Lin FR, Ferrucci L. Hearing Loss and Falls Among Older Adults in the United States. Arch Intern Med. 2012;172(4):369-371. doi:10.1001/archinternmed.2011.728
Author Affiliations: Department of Otolaryngology–Head and Neck Surgery, Johns Hopkins School of Medicine (Dr Lin), Department of Epidemiology and Center on Aging and Health, Johns Hopkins School of Public Health (Dr Lin), and Longititudinal Studies Section, National Institute on Aging (Dr Ferrucci), Baltimore, Maryland.
Identifying modifiable risk factors for falls in older adults is of significant public health importance. While hearing is not typically considered a risk factor for falls, a recent report of a cohort of older Finnish female twins demonstrated a strong association between audiometric hearing loss and incident falls.1 Possible pathways that could explain this observed association include comcomitant cochlear and vestibular dysfunction, poor awareness of the auditory and spatial environment, or mediation through the effects of hearing loss on cognitive load and shared attention. The latter 2 pathways, which suggest a possible causal pathway between hearing loss and falling, are intriguing because hearing loss is highly prevalent but remains vastly undertreated in older adults.2,3 The objective of this current study was to investigate the cross-sectional association of audiometric hearing loss with self-reported falls in a representative sample of the United States population aged 40 to 69 years who participated in the National Health and Nutritional Examination Survey (NHANES).
The study included participants (age range, 40-69 years) in NHANES (2001-2004) who underwent assessment of audiometric hearing loss and fall history. During this period, a half sample of all adults aged 20 to 69 years underwent audiometric testing, and an interviewer-administered questionnaire on fall history was administered to all adults 40 years and older. The NHANES is an ongoing program of studies that assesses the health and functioning of representative cross-sectional samples of the civilian, noninstitutionalized US population.4
Pure tone audiometry was performed by a trained examiner according to established NHANES protocols (eAppendix). Hearing loss was defined by a speech-frequency pure tone average of thresholds at 0.5, 1, 2, and 4 kHz in the better-hearing ear according to the definition of hearing loss established by the World Health Organization.5 Fall history was ascertained in an interviewer-administered questionnaire. (“Have you had difficulty with falling during the past 12 months?”) Data on demographic variables and medical history were obtained from interviews. Objective vestibular balance testing consisted of test condition 4 of the Modified Romberg Test of Standing Balance on Firm and Compliant Support Surfaces (eAppendix).
Logistic regression was used to analyze the association between hearing loss and self-reported falling after adjustment for age and other covariates. We accounted for the complex sampling design in all analyses by using sample weights according to National Center for Health Statistics guidelines. All analyses were conducted using Stata version 11.1 (StataCorp), and 2-sided P values of less than .05 were considered statistically significant.
From 2001 to 2004, a total of 2017 participants aged 40 to 69 years underwent concurrent assessment of hearing loss and fall history in NHANES (eTable). A hearing loss of greater than 25 dB was prevalent in 14.3% of these participants, and 4.9% of the participants reported falling over the preceding 12 months. We examined the association of hearing loss with having self-reported falls in stepwise logistic regression models. In an unadjusted model, hearing loss was significantly associated with the odds of reported falls. For every 10-dB increase in hearing loss, there was a 1.4-fold (95% CI, 1.3-1.5) increased odds of an individual reporting a fall over the preceding 12 months. Adjustment for demographic factors (age, sex, race, education), cardiovascular factors (smoking, diabetes, hypertension, stroke), and vestibular balance function did not substantially change the magnitude or significance of this association (Table). Restricting the analytical cohort only to those participants with a hearing loss of 40 dB or less (thereby excluding those with a moderate or severe hearing loss) did not affect the magnitude of our results (cf Table).
In this nationally representative study of adults aged 40 to 69 years, greater hearing loss was independently associated with self-reported falls over the preceding 12 months. These results were robust to analyses accounting for multiple confounders, excluding participants with moderate or severe hearing loss, and after adjusting for vestibular balance function. The magnitude of the association of hearing loss with falls is clinically-significant, with a 25-dB hearing loss (equivalent from going from normal to mild hearing loss) being associated with a nearly 3-fold increased odds of reporting a fall over the preceding year.
Our results contribute to the literature examining the association between hearing loss and falls. Our findings are consistent with prior research studies that have used both self-reported6 and audiometric1,7 measures of hearing and have demonstrated that hearing loss is associated with balance function7 and incident falls.1 In contrast, another longitudinal study did not find similar associations.8 Potential factors that may limit the consistency of reported results across studies are variability in how hearing loss is measured, variability in cohort characteristics, and variability in how balance and falls are assessed. For example, in studies in which a hearing screening instrument rather than pure tone audiometry is used,8 any misclassification of hearing loss status by the screening device may bias any observed results toward the null hypothesis.
A number of mechanisms could explain the observed association between hearing loss and falls. There may be a concomitant dysfunction of both the cochlear and the vestibular sense organs given their shared location within the bony labyrinth of the inner ear. Decreased hearing sensitivity may also directly limit access to auditory cues that are needed for environmental awareness. Finally, the association of hearing loss with falls may be mediated through cognitive load and reduced attentional resources. Attentional resources are critical for maintaining postural control,9 and decrements in attentional and cognitive resources imposed by hearing loss10 may impair the maintenance of postural balance in real-world situations and increase the risk of falling.
A key limitation of our study is that our results are based on cross-sectional data rather than on longitudinal trajectories of hearing loss and fall history over time. Our measurement of fall history was also dependent on retrospective self-report. However, our results were generally consistent with other studies,1,6,7 and our results demonstrated a robust association between hearing loss and falls after adjustment for multiple confounders. Further prospective research is needed to determine whether hearing loss is a modifiable risk factor for falls that may be amenable to hearing rehabilitative strategies that remain underused.
Correspondence: Dr Lin, Center on Aging and Health, Johns Hopkins School of Public Health, 2024 E Monument St, Ste 2-700, Baltimore, MD 21205 (firstname.lastname@example.org).
Author Contributions:Study concept and design: Lin and Ferrucci. Analysis and interpretation of data: Lin. Drafting of the manuscript: Lin. Critical revision of the manuscript for important intellectual content: Ferrucci. Statistical analysis: Lin. Obtained funding: Lin. Study supervision: Ferrucci.
Financial Disclosure: None reported.
Funding/Support: This work was supported by the National Institute on Deafness and Other Communication Disorders (K23DC011279) and by a National Institute on Aging Pepper Older Americans Independence Center Research Career Development Award (Dr Lin).