], speech recognition tests [29], or indirect/self-reported measures [30][31][32]. Although most of the studies considered peripheral hearing loss, the link between age-related central auditory processing disorder [33] and cognitive decline and/or dementia has also been reported by two longitudinal studies [34,35].…”

Social determinants of the association among cerebrovascular disease, hearing loss and cognitive impairment in a middle‐aged or older population: Recurrent neural network analysis of the Korean Longitudinal Study of Aging (2014–2016)

“…For instance, several studies report a positive linkage between a pair of cerebrovascular disease, hearing loss and cognitive impairment, which is being affected by age, education, stroke history and vascular disorder (e.g. hypertension, diabetes) . This line of research also suffers from paying attention to only a small set of factors for the association (excluding social determinants, such as family support and social activity) and/or having a cross‐sectional research design (which cannot analyze a causal relationship between the association and its determinants).…”

“…hypertension, diabetes). [7][8][9][10][11][12] This line of research also suffers from paying attention to only a small set of factors for the association (excluding social determinants, such as family support and social activity) and/or having a cross-sectional research design (which cannot analyze a causal relationship between the association and its determinants). Indeed, new methods might be required for the prediction of the association as a set of multiple dependent variables, given that making a prediction over a set of multiple dependent variables is much less accurate and effective than doing so for a single dependent variable.…”

Combined Impact of Telomere Length and Mitochondrial DNA Copy Number on Cognitive Function in Community-Dwelling Very Old Adults

“…Recent studies have suggested that deficits in cognitive function may transition to dementia, and mild cognitive impairment is now considered a risk factor for dementia [3]. Furthermore, cognitive impairment is associated with various age-related conditions [4,5,6]. Although multiple factors including oxidative stress and inflammation play a part in age-related cognitive decline [7,8], the precise mechanism underlying the decline in cognitive function remains unknown.…”