Association between adult-onset hearing loss and dementia biomarkers: A systematic review

Aleksandra B Lasica; Jack Sheppard; Ruan-Ching Yu; Gill Livingston; Nicola Ridgway; Rohani Omar; Anne Gm Schilder; Sergi G Costafreda

doi:10.1016/j.arr.2024.102647

Association between adult-onset hearing loss and dementia biomarkers: A systematic review

Ageing Res Rev. 2024 Dec 31:102647. doi: 10.1016/j.arr.2024.102647. Online ahead of print.

Authors

Aleksandra B Lasica¹, Jack Sheppard², Ruan-Ching Yu³, Gill Livingston⁴, Nicola Ridgway⁵, Rohani Omar⁶, Anne Gm Schilder⁷, Sergi G Costafreda⁸

Affiliations

¹ NIHR University College London Hospitals Biomedical Research Centre, London, UK; The Ear Institute, University College London, 332 Grays Inn Rd, London WC1X 8EE, UK; Division of Psychiatry, University College London, Maple House, 149 Tottenham Court Road, London W1T 7NF, UK. Electronic address: aleksandra.lasica.13@ucl.ac.uk.
² NIHR University College London Hospitals Biomedical Research Centre, London, UK; The Ear Institute, University College London, 332 Grays Inn Rd, London WC1X 8EE, UK; Division of Psychiatry, University College London, Maple House, 149 Tottenham Court Road, London W1T 7NF, UK. Electronic address: jack.sheppard.17@ucl.ac.uk.
³ Division of Psychiatry, University College London, Maple House, 149 Tottenham Court Road, London W1T 7NF, UK. Electronic address: ruan-ching.yu.18@ucl.ac.uk.
⁴ Division of Psychiatry, University College London, Maple House, 149 Tottenham Court Road, London W1T 7NF, UK; North London NHS Foundation Trust, London, 4 St Pancras Way, London NW1 0PE, UK. Electronic address: g.livingston@ucl.ac.uk.
⁵ NIHR University College London Hospitals Biomedical Research Centre, London, UK; The Ear Institute, University College London, 332 Grays Inn Rd, London WC1X 8EE, UK. Electronic address: n.ridgway@ucl.ac.uk.
⁶ NIHR University College London Hospitals Biomedical Research Centre, London, UK; The Ear Institute, University College London, 332 Grays Inn Rd, London WC1X 8EE, UK. Electronic address: rohani.omar@ucl.ac.uk.
⁷ NIHR University College London Hospitals Biomedical Research Centre, London, UK; The Ear Institute, University College London, 332 Grays Inn Rd, London WC1X 8EE, UK; Royal National ENT and Eastman Dental Hospital, University College London Hospitals Trust, 47-49 Huntley St, London WC1E 6DG, UK. Electronic address: a.schilder@ucl.ac.uk.
⁸ Division of Psychiatry, University College London, Maple House, 149 Tottenham Court Road, London W1T 7NF, UK; North London NHS Foundation Trust, London, 4 St Pancras Way, London NW1 0PE, UK. Electronic address: s.costafreda@ucl.ac.uk.

PMID: 39746404
DOI: 10.1016/j.arr.2024.102647

Abstract

Background and objective: People with adult-onset hearing loss (AoHL) are at increased dementia risk. In this study, we explore potential aetiological mechanisms by synthesising the evidence on the association between AoHL and neuropathological, cerebrospinal fluid (CSF), blood and imaging biomarkers of dementia.

Methods: We systematically searched electronic databases from inception to 30 April 2024 for cross-sectional and longitudinal studies, including quantitative data on the association between AoHL and dementia biomarkers. Study quality was assessed with the Mixed Methods Appraisal Tool (MMAT).

Results: Sixty-six studies reporting 63 cross-sectional and 10 longitudinal analyses were included. Twenty-one studies met all MMAT quality criteria. We report a narrative synthesis due to the heterogeneity of the included studies. In CSF-based or blood-based assays or imaging, five out of six cross-sectional analyses found that AoHL was associated with elevated in vivo tau levels, whilst four out of 17 reported a link with elevated in vivo β-amyloid measures. One longitudinal analysis identified an association between AoHL and a steeper increase of CSF tau, but not Aβ₄₂, levels over time. Twenty-five out of 44 cross-sectional and six out of nine longitudinal analyses identified associations between AoHL and grey matter atrophy of the temporal regions, particularly the medial temporal lobe. Studies using other biomarkers had inconsistent findings.

Conclusions: AoHL was usually associated with more temporal regions grey matter atrophy both cross-sectionally and longitudinally, and elevated in vivo tau but not β-amyloid. Increasing atrophy and higher tau, leading to decreased cognitive reserve may be how hearing loss increases dementia risk.

Keywords: Amyloid; Biomarker; Cerebral Atrophy; Dementia; Hearing Loss; Tau.

Publication types

Review