Dichotic Digits Test Performance Across the Ages: Results From Two Large Epidemiologic Cohort Studies.

OBJECTIVES: The Dichotic Digits test (DDT) has been widely used to assess central auditory processing but there is limited information on observed DDT performance in a general population. The purpose of the study was to determine factors related to DDT performance in a large cohort spanning the adult age range. DESIGN: The study was cross-sectional and subjects were participants in the Epidemiology of Hearing Loss Study (EHLS), a population-based investigation of age-related hearing loss, or the Beaver Dam Offspring Study (BOSS), a study of aging in the adult offspring of the EHLS members. Subjects seen during the 4th EHLS (2008 to 2010) or the 2nd BOSS (2010 to 2013) examination were included (N = 3655 participants [1391 EHLS, 2264 BOSS]; mean age = 61.1 years, range = 21 to 100 years). The free and right ear-directed recall DDTs were administered using 25 sets of triple-digit pairs with a 70 dB HL presentation level. Pure-tone audiometric testing was conducted and the pure-tone threshold average (PTA) at 0.5, 1, 2, and 4 kHz was categorized using the worse ear: no loss = PTA ≤ 25 dB HL; mild loss = 25 < PTA ≤ 40 dB HL; moderate or marked loss = PTA > 40 dB HL. Cognitive impairment was defined as a Mini-Mental State Examination score < 24 (maximum = 30) or a self- or proxy-reported history of dementia or Alzheimer's disease. Demographic information was self-reported. General linear models were fit and multiple linear regression was performed. RESULTS: The mean total free recall DDT score was 76.7% (range = 21.3 to 100%). Less than 10% of the participants had a total free recall score below 60% correct. The mean right ear-directed recall score was 98.4% with 69% of the participants scoring 100% and another 15.5% scoring 98.7% (1 incorrect digit). In multivariable modeling of the total free recall scores, the predicted mean free recall score was 1 percentage point lower for every 5-year increase in age, 2.3 percentage points lower in males than females, 8.7 percentage points lower in participants with less than a high school degree than in those with college degrees, 6.8 percentage points lower in participants with a moderate or marked hearing loss compared with no hearing loss, and 8.3 percentage points lower in participants with cognitive impairment compared with those without cognitive impairment. These 5 factors were independently and significantly related to performance and accounted for 22.7% of the total variability in free recall scores. CONCLUSIONS: Substantial variation in the total free recall DDT scores but very little variation in the right ear-directed recall DDT scores was observed. Age, sex, education, hearing loss severity, and cognitive impairment were found to be significantly related to DDT scores but explained less than 25% of the total variability in total free recall scores. The right ear-directed recall DDT by itself may not be of benefit in assessing central auditory processing in a general population because of its limited variability but further evaluation of factors potentially related to free recall DDT variability may prove useful.

Cadmium, obesity, and education, and the 10-year incidence of hearing impairment: The beaver dam offspring study.

OBJECTIVES/HYPOTHESIS: To determine the 10-year incidence of hearing impairment (HI) and associated risk factors in the Beaver Dam Offspring Study (BOSS; 2004-present), a large middle-aged cohort followed for 10 years. STUDY DESIGN: Prospective cohort study. METHODS: Hearing thresholds were measured at baseline (2005-2008) and 5- (2010-2013) and 10-year (2015-2017) follow-up examinations. HI was defined as a pure-tone average >25 dB HL in either ear. BOSS participants free of HI at baseline with at least one follow-up examination (N = 2,065) were included. Potential risk factors evaluated included cardiovascular measures, health history, lifestyle factors, inflammatory markers, vitamins D and B12, lead, and cadmium. RESULTS: Participants were 21 to 79 years (mean age = 47.9 years) at baseline. The 10-year cumulative HI incidence was 17.4% (95% confidence interval [CI]: 15.7-19.2) and was twice as likely in men (24.4%, 95% CI: 21.5-27.7) than in women (12.2%, 95% CI: 10.3-14.3). In a multivariable adjusted model, age (hazard ratio [HR] = 1.48, 95% CI: 1.38-1.59, per 5 years), male sex (HR = 2.47, 95% CI: 1.91-3.18), less than a college education (HR = 1.35, 95% CI: 1.02-1.79), body mass index (HR = 1.03, 95% CI: 1.01-1.05, per kg/m2 ), and higher cadmium levels (HR = 1.42, 95% CI: 1.05-1.92, quintile 5 vs. quintiles 1-4) were associated with the 10-year cumulative incidence of HI. There was no association between high lead levels, vitamins D or B12, and 10-year incidence of HI. CONCLUSIONS: In addition to age and sex, obesity, education, and blood cadmium levels were associated with increased incidence of HI. These prospective results add to evidence that age-related HI is a multifactorial preventable disorder. LEVEL OF EVIDENCE: 2b Laryngoscope, 130:1396-1401, 2020.

Notched audiograms and noise exposure history in older adults.

OBJECTIVE: Using data from a population-based cohort study, we compared four published algorithms for identifying notched audiograms and compared their resulting classifications with noise exposure history. DESIGN: Four algorithms: (1) , (2) , (3) , and (4) were used to identify notched audiograms. Audiometric evaluations were collected as a part of the 10-yr follow-up examinations of the Epidemiology of Hearing Loss Study, in Beaver Dam, WI (2003-2005, N = 2395). Detailed noise exposure histories were collected by interview at the baseline examination (1993-1995) and updated at subsequent visits. An extensive history of occupational noise exposure, participation in noisy hobbies, and firearm usage was used to evaluate consistency of the notch classifications with the history of noise exposure. RESULTS: The prevalence of notched audiograms varied greatly by definition (31.7, 25.9, 47.2, and 11.7% for methods 1, 2, 3, and 4, respectively). In this cohort, a history of noise exposure was common (56.2% for occupational noise, 71.7% for noisy hobbies, 13.4% for firearms, and 81.2% for any of these three sources). Among participants with a notched audiogram, almost one-third did not have a history of occupational noise exposure (31.4, 33.0, 32.5, and 28.1% for methods 1, 2, 3, and 4, respectively), and approximately 11% did not have a history of exposure to any of the three sources of noise (11.5, 13.6, 10.3, and 7.6%). Discordance was greater in women than in men. CONCLUSIONS: These results suggest that there is a poor agreement across existing algorithms for audiometric notches. In addition, notches can occur in the absence of a positive noise history. In the absence of an objective consensus definition of a notched audiogram and in light of the degree of discordance in women between noise history and notches by each of these algorithms, researchers should be cautious about classifying noise-induced hearing loss by notched audiograms.

Neuroprotective factors and incident hearing impairment in the epidemiology of hearing loss study.

OBJECTIVE: Hearing impairment (HI) is common in aging adults. Aldosterone, insulin-like growth factor (IGF1), and brain-derived neurotrophic factor (BDNF) have been identified as potentially protective of hearing. The present study aims to investigate these relationships. METHODS: The Epidemiology of Hearing Loss Study is a longitudinal population-based study of aging in Beaver Dam, Wisconsin, that began in 1993. Baseline for the present investigation is the 1998 to 2000 phase. Follow-up exams occurred approximately every 5 years, with the most recent occurring from 2013 to 2016. Hearing was measured by pure-tone audiometry. HI was defined as a pure tone average (PTA) > 25 decibels hearing level in either ear. Change in PTA was the difference between follow-up examinations and baseline. Baseline serum samples were used to measure biomarkers in 2017. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated to assess the effect of biomarker levels in the lowest quintile (Q1) versus the highest (Q5) on incident HI and PTA change. RESULTS: There were 1,088 participants (69.3% women) at risk of HI included in analyses. The mean baseline age was 63.8 years (standard deviation = 7.0). The 16-year incidence of HI was 54.9% and was higher in men (61.1%) than women (52.1%). In age- and sex-adjusted models, aldosterone (HR = 1.06, 95% CI = 0.82-1.37), IGF1 (HR = 0.92, 95% CI = 0.71-1.19), and BDNF (HR = 0.86, 95% CI = 0.66-1.12) levels were not associated with risk of HI. PTA change was similarly not affected by biomarker levels. CONCLUSION: Aldosterone, IGF1, and BDNF were not associated with decreased risk of age-related hearing loss in this study. LEVEL OF EVIDENCE: 2b Laryngoscope, 129:2178-2183, 2019.

Sensorineural Impairments, Cardiovascular Risk Factors, and 10-Year Incidence of Cognitive Impairment and Decline in Midlife: The Beaver Dam Offspring Study.

BACKGROUND: Sensorineural impairments and cardiovascular risk factors (CVRF) and disease (CVD) in midlife may be important predictors of future cognitive health, but longitudinal studies that include multiple sensorineural measures in middle-aged adults are lacking. METHODS: Hearing, vision, and olfaction, and CVRF and CVD were measured at the Beaver Dam Offspring Study baseline (2005-2008) examination. The Mini-Mental State Examination and Trail Making Tests A and B were administered at all phases and additional cognitive function measures were obtained at 5 (2010-2013) and 10 years (2015-2017). Cox proportional hazards models were used to evaluate associations between baseline sensorineural impairments, CVRF, CVD, and 10-year cumulative incidence of cognitive impairment and decline. RESULTS: There were 2,556 participants (22-84 years) without cognitive impairment at baseline and data from at least one follow-up. In a multivariable model including age, sex, education, and head injury, visual impairment (hazard ratio = 2.59, 95% confidence interval = 1.34, 5.02), olfactory impairment (hazard ratio = 3.18, 95% confidence interval = 1.53, 6.59), CVD (hazard ratio = 2.37, 95% confidence interval = 1.24, 4.52), and not consuming alcohol in the past year (hazard ratio = 2.21, 95% confidence interval = 1.16, 4.19) were associated with the 10-year cumulative incidence of cognitive impairment. Current smoking and diabetes were associated with increased risk, and exercise with decreased risk, of 10-year decline in cognitive function. CONCLUSIONS: Visual and olfactory impairments, CVRF, and CVD were associated with the 10-year cumulative incidence of cognitive impairment and decline in middle-aged adults. Identifying modifiable factors associated with cognitive decline and impairment in midlife may provide opportunities for prevention or treatment and improve cognitive health later in life.

An Epidemiologic Study of the Association between Free Recall Dichotic Digits Test Performance and Vascular Health.

BACKGROUND: Associations between vascular health-related factors and hearing loss defined using audiometric pure-tone thresholds have been found. Studies have not focused on a potential relationship between vascular health-related factors and central auditory processing. PURPOSE: The aim of this study was to evaluate, on a population level, the relationship of vascular health-related factors with central auditory function. RESEARCH DESIGN: A cross-sectional, population study. STUDY SAMPLE: Subjects were participants in the Epidemiology of Hearing Loss Study (EHLS) or the Beaver Dam Offspring Study (BOSS)-prospective studies of aging and sensory loss. BOSS participants were the adult offspring of participants in the EHLS. Participants who completed the Dichotic Digits Test (DDT) during the fourth examination period of the EHLS (2008-2010) or the second examination period of the BOSS (2010-2013) were included (n = 3,655, mean age = 61.1 years). DATA COLLECTION AND ANALYSIS: The DDT-free recall test was conducted using 25 sets of triple-digit pairs at a 70 dB HL presentation level. The total number of correctly repeated digits from the right and left ears was converted to a percentage correct and used as an outcome. The percentage correct in the left ear was subtracted from the percentage correct in the right ear and used as an outcome. Vascular health-related measures obtained during the examination included blood pressure, mean carotid intima-media thickness, femoral pulse wave velocity (PWV), hemoglobin A1C, and non-high-density lipoprotein (HDL) cholesterol, and, in the EHLS participants, C-reactive protein and interleukin-6. Information on vascular health-related history and behaviors was self-reported. General linear modeling produced estimates of the age- and sex-adjusted least squares means for each vascular factor, and multiple linear regression was used for multivariable modeling of each outcome. RESULTS: After multivariable adjustment, participants with diabetes had a significantly lower (worse) mean DDT-free recall total score (-2.08 percentage points, p < 0.001) than those without diabetes. Participants who exercised at least once per week had a significantly higher (better) mean DDT-free recall total score (+1.07 percentage points, p < 0.01) than those who did not exercise at least once per week. Alcohol consumption was associated with a higher DDT-free recall total score (+0.15 percentage points per +25 g ethanol, p < 0.01). In multivariable modeling of the right-left ear difference in DDT-free recall scores, participants with a history of cardiovascular disease (CVD) or higher PWV demonstrated significantly larger differences (CVD: +3.11 percentage points, p = 0.02; PWV: +0.36 percentage points per 1 m/sec, p < 0.01). Higher levels of non-HDL cholesterol were associated with smaller right-left ear differences (-0.22 percentage points per 10 mg/dL, p = 0.01). Adjustment for handedness did not affect the results. CONCLUSIONS: Vascular health-related factors may play a role in central auditory function.

Association Between Cystatin C and 20-Year Cumulative Incidence of Hearing Impairment in the Epidemiology of Hearing Loss Study.

Importance: Hearing impairment (HI) is one of the most common conditions affecting older adults. Identification of factors associated with the development of HI may lead to ways to reduce the incidence of this condition. Objective: To investigate the association between cystatin C, both as an independent biomarker and as a marker of kidney function, and the 20-year incidence of HI. Design, Setting, and Participants: Data were obtained from the Epidemiology of Hearing Loss Study (EHLS), a longitudinal, population-based study in Beaver Dam, Wisconsin. Baseline examinations began in 1993 and continued through 1995, and participants were examined approximately every 5 years, with the most recent examination phase completed in 2015. The EHLS participants with serum cystatin C concentration data and without HI at the baseline examination were included in this study. Main Outcomes and Measures: Participants without HI were followed up for incident HI (pure-tone average of hearing thresholds at 0.5, 1, 2, and 4 kHz >25 dB hearing level in either ear) for 20 years. Cystatin C was analyzed as a biomarker (concentration) and used to determine estimated glomerular filtration rate (eGFRCysC). Discrete-time Cox proportional hazards regression models were used to analyze the association between cystatin C concentration and eGFRCysC and the 20-year cumulative incidence of HI. Results: There were 863 participants aged 48 to 86 years with cystatin C data and without HI at baseline. Of these, 599 (69.4%) were women. In models adjusted for age and sex, cystatin C was associated with an increased risk of developing HI (hazard ratio [HR], 1.20; 95% CI, 1.07-1.34 per 0.2-mg/L increase in cystatin C concentration), but the estimate was attenuated after further adjusting for educational level, current smoking, waist circumference, and glycated hemoglobin (HR, 1.11; 95% CI, 0.98-1.27 per 0.2-mg/L increase in cystatin C concentration). Low eGFRCysC was significantly associated with the 20-year cumulative incidence of HI in both the age- and sex-adjusted model (HR, 1.70; 95% CI, 1.16-2.48; <60 vs ≥60 mL/min/1.73 m2) and the multivariable-adjusted model (HR, 1.50; 95% CI, 1.02-2.22; <60 vs ≥60 mL/min/1.73 m2). Conclusions and Relevance: Reduced kidney function as estimated using cystatin C, but not cystatin C alone, was associated with the 20-year cumulative incidence of HI, suggesting that some age-related HI may occur in conjunction with or as the result of reduced kidney function.

Association of Cadmium and Lead Exposure With the Incidence of Contrast Sensitivity Impairment Among Middle-aged Adults.

Importance: Contrast sensitivity (CS) is an important indicator of visual function that affects daily life, including mobility, visually intensive tasks, safety, and autonomy. Understanding the risk factors for CS impairment could prevent decreases in visual function. Objective: To determine the incidence of and factors associated with CS impairment in a large cohort. Design, Setting, and Participants: The Beaver Dam Offspring Study is an ongoing longitudinal cohort study of aging involving adults in Beaver Dam, Wisconsin. Participants who were free of CS impairment in both eyes at baseline were included (N = 1983). Baseline data collection occurred from June 8, 2005, through August 4, 2008, when the participants ranged from 21 to 84 years of age. Two follow-up examinations occurred at 5-year intervals: one was conducted between July 12, 2010, and March 21, 2013, and the other between July 1, 2015, and November 13, 2017. Data analysis was performed from November 27, 2017, to February 27, 2018. Main Outcomes and Measures: Contrast sensitivity testing was conducted with Pelli-Robson letter sensitivity charts, and incident impairment was defined as a log CS score less than 1.55 in either eye at any follow-up examination. Cadmium and lead levels were measured in whole blood with inductively coupled plasma mass spectrometry. Associations between baseline characteristics and CS impairment incidence were examined using Cox proportional hazard models and quantified as hazard ratios (HRs) with 95% CI. Results: Of the 1983 participants included, 1028 (51.8%) were female and 955 (48.2%) were male, with a mean (SD) age of 48 (9.3) years. The 10-year cumulative incidence of CS impairment was 24.8% (95% CI, 22.9-26.8), similar in women (24.9%) and men (24.6%), and highest in the oldest age group (65-84 years) at 66.3%. In multivariable models, cadmium level in the highest quintile (HR, 1.35; 95% CI, 1.02-1.78), older age (HR, 1.36; 95% CI, 1.25-1.47), larger waist circumference (HR, 1.06; 95% CI, 1.01-1.11), and more plaque sites (1-3 sites: HR, 1.43; 95% CI, 1.07-1.92; 4-6 sites: HR, 2.75; 95% CI, 1.26-6.05) were among the factors associated with increased risk, while male sex (HR, 0.77; 95% CI, 0.60-0.98) and any alcohol consumption (HR, 0.61; 95% CI, 0.43-0.88) were associated with decreased risk. Results were similar when smoking status replaced cadmium exposure in the models. Lead level was not associated with increased risk. Conclusions and Relevance: This study's findings suggest that incident CS impairment was common in the 10-year follow-up, with cadmium, but not lead, exposure associated with increased risk. The associations of diminished CS with other modifiable risk factors found appear to imply that changes in behavior may reduce future incidence of CS impairment.

The impact of tinnitus on quality of life in older adults.

Few population-based data exist to assess the impact of tinnitus on quality of life. As part of the Epidemiology of Hearing Loss Study, self-reported data on tinnitus and quality of life were obtained by interview at the first follow-up examination (1998-2000; N = 2800; ages 53-97 years). The Medical Outcomes Study Short Form Health Survey (SF-36) was used to assess quality of life. Adjusted mean SF-36 scores decreased (worsened) with increasing tinnitus severity (None, Mild, Moderate, Severe) for the Role-Physical, Bodily Pain, Vitality, and Mental Health domains, and the Physical Component Summary scale (F-tests for linear trend, p < .05). Scores tended to be lower for those who first reported tinnitus at the follow-up (five-year incidence of tinnitus) compared to those who reported tinnitus at the baseline and follow-up examinations (prevalent tinnitus). This study documents clear associations between tinnitus and reduced quality of life in this large cohort of older adults.

Generational Differences in the 5-Year Incidence of Age-Related Macular Degeneration.

Importance: Whether a reported decline in the risk of developing age-related macular degeneration (AMD) continued for people born during the Baby Boom years (1946-1964) or later is unknown. These data are important to plan for ocular health care needs in the 21st century. Objectives: To determine whether the 5-year risk for AMD declined by generation and to identify factors that contributed to improvement in risk. Design, Setting, and Participants: Data came from the longitudinal cohort Beaver Dam Eye Study (March 1, 1988, through September 15, 1990, and March 1, 1993, through June 15, 1995) and the Beaver Dam Offspring Study (June 8, 2005, through August 4, 2008, and July 12, 2010, through March 21, 2013). These population-based studies examined residents of Beaver Dam, Wisconsin, aged 43 to 84 years in 1987 through 1988 and their adult offspring aged 21 to 84 years in 2005 through 2008. A total of 4819 participants were at risk for developing AMD based on fundus images obtained at baseline visits. Data were analyzed from February 18, 2016, through June 22, 2017, with additional analyses ending September 22, 2017. Main Outcomes and Measures: Fundus images were graded for AMD using the Wisconsin Age-related Maculopathy Grading System. The incidence of AMD was defined as the presence at the 5-year follow-up examination of pure geographic atrophy or exudative macular degeneration, any type of drusen with pigmentary abnormalities, or soft indistinct drusen without pigmentary abnormalities. Results: Among the 4819 participants, the mean (SD) baseline age of the cohort was 54 (11) years; 2117 were men (43.9%) and 2702 were women (56.1%). The 5-year age- and sex-adjusted incidence of AMD was 8.8% in the Greatest Generation (born during 1901-1924), 3.0% in the Silent Generation (born during 1925-1945), 1.0% in the Baby Boom Generation (born during 1946-1964), and 0.3% in Generation X (born during 1965-1984). Adjusting for age and sex, each generation was more than 60% less likely to develop AMD than the previous generation (relative risk, 0.34; 95% CI, 0.24-0.46). The generational association (relative risk, 0.40; 95% CI, 0.28 to 0.57) remained significant after adjusting for age, sex, smoking, educational attainment, exercise, levels of non­high-density lipoprotein cholesterol and high-sensitivity C-reactive protein, and use of nonsteroidal anti-inflammatory drugs, statins, and multivitamins. Conclusions and Relevance: The 5-year risk for AMD declined by birth cohorts throughout the 20th century. Factors that explain this decline in risk are not known. However, this pattern is consistent with reported declines in risks for cardiovascular disease and dementia, suggesting that aging Baby Boomers may experience better retinal health at older ages than did previous generations.

A longitudinal population study of the impact of cataract extraction on sleep quality.

PURPOSE: To investigate the longitudinal effects of cataract extraction on sleep quality in two discrete population cohorts. METHODS: 301 participants who had senile cataract in both eyes at the baseline examination were selected from two large longitudinal epidemiologic studies of age-related eye disease, hearing, olfaction, and cognition. The participants were divided into two groups: one had cataract surgery (CS) in both eyes, and the other had no cataract surgery (NCS) in either eye by the follow up examination. Cataract was graded from photos or digital images using a standardized protocol. The quality of sleep was assessed using a modified Wisconsin Sleep Cohort Study Questionnaire. The NCS and CS groups were compared as to the change in the number of sleep problems reported from the baseline to the follow-up examination. Systemic co-morbidity data were included as potential confounders, including diabetes mellitus, obesity, hypertension, cerebrovascular disease, thyroid disease, tobacco and alcohol use, and the SF-12 physical component and mental component summary scores. RESULTS: The average (mean±SD) age was 71.0±8.8 years in the NCS (n=237) group and 73.4±9.1 years (n=64) in the CS group. There was no statistically significant difference in the change in the number of sleep problems reported between the NCS and CS groups (mean: -0.068 for NCS and 0.016 for CS, p=0.57). The multivariable linear regression models, when adjusted for confounders, yielded similar results. CONCLUSION: In this longitudinal, community-based population study, we found no significant impact of cataract extraction on sleep quality. Studies of the effect of cataract extraction on sleep should allow a longer follow up to demonstrate sustainability.

Subclinical atherosclerosis and increased risk of hearing impairment.

OBJECTIVE: The study's purpose was to test if subclinical atherosclerosis was associated with the risk of developing HI in a large cohort of middle-aged participants. METHODS: Study subjects were members of the Beaver Dam Offspring Study (BOSS), a longitudinal study of adult children of participants in the population-based Epidemiology of Hearing Loss Study (1993-present). BOSS examinations took place in 2005-2008 (baseline) and 2010-2013 (5-year follow-up). The 5-year incidence of hearing impairment was defined as a pure-tone average (PTA) of thresholds at 0.5, 1, 2 and 4 kHz > 25 dB Hearing Level (dB HL) in either ear at follow-up among participants at risk (baseline PTA in both ears < = 25 dB HL; n = 2436, mean age = 47.7 years). Atherosclerosis was measured as the mean carotid intima-media thickness and the presence of carotid artery plaque. RESULTS: Among the 1984 participants at-risk with a follow-up audiometric examination, the 5-year incidence of hearing impairment was 8.3% (95% Confidence Interval (C.I.) 7.1, 9.5). With multivariable adjustment, carotid intima-media thickness was positively associated with hearing impairment incidence (Relative Risk (RR) = 1.14 per 0.1 mm, 95% C.I. 1.04, 1.24). The number of sites (0-6) with plaque was also positively associated with the incidence of impairment (RR = 1.16 per site, 95% C.I. 1.01, 1.32). CONCLUSION: Atherosclerosis was associated with the 5-year incidence of hearing impairment in this predominantly middle-aged cohort. Interventions targeting atherosclerosis prevention may help to prevent or delay the onset of hearing impairment.

Smoking, central adiposity, and poor glycemic control increase risk of hearing impairment.

OBJECTIVES: To determine associations between smoking, adiposity, diabetes mellitus, and other risk factors for cardiovascular disease (CVD) and the 15-year incidence of hearing impairment (HI). DESIGN: A longitudinal population-based cohort study (1993-95 to 2009-10), the Epidemiology of Hearing Loss Study (EHLS). SETTING: Beaver Dam, Wisconsin. PARTICIPANTS: Participants in the Beaver Dam Eye Study (1988-90; residents of Beaver Dam, WI, aged 43-84 in 1987-88) were eligible for the EHLS. There were 1,925 participants with normal hearing at baseline. MEASUREMENTS: Fifteen-year cumulative incidence of HI (pure-tone average of hearing thresholds at 0.5, 1, 2, and 4 kHz greater than 25 decibels hearing level in either ear). Cigarette smoking, exercise, and other factors were ascertained according to questionnaire. Blood pressure, waist circumference, body mass index, and glycosylated hemoglobin were measured. RESULTS: Follow-up examinations (≥1) were obtained from 87.2% (n=1,678; mean baseline age 61). The 15-year cumulative incidence of HI was 56.8%. Adjusting for age and sex, current smoking (hazard ratio (HR)=1.31, P=.048), education (<16 years; HR=1.35, P=.01), waist circumference (HR=1.08 per 10 cm, P=.02), and poorly controlled diabetes mellitus (HR=2.03, P=.048) were associated with greater risk of HI. Former smokers and people with better-controlled diabetes mellitus were not at greater risk. CONCLUSION: Smoking, central adiposity, and poorly controlled diabetes mellitus predicted incident HI. These well-known risk factors for CVD suggest that vascular changes may contribute to HI in aging. Interventions targeting reductions in smoking and adiposity and better glycemic control in people with diabetes mellitus may help prevent or delay the onset of HI.

Prevalence of sleep problems and quality of life in an older population.

STUDY OBJECTIVES: To determine the prevalence of insomnia traits in a population and the effect of these traits on health-related quality of life. DESIGN: The Epidemiology of Hearing Loss Study is a population-based study in Beaver Dam, Wisconsin. SETTING: Participants were interviewed as part of the 5-year follow-up examination (1998-2000) of the Epidemiology of Hearing Loss Study. Participants were interviewed at the study office in Beaver Dam, WI, by telephone, or at their residence. PARTICIPANTS: 2800 adults aged 53-97 years. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Participants were asked to what extent they experienced difficulty getting to sleep, waking up at night and having a hard time getting back to sleep, and waking up repeatedly during the night for any reason. A response of "often" or "almost always" was coded as positive for an insomnia trait. The SF-36 was administered to assess mental and physical function. Twenty-six percent of the population reported one insomnia trait, 13% reported two, and 10% reported three. All eight domains and the Mental and Physical Component Summary scores of the SF-36 decreased significantly (F-test for linear trend statistically significant at p<0.0001) as the number of reported insomnia traits increased. CONCLUSIONS: These results indicate that symptoms of insomnia are common among older adults and are associated with a decrease in health related quality of life.

Serum cotinine level and incident hearing loss: a case-control study.

BACKGROUND: A growing body of literature suggests an association between cigarette smoking and hearing loss. OBJECTIVE: To assess the relation between levels of serum cotinine, a biomarker of exposure to tobacco smoke, and incident hearing loss. DESIGN: A cross-sectional, incident, case-control study of participants selected from a population-based cohort. SETTING: Testing was conducted at the Beaver Dam Community Hospital, Beaver Dam, Wis. PARTICIPANTS: A total of 197 participants with incident hearing loss and 394 control participants, aged 53 to 75 years, selected from the 2800 participants of the 5-year follow-up examination of the population-based Epidemiology of Hearing Loss Study, 1998-2000. MAIN OUTCOME MEASURE: Incident hearing loss. The incidence of hearing loss was defined as a pure-tone average of thresholds at 500, 1000, 2000, and 4000 Hz greater than 25-dB hearing level in either ear at follow-up among those without hearing loss at baseline. RESULTS: No significant associations were found between serum cotinine levels and incident hearing loss. CONCLUSIONS: These results were not consistent with a previous report, which found cross-sectional associations between prevalent hearing loss and current smoking and environmental tobacco smoke exposure in the home. Longer-term longitudinal studies of smoking and/or serum cotinine levels and the subsequent development of hearing loss may help clarify these associations.

The 5-year incidence and progression of hearing loss: the epidemiology of hearing loss study.

CONTEXT: Hearing impairment affects many older adults, but the incidence is unknown. OBJECTIVE: To determine the 5-year incidence and progression of hearing impairment. DESIGN: A longitudinal, population-based study of adults aged 48 to 92 years at baseline examination. Hearing sensitivity was measured twice, 5 years apart. SETTING: Testing was conducted at the Beaver Dam Community Hospital, Beaver Dam, Wis. PARTICIPANTS: A total of 1636 participants without hearing loss and 1085 participants with hearing loss at the baseline examination in 1993-1995 were reexamined in 1998-2000. MAIN OUTCOME MEASURES: The examinations included otoscopy, screening tympanometry, and tone air- and bone-conduction audiometry. Incidence of hearing impairment was defined as a pure-tone average (PTA) of thresholds at 500, 1000, 2000, and 4000 Hz (PTA 0.5, 1, 2, and 4 kHz) greater than 25 dB HL (hearing level) in either ear at follow-up among those without hearing loss at baseline. Progression was defined as a change of more than 5 dB in the PTA 0.5, 1, 2, and 4 kHz among those with hearing loss at baseline. RESULTS: The 5-year incidence of hearing impairment was 21%. More than half of those with hearing loss at baseline experienced a decline in hearing. Age was an important risk factor for both incidence and progression. Male sex, occupation, and education were associated with the incidence of hearing loss after adjusting for age. CONCLUSIONS: Older adults have a high risk of developing hearing loss. Among those with hearing loss, most experience further declines in hearing sensitivity over time. These data indicate that hearing impairment is an important public health problem and underscore the need for appropriate hearing screening and treatment.

The impact of hearing loss on quality of life in older adults.

PURPOSE: The authors investigate the impact of hearing loss on quality of life in a large population of older adults. DESIGN AND METHODS: Data are from the 5-year follow-up Epidemiology of Hearing Loss Study, a population-based longitudinal study of age-related hearing impairment conducted in Beaver Dam, WI. Participants (N = 2,688) were 53-97 years old (mean = 69 years) and 42% were male. Difficulties with communication were assessed by using the Hearing Handicap for the Elderly-Screening version (HHIE-S), with additional questions regarding communication difficulties in specific situations. Health-related quality of life was assessed by using measures of activities of daily living (ADLs), instrumental ADLs (IADLs) and the Short Form 36 Health Survey (SF-36). Hearing loss measured by audiometry was categorized on the basis of the pure-tone average of hearing thresholds at 0.5, 1, 2, and 4 kHz. RESULTS: Of participants, 28% had a mild hearing loss and 24% had a moderate to severe hearing loss. Severity of hearing loss was significantly associated with having a hearing handicap and with self-reported communication difficulties. Individuals with moderate to severe hearing loss were more likely than individuals without hearing loss to have impaired ADLs and IADLs. Severity of hearing loss was significantly associated with decreased function in both the Mental Component Summary score and the Physical Component Summary score of the SF-36 as well as with six of the eight individual domain scores. IMPLICATIONS: Severity of hearing loss is associated with reduced quality of life in older adults.

Dry eye in the beaver dam offspring study: prevalence, risk factors, and health-related quality of life.

PURPOSE: To estimate dry eye prevalence in the Beaver Dam Offspring Study (BOSS), including a young adult population, and investigate associated risk factors and impact on health-related quality of life. DESIGN: Cohort study. METHODS: The BOSS (2005-2008) is a study of aging in the adult offspring of the population-based Epidemiology of Hearing Loss Study cohort. Questionnaire data on health history, medication use, risk factors, and quality of life were available for 3275 participants. Dry eye was determined by self-report of frequency of symptoms and the intensity of those symptoms. Associations between dry eye and risk factors were analyzed using logistic regression. RESULTS: The prevalence of dry eye in the BOSS was 14.5%: 17.9% of women and 10.5% of men. In a multivariate model, statistically significant associations were found with female sex (odds ratio [OR], 1.68; 95% confidence interval [CI], 1.33-2.11), current contact lens use (OR, 2.01; 95% CI, 1.53-2.64), allergies (OR, 1.59; 95% CI, 1.22-2.08), arthritis (OR, 1.44; 95% CI, 1.12-1.85), thyroid disease (OR, 1.43; 95% CI, 1.02-1.99), antihistamine use (OR, 1.54; 95% CI, 1.18-2.02), and steroid use (OR, 1.54; 95% CI, 1.16-2.06). Dry eye was also associated with lower scores on the Medical Outcomes Study Short Form 36 (ß = -3.9, P < .0001) as well as on the National Eye Institute 25-Item Visual Function Questionnaire (NEI VFQ-25) (ß = -3.4, P < .0001) when controlling for age, sex, and comorbid conditions. CONCLUSIONS: The prevalence of dry eye and its associated risk factors in the BOSS were similar to previous studies. In this study, dry eye was associated with lower quality of life on a health-related quality-of-life instrument and the vision-specific NEI VFQ-25.

Hearing impairment and retirement.

BACKGROUND: Many factors influence the decision to retire including age, insurance, and pension availability along with physical and mental health. Hearing impairment may be one such factor. PURPOSE: The purpose of this study was to compare the 15 yr retirement rate among subjects with and without hearing impairment. RESEARCH DESIGN: Prospective, population-based study. STUDY SAMPLE: Subjects were participants in the Epidemiology of Hearing Loss Study (EHLS), a longitudinal investigation of age-related hearing loss. Participants who were working full- or part-time in 1993-1995 were included (n = 1410, mean age = 57.8 yr). DATA COLLECTION AND ANALYSIS: Data from four EHLS phases (1993-1995, 1998-2000, 2003-2005, and 2009-2010) were analyzed in 2010-2012. Hearing impairment was defined as a pure tone threshold average (at 0.5, 1, 2, and 4 kHz) greater than 25 dB HL in the worse ear. Employment status was determined at each of the four phases. Kaplan-Meier estimates of the cumulative incidence of retirement were calculated, and Cox discrete-time modeling was used to determine the effect of hearing impairment on the rate of retirement. RESULTS: The cumulative incidence of retirement was significantly (p < 0.02) higher in those with a hearing impairment (77%) compared to those without a hearing impairment (74%). After adjustment for age, gender, self-reported health, and history of chronic disease, there was no significant difference in the rate of retirement between those with and without a hearing impairment (hazard ratio [HR] = 0.9, 95% confidence interval (CI) = 0.7, 1.1). Similar results were observed when hearing aid users were excluded, when hearing impairment was based on the better ear thresholds, and when analyses were restricted to those under 65 yr of age and working full-time at baseline. Participants with a hearing impairment were less likely to state that the main reason for retirement was that the time seemed right. CONCLUSIONS: Hearing impairment was found to be associated with a higher rate of retirement, but the association was not independent of the effects of age, gender, and health.

Long-term assessment of systemic inflammation and the cumulative incidence of age-related hearing impairment in the epidemiology of hearing loss study.

BACKGROUND: Although research has linked systemic inflammation to various diseases of aging, few studies have examined the potential role it may play in the development of age-related hearing impairment. METHODS: Among 1,073 participants free of hearing impairment (pure-tone average 0.5, 1, 2, 4kHz ≤ 25 dB HL) in the population-based Epidemiology of Hearing Loss Study (1998-2000), serum C-reactive protein, and interleukin-6 were measured at three time points (1988-1990, 1998-2000, and 2009-2010), and tumor necrosis factor-α was measured at one time point (1998-2000), whereas hearing impairment was measured again in 2003-2005 and 2009-2010 to determine the 10-year cumulative incidence. RESULTS: Inflammatory marker levels from a single time point (1998-2000) were not associated with an increased risk of developing hearing impairment. Associations between long-term serum C-reactive protein levels and incident hearing impairment differed by age (p = .031). Participants less than 60 years with consistently high (>3 mg/L) or increasing levels of serum C-reactive protein over 10 years were nearly two times (hazard ratio: 1.96, 95% confidence interval: 1.19, 3.23) as likely to develop hearing impairment over the subsequent 10-year period, an association not seen in participants more than or equal to 60 years. A statistically significant association (p-trend = .041) was also observed between number of markers in the highest group at baseline and incident hearing impairment in this younger age group. CONCLUSIONS: Associations between long-term serum C-reactive protein levels and incident hearing impairment were observed in the cohort as a whole, but differed significantly by age group, with statistically significant associations observed in adults less than 60 years, participants moving through the peak risk period for hearing impairment over the course of the study.