title: Diphtheria and hearing loss.
abstract: OBJECTIVE
  To determine if infectious diseases usually experienced in childhood have an effect on hearing ability later in life.
  
  
  METHODS
  The Epidemiology of Hearing Loss Study (N = 3,753) is a population-based study of age-related hearing loss in adults aged 48 to 92 years in Beaver Dam, Wisconsin. As part of this study, infectious disease history was obtained and hearing was tested using pure-tone audiometry. Hearing loss was defined as a pure-tone average of thresholds at 500 Hz, 1,000 Hz, 2,000 Hz, and 4,000 Hz greater than 25 decibels hearing level in either ear.
  
  
  RESULTS
  After adjusting for confounders, only a history of diphtheria (n = 37) was associated with hearing loss (odds ratio [OR] 2.79; 95% confidence interval [CI] 1.05, 7.36). There was no relationship between hearing loss and history of chickenpox, measles, mumps, pertussis, polio, rheumatic fever, rubella, or scarlet fever. Only two participants with a history of diphtheria and hearing loss reported having a hearing loss before age 20.
  
  
  CONCLUSIONS
  Diphtheria in childhood may have consequences for hearing that do not become apparent until later in life. A possible biological mechanism for a diphtheria effect on hearing ability exists: The toxin produced by the Corynebacterium diphtheriae bacteria can cause damage to cranial nerves and therefore may affect the auditory neural pathway. These data may have important implications for areas facing a resurgence of diphtheria cases.
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Wisconsin, 610 N Walnut Street, 460 WARF, Madison, WI 53705, USA. schubert@epi.ophth.wisc.edu
authors.forename: C R
authors.initials: CR
authors.lastname: Schubert
authors.forename: K J
authors.initials: KJ
authors.lastname: Cruickshanks
authors.forename: T L
authors.initials: TL
authors.lastname: Wiley
authors.forename: R
authors.initials: R
authors.lastname: Klein
authors.forename: B E
authors.initials: BE
authors.lastname: Klein
authors.forename: T S
authors.initials: TS
authors.lastname: Tweed
mesh_terms: D000328:Adult; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D003141:Communicable Diseases / Q000150:complications / Q000453:epidemiology; D004165:Diphtheria / Q000150:complications* / Q000453:epidemiology; D004167:Diphtheria Toxin / Q000009:adverse effects; D018450:Disease Progression; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000453:epidemiology* / Q000382:microbiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011304:Presbycusis / Q000453:epidemiology / Q000382:microbiology; D015995:Prevalence; D015203:Reproducibility of Results; D012307:Risk Factors; D012647:Self-Assessment; D013995:Time; D014922:Wisconsin / Q000453:epidemiology
chemical_list: D004167:Diphtheria Toxin