• DOI:10.1001/archneurol.2010.362
• Corpus ID: 10575231

Hearing loss and incident dementia.

@article{Lin2011HearingLA,
  title={Hearing loss and incident dementia.},
  author={Frank R Lin and E. Jeffrey Metter and Richard O'Brien and Susan M. Resnick and Alan B. Zonderman and Luigi Ferrucci},
  journal={Archives of neurology},
  year={2011},
  volume={68 2},
  pages={
          214-20
        }
}

• F. Lin, E. Metter, +3 authors L. Ferrucci
• Published 14 February 2011
• Medicine
• Archives of neurology

OBJECTIVE
To determine whether hearing loss is associated with incident all-cause dementia and Alzheimer disease (AD).

DESIGN
Prospective study of 639 individuals who underwent audiometric testing and were dementia free in 1990 to 1994. Hearing loss was defined by a pure-tone average of hearing thresholds at 0.5, 1, 2, and 4 kHz in the better-hearing ear (normal, <25 dB [n = 455]; mild loss, 25-40 dB [n = 125]; moderate loss, 41-70 dB [n = 53]; and severe loss, >70 dB [n = 6]). Diagnosis of incident dementia was made by consensus diagnostic conference. Cox proportional hazards models were used to model time to incident dementia according to severity of hearing loss and were adjusted for age, sex, race, education, diabetes mellitus, smoking, and hypertension.

SETTING
Baltimore Longitudinal Study of Aging.

PARTICIPANTS
Six hundred thirty-nine individuals aged 36 to 90 years.

MAIN OUTCOME MEASURE
Incident cases of all-cause dementia and AD until May 31, 2008.

RESULTS
During a median follow-up of 11.9 years, 58 cases of incident all-cause dementia were diagnosed, of which 37 cases were AD. The risk of incident all-cause dementia increased log linearly with the severity of baseline hearing loss (1.27 per 10-dB loss; 95% confidence interval, 1.06-1.50). Compared with normal hearing, the hazard ratio (95% confidence interval) for incident all-cause dementia was 1.89 (1.00-3.58) for mild hearing loss, 3.00 (1.43-6.30) for moderate hearing loss, and 4.94 (1.09-22.40) for severe hearing loss. The risk of incident AD also increased with baseline hearing loss (1.20 per 10 dB of hearing loss) but with a wider confidence interval (0.94-1.53).

CONCLUSIONS
Hearing loss is independently associated with incident all-cause dementia. Whether hearing loss is a marker for early-stage dementia or is actually a modifiable risk factor for dementia deserves further study.