Prevalence of age-related maculopathy. The Beaver Dam Eye Study.

PURPOSE: The relationships of retinal drusen, retinal pigmentary abnormalities, and macular degeneration to age and sex were studied in 4926 people between the ages of 43 and 86 years who participated in the Beaver Dam Eye Study. METHODS: The presence and severity of various characteristics of drusen and other lesions typical of age-related maculopathy were determined by grading stereoscopic color fundus photographs using the Wisconsin Age-Related Maculopathy Grading System. RESULTS: One or more drusen were present in the macular area of at least 1 eye in 95.5% of the population. People 75 years of age or older had significantly higher frequencies (P less than 0.01) of the following characteristics than people 43 to 54 years of age: larger sized drusen (greater than or equal to 125 microns, 24.0% versus 1.9%), soft indistinct drusen (23.0% versus 2.1%), retinal pigment abnormalities (26.6% versus 7.3%), exudative macular degeneration (5.2% versus 0.1%), and geographic atrophy (2.0% versus 0%). CONCLUSION: These data indicate signs of age-related maculopathy are common in people 75 years of age or older and may pose a substantial public health problem.     

Prevalence of age-related lens opacities in a population. The Beaver Dam Eye Study.

Age-related lens opacities are common and are a frequent cause of loss of vision. The Beaver Dam Eye Study was designed to estimate the prevalence and severity of lens opacities in a rural community in the United States. Adults between the ages of 43 and 84 years, identified by private census, were examined and participated in the study (n = 4926). Photographs were taken of the lenses and were graded in masked fashion according to a standardized protocol. For nuclear sclerosis, more severe levels occurred more commonly in older age groups and in women. Overall, 17.3% had nuclear sclerosis more severe than level 3 in a 5-step scale of severity. Cortical opacities increased with increasing age and were more common in women. They were found in 16.3% of the population. Posterior subcapsular opacities occur in 6.0% of the population. There was a significant trend of greater prevalence at older ages, but no sex effect. The frequency of early cataract increased in both sexes through the age group 65 to 74 years, but declined in those 75 years of age and older. The frequency of late cataract increased consistently with age. Women were more severely affected than men. This study confirms that lens opacities are common in adults in the United States. These data are important for providing for social and health care needs. It is important to determine causes of cataracts in order to develop preventive programs.     

The Beaver Dam Eye Study: visual acuity

Few current population-based data on visual impairment are available. Visual acuity and impairment were measured in 4926 people between the ages of 43 and 86 years in the defined population participating in the Beaver Dam Eye Study. Visual acuity was measured after refraction, using standardized protocols. Of a possible maximum score of 70 (20/10), the mean number of letters correctly identified (right eye) varied from 55.7 (20/20, n = 1515) in people between the ages of 43 and 54 years to 41.2 (20/40, n = 795) in people 75 years of age or older. Age-specific mean visual acuity scores were consistently and significantly lower in women, who identified three fewer letters on the average than men. Rates of any visual impairment (20/40 or worse in the better eye) or legal blindness (20/200 or worse in the better eye), increased from 0.8% and 0.1%, respectively, in people between the ages of 43 and 54 years to 21.1% and 2.0%, respectively, in people 75 years of age or older. Multivariate analyses showed both sex (women) and age (older) to be significant and independent predictors of poorer visual acuity.     

Heritability of risk factors for primary open-angle glaucoma: the Beaver Dam Eye Study

PURPOSE: To investigate the family aggregation and heritability of risk indicators of primary open-angle glaucoma. METHODS: During the baseline examination of the Beaver Dam Eye Study, standardized measurements of intraocular pressure were performed with a Goldmann applanation tonometer. Stereoscopic photographs of the optic discs were taken of both eyes of each study participant. The eyes were graded for the size of the optic disc and cup according to a standardized protocol, with graders masked to other subject characteristics. Family members who had participated in the examination phase were identified. RESULTS: Correlations in sibling pairs (n = 1136), parent-child pairs (n = 514), and cousin pairs (n = 1807) for intraocular pressure were 0.17, 0.18, and 0.12, respectively and were all statistically significant, whereas the spouse pair correlation was not. Correlations for sibling, parent-child, and avuncular pairs were higher for vertical optic disc, vertical optic cup, and vertical cup-to-disc ratio than for intraocular pressure. Heritability estimates were 0.36, 0.55, 0.57, and 0.48 for intraocular pressure, optic cup diameter, optic disc diameter, and cup-to-disc ratio, respectively. Correlations for the optic disc parameters were compatible with the amount of gene sharing in relative pairs of different degrees. CONCLUSIONS: Risk indicators of open-angle glaucoma correlate highly in families, and the patterns are consistent with the hypothesis of genetic determinants of these factors.     

Intraocular pressure in an American community. The Beaver Dam Eye Study.

The Beaver Dam Eye Study is a population-based study of age-related eye diseases in persons 43-86 yr of age. Applanation tonometry was done on all study subjects. Mean intraocular pressure (IOP) increased significantly with age. Mean IOP differed little between the sexes and was not significantly different after age adjustment (in right eyes of 2721 women, it was 15.5 mm Hg, and in right eyes of 2135 men, it was 15.3 mm Hg). There was an association of IOP with systolic and diastolic blood pressures, body mass index, hematocrit, serum glucose, glycohemoglobin, cholesterol level, pulse, nuclear sclerosis, season, and time of day of measurement. These data confirm that, in a general population, IOP is associated with important systemic and ocular characteristics. Those characteristics should be considered in further research on determinants of IOP.     

Diabetes, hyperglycemia, and age-related maculopathy. The Beaver Dam Eye Study.

PURPOSE: The purpose of this study is to examine the association among hyperglycemia, diabetes status, and age-related maculopathy in a population-based study of people between the ages of 43 and 86 years who lived in Beaver Dam, Wisconsin between 1988 and 1990. METHODS: Age-related maculopathy was determined from stereoscopic fundus photographs. RESULTS: In the nondiabetic group (n = 4291), no relationship was found between glycosylated hemoglobin and any signs of age-related maculopathy. Diabetes status was not associated with early age-related maculopathy. People 75 years of age or older with diabetes (n = 85) had a higher frequency of exudative macular degeneration (9.4%) than those without (4.7%) but had similar frequencies of pure geographic atrophy (3.8% for those with diabetes and 3.4% for those without diabetes). The relative risk of exudative macular degeneration in men with diabetes who were 75 years of age or older compared with those who did not have diabetes was 10.2 (95% confidence interval [CI]: 2.4, 43.7); for females it was 1.1 (95% CI: 0.4, 3.0). CONCLUSION: These data suggest that diabetes is not related to early age-related maculopathy or geographic atrophy. The relationship of exudative macular degeneration to diabetes in older men, but not women, may be a result of chance. Further longitudinal study of this observation is needed.     

The prevalence and 5-year incidence of ocular trauma. The Beaver Dam Eye Study

PURPOSE: To describe the cumulative lifetime prevalence and 5-year incidence of ocular trauma and their relation to risk factors in a defined white adult population living in a small town. DESIGN: Population-based cross-sectional and follow-up study. PARTICIPANTS: Participants aged 43 to 86 years from the baseline Beaver Dam Eye Study that took place from 1988 through 1990 (n = 4926) and the follow-up study that took place from 1993 through 1995 (n = 3684). METHODS: Standardized interview at baseline and follow-up study. MAIN OUTCOME MEASURES: Cumulative lifetime prevalence and 5-year incidence of self-reported history of ocular trauma. RESULTS: The cumulative lifetime prevalence and 5-year incidence of ocular trauma was 19.8% (n = 972) and 1.6% (n = 57), respectively. A history of trauma in both eyes was reported in 15% of the prevalent cases and 8% of the incident cases. Sharp objects caused more than half of all injuries. Persons aged 43 through 54 years were 2.5 times more likely to have a lifetime history of ocular trauma than persons aged 75 and older (odds ratios [OR], 2.57; 95% confidence interval [CI], 2.0, 3.29). Males had four times the prevalence of females (OR, 4. 42; 95% CI, 3.79, 5.16). Almost one third of all males aged 43 through 54 years reported a history of ocular trauma in their lifetime. The higher risks in the 43 through 54 age group (OR, 1.60) and male gender (OR, 1.42) were not significant among incident cases. In multivariate analysis, blue collar (adjusted OR, 1.58; 95% CI, 1. 32, 1.89) and farm-related workers (adjusted OR, 1.32; 95% CI, 0.93, 1.87) had higher lifetime risks of ocular trauma compared with white collar workers. People with a history of fractures also had increased lifetime risks (adjusted OR, 1.30; 95% CI, 1.13, 1.52). A history of ocular trauma reported in the baseline examination was significantly associated with a higher risk of ocular trauma occurring again in the next 5 years (adjusted OR, 3.27; 95% CI, 1.76, 5.82), especially if both eyes had previous trauma (adjusted OR, 5.15; 95% CI, 2.03, 13.0). CONCLUSIONS: One fifth of white adult Americans more than 42 years of age residing in a small town reported ocular trauma in their lifetime. This group had a three times higher risk of experiencing ocular trauma again within 5 years.     

Assessment of cataracts from photographs in the Beaver Dam Eye Study

Presence and severity of age-related cataract was determined in adults 43 to 84 years of age in Beaver Dam, Wisconsin. Duplicate photograph gradings for nuclear sclerosis (n = 1160), cortical opacities (n = 1159), and posterior subcapsular cataract (n = 1137) were performed. There are five levels of nuclear sclerosis. Exact agreement occurred in 64.7% of the cases; agreement within one category in 99.8%. For cortical opacities, graders estimate involved area in nine segments of the lens. When the continuous scale is divided into 12 categories of severity, exact agreement varied between 73.5 and 82.4%; for agreement within one category, rates varied between 84.6 and 89.9%. For posterior subcapsular cataracts, exact agreement for involvement of the central circle occurred in 95.0% and agreement within one category occurred in 97.7%. Intraobserver comparisons disclosed similar concordance. These grading schemes are semiquantitative, reproducible, and can be performed for the large numbers of photographs from population-based studies.     

Frailty and age-related macular degeneration: the Beaver Dam Eye Study

PURPOSE: To investigate the associations of measures of frailty to prevalent age-related maculopathy (ARM). DESIGN: Cross-sectional population-based study. METHODS: Time to walk a measured course (gait-time), handgrip strength, peak expiratory flow rate, ability to stand from a sitting position without using arms, self-reported co-morbidities, and ARM were assessed at the third examination of the Beaver Dam Eye Study (n = 2,962). ARM was determined by grading stereoscopic color fundus photographs. RESULTS: While controlling for age, smoking, and the number of co-morbid conditions, weaker handgrip strength was associated with early ARM (odds ratio [OR]/10 kg decrease 1.28, confidence interval [CI] 1.08, 1.52, P = .004) and late ARM (OR 1.55, 95% CI 1.02, 2.36) in men but not women. Other measures of frailty were not related to ARM. CONCLUSIONS: A weak cross-sectional association of handgrip strength with ARM (in men) was found after controlling for co-morbid conditions. These data suggest that ARM is due to a specific disease process, albeit age-related, rather than to biologic aging, as reflected by measures of frailty.     

Refractive errors and incident cataracts: the Beaver Dam Eye Study

PURPOSE: To describe the relation between refractive errors and incident age-related cataracts in a predominantly white US population. METHODS: All persons aged 43 to 84 years of age in Beaver Dam, Wisconsin, were invited for a baseline examination from 1988 through 1990 and a follow-up examination 5 years later from 1993 through 1995. At both examinations, participants had refraction and photographic assessment of cataract, according to a standardized protocol. Myopia was defined as a spherical equivalent of -1.0 diopters (D) or less, hyperopia as +1.0 D or more. The relations between refractive errors at baseline and cataract at baseline (prevalent cataract), 5-year incident cataract, and incident cataract surgery were analyzed by using generalized estimating equations. RESULTS: When age and gender were controlled for, myopia was related to prevalent nuclear cataract (odds ratio [OR], 1.67; 95% confidence interval [CI], 1.23-2.27), but not to cortical and posterior subcapsular cataracts. Myopia was not related to 5-year incident nuclear, cortical, and posterior subcapsular cataracts, but was related to incident cataract surgery (OR 1.89; CI 1.18-3.04). Hyperopia was related to incident nuclear (OR 1.56; CI 1.25-1.95) and possibly cortical (OR 1.25; CI 0.96-1.63) cataracts, but not to posterior subcapsular cataract or cataract surgery. After further adjustment for diabetes, smoking, and education, the association between myopia and incident cataract surgery was attenuated (OR 1.60; CI 0.96-2.64), but the associations between hyperopia and incident nuclear and cortical cataracts were unchanged. CONCLUSIONS: These data support the cross-sectional association between myopia and nuclear cataract seen in other population-based studies, but provide no evidence of a relationship between myopia and 5-year incident cataract. Hyperopia may be related weakly to incident nuclear and cortical cataract.     

Lens thickness and five-year cumulative incidence of cataracts: The Beaver Dam Eye Study

PURPOSE: To evaluate whether lens thickness is related to incidence of cataracts. METHODS: Lens thickness was measured from slit-lamp photographs of the lens at the time of the prevalence evaluation in the Beaver Dam Eye Study. Incident cataract was determined by grading standard slit-lamp and retroillumination photographs of the lens at the baseline and five-year follow-up examinations. Medical history was obtained and blood pressures, height and weight were measured according to protocol. RESULTS: Lens thickness was positively associated with incident nuclear cataract and inversely associated with incident cortical cataract after accounting for age, sex, diabetes status, hypertension, heavy drinking and cigarette smoking. CONCLUSIONS: Lens thickness is related to incidence of cataracts. Mechanisms to explain these relationships require further laboratory and epidemiologic investigation.     

Drug use and five-year incidence of age-related cataracts: The Beaver Dam Eye Study

OBJECTIVE: To evaluate incident cataract after a 5-year interval with respect to medication use. DESIGN: Population-based incidence study. MAIN OUTCOME: Incident cataract judged from standard photographs. SETTING: Study subjects were adults 43 to 86 years of age in 1988 to 1990 and again in 1993 to 1995. All participants were examined and interviewed, and photographs were taken. All procedures and grading were done by protocols at both examinations. All medications in current use, prescribed as well as over-the-counter, were brought to the examination site, and the names were recorded at that time. RESULTS: There were 678 drug preparations (active ingredients) being used at the baseline examination. Significantly lower incidences of nuclear cataracts 5 years later occurred in those who took thiazide diuretics (odds ratio [OR] = 0.79, 95% confidence interval [CI] 0.63, 1.00) and aspirin (OR = 0.76, 95% CI 0.61, 0.95) at the baseline examination. There were significantly more incident cortical cataracts in those taking oral steroids (OR = 2.59, 95% CI 1.45, 4.62), amitriptyline (OR = 2.03, 95% CI 1.09, 3.79), oral hypoglycemic agents (OR 2.06, 95% CI 1.23, 3.44), and insulin (OR = 3.38, 95% CI 1.61, 7.08). There were significantly more incident posterior subcapsular cataracts in those taking potassium-sparing diuretics (OR = 2.13, 95% CI 1.42, 3.18) and oral hypoglycemic agents (OR = 2.89, 95% CI 1.57, 5.33). Considering past use with never and current use did not alter the patterns of associations. We were not able to separate the effects of antihypertensive or diuretic agents from that of hypertension. However, hypoglycemic agents were no longer associated with any cataract type after stratifying by diabetes status. CONCLUSIONS: Although many different medications were being used at the baseline examination in the Beaver Dam Eye Study cohort, few were associated with incident cataract. However, with the high frequency of use of medications and the possibility that effects of current exposure may occur in the future, it is reasonable to follow this and other older cohorts for the development of cataract.