European Journal of Epidemiology

, Volume 34, Issue 2, pp 125–130 | Cite as

Hearing loss, cognitive ability, and dementia in men age 19–78 years

  • Merete OslerEmail author
  • Gunhild Tidemann Christensen
  • Erik Lykke Mortensen
  • Kaare Christensen
  • Ellen Garde
  • Maarten Pieter Rozing


Hearing loss in later life has been associated with risk of dementia. The impact of risk factors for dementia may change during life, and it is unknown whether hearing loss early in midlife represents a risk factor for dementia. We examined whether hearing loss diagnosed in midlife was associated with an increased risk of dementia. A cohort comprising 942,567 Danish men enrolled in the mandatory conscription board examination was followed from conscription (age 19). Cognitive ability was measured at conscription, while hearing loss was ascertained either by physicians diagnosis at conscription or by the Danish National Patient Registry from 1977 to 2016 (ICD-8:388; 389; ICD-10:H90; H91). Differences in cognitive ability in relation to hearing loss at conscription were calculated using t test, while the risk of dementia associated with hearing loss was estimated using Cox regression with adjustment for cognitive ability, education, depression, diabetes, hypertension, and cerebrovascular disease. Men with hearing loss at conscription had about 2 points (corresponding to 0.20 SD) lower mean cognitive score than those without hearing loss. During follow-up, 59,834 men had a hearing loss diagnosis, while 9114 were diagnosed with dementia. Midlife hearing loss was associated with an increased rate of dementia diagnosed before age 60 (adjusted Hazard Ratio (HR) = 1.90 [95% CI 1.59–2.76]) or at a later age (adjusted HR = 1.15 [95% CI 1.06–1.25]). Our study supports the evidence that early identification and correction of hearing loss holds promise for prevention of dementia later in life.


Cognitive ability Hearing loss Dementia Cohort study 



Børge Prien Prøve


Confidence interval


Danish Conscription Database


Danish Conscription Registry


Danish National Patient Registry


Hazard ratio


International Classification of Disease, Eighth Edition


International Classification of Disease, Tenth Edition


Authors' contribution

Merete Osler (MO) conceptualized and designed the study, acquired the data, carried out the analyses and drafted the initial manuscript. Gunhild Tidemann Christensen (GTC) helped to acquire the data. Maarteen Pieter Rozing was involved in the initial conceptualization of the study. All authors critically reviewed and revised the manuscript and approved the final manuscript as submitted. MO and GTC had complete access to the study data that support the publication.


The work was supported by the Danish medical Research Council [Grant Number 09-063599 and 09-069151] and the Velux Foundation [Grant Number 31205], the Jascha Foundation and Doctor Sofus Carl Emil Friis and Olga Doris Friis grant.

Compliance with ethical standards

Conflict of interest



  1. 1.
    Global, regional, and national incidence, prevalence, and years lived with disability for 310 diseases and injuries, 1990–2015: a systematic analysis for the Global Burden of Disease Study 2015. Lancet. 2016;3880053:1545–1602.Google Scholar
  2. 2.
    Livingston G, Sommerlad A, Orgeta V, et al. Dementia prevention, intervention, and care. Lancet. 2017;390:2673–734.CrossRefGoogle Scholar
  3. 3.
    Loughrey DG, Kelly ME, Kelley GA, Brennan S, Lawlor BA. Association of age-related hearing loss with cognitive function, cognitive impairment, and dementia: a systematic review and meta-analysis. JAMA Otolaryngol Head Neck Surg. 2017. Epub 7 December.Google Scholar
  4. 4.
    Lin FR, Albert M. Hearing loss and dementia-who is listing? Aging Ment Health. 2014;18:671–3.CrossRefGoogle Scholar
  5. 5.
    Christensen GT, Skogstad S, Nissen LR, Osler M. Data resource profile: danish conscription registry Data(DCRD). Int J Epidemiol. 2018,
  6. 6.
    Mortensen EL, Reinisch JM, Teasdale TW. Intelligence as measured by the WAIS and a military draft board group test. Scand J Psychol. 1989;30:315–8.CrossRefGoogle Scholar
  7. 7.
    Schmidt M, Schmidt SA, Sandegaard JL, Ehrenstein V, Pedersen L, Sorensen HT. The Danish National Patient Registry: a review of content, data quality, and research potential. Clin Epidemiol. 2015;7:449–90.CrossRefGoogle Scholar
  8. 8.
    Amieva H, Ouvrard C, Meillon C, Rullier L, Dartigues JF. Death, Depression, Disability and Dementia Associated with self-reported hearing problems: a 25-year study. J Gerontol A Biol Sci Med Sci. 2018. Epub 3 January.Google Scholar
  9. 9.
    Hewitt D. Age-related hearing loss and cognitive decline: you haven’t heard the half of it. Front Aging Neurosci. 2017;9:112.CrossRefGoogle Scholar
  10. 10.
    Bunnag C, Prasansuk S, Nakorn AN, et al. Ear diseases and hearing in the Thai elderly population. Part I. A comparative study of the accuracy of diagnosis and treatment by general practitioners versus ENT specialists. J Med Assoc Thai. 2002;85:521–31.Google Scholar

Copyright information

© Springer Nature B.V. 2018

Authors and Affiliations

  1. 1.Center for Clinical Research and Disease PreventionBispebjerg and Frederiksberg HospitalsFrederiksberg, CopenhagenDenmark
  2. 2.Department of Public HealthUniversity of CopenhagenCopenhagenDenmark
  3. 3.Danish Aging Research Center, Institute of Public HealthUniversity of Southern DenmarkOdenseDenmark
  4. 4.Center for Healthy AgingUniversity of CopenhagenCopenhagenDenmark
  5. 5.Department of Clinical GeneticsOdense University HospitalOdenseDenmark
  6. 6.Department of Clinical Biochemistry and PharmacologyOdense University HospitalOdenseDenmark
  7. 7.The Research Unit for General Practice and Section of General Practice, Department of Public HealthUniversity of CopenhagenCopenhagenDenmark

Personalised recommendations