title: Hearing Impairment Affects Dementia Incidence. An Analysis Based on Longitudinal Health Claims Data in Germany.
abstract: Recent research has revealed an association between hearing impairment and dementia. The objective of this study is to determine the effect of hearing impairment on dementia incidence in a longitudinal study, and whether ear, nose, and throat (ENT) specialist care, care level, institutionalization, or depression mediates or moderates this pathway. The present study used a longitudinal sample of 154,783 persons aged 65 and older from claims data of the largest German health insurer; containing 14,602 incident dementia diagnoses between 2006 and 2010. Dementia and hearing impairment diagnoses were defined according to International Classification of Diseases, Tenth Revision, codes. We used a Kaplan Meier estimator and performed Cox proportional hazard models to explore the effect of hearing impairment on dementia incidence, controlling for ENT specialist care, care level, institutionalization, and depression. Gender, age, and comorbidities were controlled for as potential confounders. Patients with bilateral (HR = 1.43, p<0.001) and side-unspecified (HR = 1.20, p<0.001) hearing impairment had higher risks of dementia incidence than patients without hearing impairment. We found no significant effect for unilateral hearing impairment and other diseases of the ear. The effect of hearing impairment was only partly mediated through ENT specialist utilization. Significant interaction between hearing impairment and specialist care, care level, and institutionalization, respectively, indicated moderating effects. We discuss possible explanations for these effects. This study underlines the importance of the association between hearing impairment and dementia. Preserving hearing ability may maintain social participation and may reduce the burden associated with dementia. The particular impact of hearing aid use should be the subject of further investigations, as it offers potential intervention on the pathway to dementia.
authors.affiliation: German Center for Neurodegenerative Diseases (DZNE), Rostock/Greifswald, Germany.|Rostock Center for the Study of Demographic Change, Rostock, Germany.
authors.forename: Thomas
authors.identifier: http://orcid.org/0000-0001-7649-6936
authors.initials: T
authors.lastname: Fritze
authors.affiliation: German Center for Neurodegenerative Diseases (DZNE), Rostock/Greifswald, Germany.|Department of Psychosomatic Medicine, University Medicine, Rostock, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Teipel
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, University Medicine Rostock, Rostock, Germany.
authors.forename: Attila
authors.initials: A
authors.lastname: Óvári
authors.affiliation: German Center for Neurodegenerative Diseases (DZNE), Rostock/Greifswald, Germany.|Department of Psychosomatic Medicine, University Medicine, Rostock, Germany.
authors.forename: Ingo
authors.initials: I
authors.lastname: Kilimann
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, University Medicine Rostock, Rostock, Germany.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Witt
authors.affiliation: Institute for Sociology and Demography, University of Rostock, Rostock, Germany.|German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.|Max Planck Institute for Demographic Research, Rostock, Germany.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Doblhammer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D003704:Dementia / Q000150:complications / Q000453:epidemiology*; D005260:Female; D005858:Germany / Q000453:epidemiology; D034381:Hearing Loss / Q000150:complications / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007326:Institutionalization; D007348:Insurance, Health; D053208:Kaplan-Meier Estimate; D008137:Longitudinal Studies; D008297:Male; D016016:Proportional Hazards Models; D012306:Risk; D058992:Social Participation