Scott D. Nash

The Prevalence of Age-Related Macular Degeneration and Associated Risk Factors

OBJECTIVES To determine the prevalence of age-related macular degeneration (AMD) and to examine how retinal drusen, retinal pigmentary abnormalities, and early AMD are related to age, sex, and other risk factors. PARTICIPANTS A total of 2810 people aged 21 to 84 years participating in the Beaver Dam Offspring Study. METHODS The presence and severity of various characteristics of drusen and other lesions typical of AMD were determined by grading digital color fundus images using the Wisconsin Age-Related Maculopathy Grading System. RESULTS Early AMD was present in 3.4% of the cohort and varied from 2.4% in those aged 21 to 34 years to 9.8% in those aged 65 years or older. In a multivariable model (expressed as odds ratio; 95% confidence interval), age (per 5 years of age, 1.22; 1.09-1.36), being male (1.65; 1.01-2.69), more pack-years of cigarettes smoked (1-10 vs 0, 1.31; 0.75-2.29; >or=11 vs 0, 1.67; 1.03-2.73), higher serum high-density lipoprotein cholesterol level (per 5 mg/dL, 0.91; 0.83-0.998), and hearing impairment (2.28; 1.41-3.71) were associated with early AMD. There were no associations of blood pressure level, body mass index, physical activity level, history of heavy drinking, white blood cell count, hematocrit level, platelet count, serum total cholesterol level, or carotid intimal-medial thickness with early AMD. CONCLUSIONS These data indicate that early AMD is infrequent before age 55 years but increases with age thereafter. Early AMD is related to modifiable risk factors, eg, smoking and serum high-density lipoprotein cholesterol level.

Education, occupation, noise exposure history and the 10-yr cumulative incidence of hearing impairment in older adults

The purpose of this study was to determine the 10-yr cumulative incidence of hearing impairment and associations of education, occupation and noise exposure history with the incidence of hearing impairment in a population-based cohort study of 3753 adults ages 48-92 yr at the baseline examinations during 1993-1995 in Beaver Dam, WI. Hearing thresholds were measured at baseline, 2.5 yr-, 5 yr-, and 10-yr follow-up examinations. Hearing impairment was defined as a pure-tone average (PTA)>25 dB HL at 500, 1000, 2000, and 4000 Hz. Demographic characteristics and occupational histories were obtained by questionnaire. The 10-yr cumulative incidence of hearing impairment was 37.2%. Age (5 yr; Hazard Ratio (HR)=1.81), sex (M vs W; HR=2.29), occupation based on longest held job (production/operations/farming vs others; HR=1.34), marital status (unmarried vs married; HR=1.29) and education (<16 vs 16+yr; HR=1.40) were associated with the 10 yr incidence. History of noisy jobs was not associated with the 10-yr incidence of hearing impairment. The risk of hearing impairment was high, with women experiencing a slightly later onset. Markers of socioeconomic status were associated with hearing impairment, suggesting that hearing impairment in older adults may be associated with modifiable lifestyle and environmental factors, and therefore, at least partially preventable.

The prevalence of hearing impairment and associated risk factors: the Beaver Dam Offspring Study.

OBJECTIVE To estimate the prevalence of hearing impairment (HI) and evaluate the cross-sectional associations of environmental and cardiovascular disease risk factors and HI in middle-aged adults. DESIGN Data were collected as part of the Beaver Dam Offspring Study, an epidemiological cohort study of aging. Hearing impairment was defined as a pure-tone average (0.5, 1.0, 2.0, and 4.0 kHz) greater than 25 db hearing level in either ear. Word recognition in competing message (WRCM) was measured using the Northwestern University No. 6 word list. Questionnaire information about behaviors, environmental factors, and medical history was also collected. PARTICIPANTS The participants (N = 3285) were offspring of participants of the population-based Epidemiology of Hearing Loss Study and ranged in age from 21 to 84 years (mean age, 49 years). RESULTS The prevalence of HI was 14.1%, and the mean (SD) WRCM score was 64% (15%). In a multivariate model, after age, sex, education, and occupational noise were controlled for, a history of ear surgery (odds ratio [OR], 4.11; 95% confidence interval [CI], 2.37-7.15), a larger central retinal venular equivalent (OR, 1.77; 95% CI, 1.20-2.60 [fourth quartile vs first quartile]), and a higher hematocrit percentage (OR, 0.77; 95% CI, 0.63-0.95 [per 5%]) were independently associated with HI. Factors associated with lower WRCM scores were similar but also included mean intima-media thickness (mean difference, -0.63%; 95% CI, -1.06% to -0.19%; P = .005 [per 0.1 mm]) and statin use (mean difference, -2.09%; 95% CI, -3.58% to -0.60%; P = .005). CONCLUSIONS Hearing impairment is a common condition in middle-aged adults. Cardiovascular disease risk factors may be important correlates of age-related auditory dysfunction.

Socioeconomic status and subclinical atherosclerosis in older adults.

OBJECTIVE This study investigated the long-term effects of socioeconomic status (SES) on atherosclerosis. METHODS Data from the Epidemiology of Hearing Loss Study and the Beaver Dam Eye Study (Beaver Dam, WI, 1998-2000), were used to examine adult SES (education, household income, and longest-held job) and childhood SES (household density and parental home ownership at age 13) associations with carotid intima-media thickness (IMT) and carotid plaque in a cohort of 2042 men and women aged 53 to 94 years. RESULTS For education, income, and occupation (women), those in the lowest SES group had statistically larger age-sex-adjusted IMT than those in the highest SES group (<12 vs. >12 years education: 0.92 vs. 0.86 mm respectively, P<0.0001), (<

Long-term Assessment of Systemic Inflammation and the Cumulative Incidence of Age-related Hearing Impairment in the Epidemiology of Hearing Loss Study

10,000 vs. >

Long-Term Variability of Inflammatory Markers and Associated Factors in a Population-Based Cohort

45,000: 0.97 vs. 0.87 mm, P<0.0001), (operator/fabricator/labor vs. manager/professional: 0.89 vs. 0.82 mm, P<0.001). Associations were similar using carotid plaque as the outcome. Participants with low levels of both adult and childhood SES measures had age-sex-adjusted IMT greater than those with persistently high levels of SES (0.93 vs. 0.84 mm, P<0.0001). CONCLUSIONS Measures of SES at two points in the life-span were associated with subclinical atherosclerosis.

Unmet Hearing Health Care Needs: The Beaver Dam Offspring 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.

The Prevalence of Hearing Impairment and Associated Risk Factors

To investigate long‐term variability in serum high‐sensitivity C‐reactive protein (CRP) and interleukin‐6 (IL‐6) and to determine associated risk factors for high‐risk inflammatory profiles.