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Ronald Klein

Publications and source records attributed to Ronald Klein.

At least 109 records · Page 6Linked to original sources
PubMed2004

Retinal arteriolar narrowing is associated with 5-year incident severe hypertension: the Blue Mountains Eye Study.

We assessed whether retinal arteriolar narrowing and structural abnormalities independently predicted 5-year incident severe (grade 2 or 3) hypertension in an older population-based cohort. The Blue Mountains Eye Study baseline (1992 to 1994) examined 3654 residents aged 49 and older in 2 postal code areas, west of Sydney. Of the 2335 participants (75.1% of survivors) who returned at the 5-year examinations, 1319 were normotensive or had mild (grade 1) hypertension at baseline. Baseline retinal photographs were graded for focal retinal vessel wall signs and vessel diameters were measured. Participants were classified as having normal, high-normal blood pressure [BP] (systolic BP 121 to 139 mm Hg and/or diastolic BP 81 to 89 mm Hg), mild hypertension (systolic BP 140 to 159 mm Hg and/or diastolic BP 90 to 99 mm Hg), or severe hypertension if they had a previous diagnosis of hypertension and were receiving antihypertensive medications or had systolic BP > or =160 mm Hg and/or diastolic BP > or =100 mm Hg at examination. Incident severe hypertension was defined in persons who were free of severe hypertension at baseline but classified as having severe hypertension at the 5-year examinations. Of the 1319 baseline subjects at risk, 390 (29.6%) developed severe hypertension. After adjusting for age, sex, body mass index, smoking, glucose, and total cholesterol, generalized retinal arteriolar narrowing at baseline was associated with increased risk of incident severe hypertension (odds ratio 2.6; 95% confidence interval, 1.7 to 3.9) when comparing the narrowest versus widest quintile. This association remained significant after further adjustment for baseline mean arterial BP or BP status. Our findings support the hypothesis that small vessel structural changes may precede the development of severe hypertension.

Aged↗
PubMed2004

Prospective cohort study of retinal vessel diameters and risk of hypertension.

OBJECTIVE: To examine the relation between diameters of the retinal arterioles and 10 year incidence of hypertension. DESIGN: Population based prospective cohort study. SETTING: Beaver Dam eye study. PARTICIPANTS: 2451 normotensive people aged 43 to 84 years. MAIN OUTCOME MEASURES: Diameters of retinal arterioles and venules measured from digitised photographs of the retina taken at baseline. Measurements summarised as the arteriole:venule ratio, with a lower ratio indicating smaller arteriolar diameters. Incident hypertension, defined as systolic blood pressure > or =140 mm Hg, diastolic blood pressure > or =90 mm Hg, or use of antihypertensive drugs during follow up. RESULTS: 721 participants developed hypertension over a 10 year period. Those with lower arteriole:venule ratio had a higher cumulative incidence of hypertension (incidences of 17.4%, 24.1%, 31.0%, and 45.1%, respectively, for decreasing quarters of distribution of arteriole:venule ratio). After adjustment for age and sex, participants with arteriole:venule ratios in the lowest quarter had a threefold higher risk of hypertension (odds ratio 2.95, 95% confidence interval 2.77 to 3.88) than those with ratios in the highest quarter. This association remained significant after further adjustment for baseline systolic and diastolic blood pressure and other risk factors (1.82, 1.39 to 2.40, for lowest versus highest ratio quarters). CONCLUSIONS: Narrowed retinal arterioles are associated with long term risk of hypertension, suggesting that structural alterations of the microvasculature may be linked to the development of hypertension.

Adult↗
PubMed2004

A prospective cohort study of retinal arteriolar narrowing and mortality.

The authors examined the relation of narrowed retinal arteriolar diameters, a marker of hypertensive damage, to mortality in a population-based cohort of 4,926 persons aged 43-84 years living in Wisconsin. A computer-assisted method was used to measure retinal vessel diameters from digitized retinal photographs taken at the baseline examination (1988-1990). These measurements were summarized as the retinal arteriole-to-venule ratio (AVR), with a smaller AVR indicating narrower arterioles compared with venules. Its relation to 10-year mortality was analyzed by using Cox proportional hazards models, adjusting for age, gender, blood pressure, diabetes, and other risk factors. No relation was found between smaller AVR and increased mortality. In relation to the largest AVR quartile, the adjusted relative risks of all-cause mortality were 0.93 for the smallest AVR quartile, 0.71 for the second AVR quartile, and 0.80 for the third AVR quartile. Results were largely similar in analyses of cause-specific mortality (vascular disease and non-vascular-disease mortality) and in subgroups stratified by age, gender, and diabetes and hypertension status. These data contrast with recent studies showing a relation between narrowed retinal arterioles and increased cardiovascular risk, suggesting that further research is needed to understand the systemic associations of retinal microvascular changes.

Adult↗
PubMed2004

Sleep-disordered breathing is not associated with the presence of retinal microvascular abnormalities: the Sleep Heart Health Study.

STUDY OBJECTIVE: Sleep apnea and milder forms of sleep-disordered breathing (SDB) have been associated with overt clinical cardiovascular disease, but it is unknown whether SDB is associated with arterial microvascular pathology. We examined the relation between SDB and retinal microvascular abnormalities. DESIGN: Cross-sectional study. PARTICIPANTS: Subjects were 2,927 men and women, aged 51 to 97 years, who participated in the Sleep Heart Health Study and had retinal photographs taken within approximately 3 years of overnight, unattended, at-home polysomnography. MEASUREMENTS AND RESULTS: A respiratory disturbance index (RDI), calculated as the average number of apneas and hypopneas per hour of sleep, was used as an indicator of SDB in analysis. The overall prevalence of retinopathy was slightly higher in people with higher RDI values (5.4%, 4.9%, 8.6%, and 7.6%, respectively, in increasing quartiles of RDI), but after adjustment for age, body-mass index, hypertension, diabetes, and other factors, the presence of retinopathy was not associated with SDB. With the possible exceptions of microaneurysms and generalized arteriolar narrowing, as measured by lower arteriole-to-venule ratio, specific retinal abnormalities were not associated consistently with the RDI. Relative to the first quartile of RDI, the adjusted odds ratios (95% confidence interval) for the presence of microaneurysm in the second, third, and fourth quartiles of RDI were 1.05 (0.44-2.55), 1.97 (0.89-4.37), and 1.79 (0.78-4.10), respectively. An increase of RDI from 0 to 10 was associated with a predicted decrease in arteriole-to-venule ratio of 0.01. Results were similar when analyses were conducted in normotensive and nondiabetic persons separately. CONCLUSIONS: These data do not demonstrate a notable relation between SDB and retinal abnormalities. However, since this is the first investigation of a link between retinopathy and SDB, similar studies should be conducted in other population samples to demonstrate either consistency or inconsistency of our findings across studies.

Aged↗
PubMed2004

Relationship between carotid artery stiffness and retinal arteriolar narrowing in healthy middle-aged persons.

BACKGROUND AND PURPOSE: Both carotid atherosclerosis and cerebral arteriolosclerosis are associated with stroke. However, the relationship between carotid atherosclerosis and cerebral arteriolosclerosis is unknown. We examined the association between carotid artery stiffness, a marker of early atherosclerosis, and retinal arteriolar narrowing, a marker of arteriolosclerosis, in healthy middle-aged people. METHODS: This population-based, cross-sectional study involved 8031 men and women 45 to 64 years of age. Carotid arterial stiffness was estimated from high-resolution ultrasonic echo tracking of the left common carotid artery and was defined as adjusted arterial diameter change (AADC, micro, adjusted for diastolic blood pressure, pulse pressure and pulse pressure squared, and diastolic arterial diameter and height, with smaller AADC reflecting greater arterial stiffness). Generalized retinal arteriolar narrowing was estimated from measurements of diameters of retinal vessels from digitized retinal photographs and summarized as the arteriole-to-venule ratio (AVR, with smaller AVR indicating greater retinal arteriolar narrowing). RESULTS: After controlling for age, sex, ethnicity, hypertension, diabetes, and cigarette smoking, decreasing AADC was associated with decreasing AVR. The mean AADCs, comparing the lowest and highest quartiles of AVR, were 394 (SE, 4) and 409 (SE, 4) micro, respectively (P<0.01). The pattern of the graded association between carotid arterial stiffness and generalized retinal arteriolar narrowing was similar among persons with and without hypertension. CONCLUSIONS: Greater stiffness of the carotid arteries is related to generalized narrowing of the retinal arterioles independent of blood pressure and other vascular factors. This supports a relationship between macrovascular and microvascular disease processes important in stroke pathogenesis.

Arterioles↗
PubMed2004

Retinal arteriolar diameter and risk for hypertension.

BACKGROUND: Narrowing of the small arterioles has been hypothesized to contribute to the pathogenesis of hypertension, but prospective clinical data are lacking. OBJECTIVE: To examine the relation of retinal arteriolar narrowing to incident hypertension in healthy middle-aged persons. DESIGN: Prospective cohort study. SETTING: The population-based Atherosclerosis Risk in Communities Study, conducted in 4 U.S. communities. PARTICIPANTS: 5628 persons 49 to 73 years of age without preexisting hypertension. MEASUREMENTS: Diameters of retinal vessels were measured from digitized retinal photographs. A summary arteriole-to-venule ratio was computed as an indicator of generalized arteriolar narrowing; a lower ratio indicated greater narrowing. Areas of focal arteriolar narrowing were defined from photographs by using a standard protocol. Incident hypertension, defined as systolic blood pressure of 140 mm Hg or higher, diastolic blood pressure of 90 mm Hg or higher, or use of antihypertensive medication, was identified from the cohort. RESULTS: After 3 years of follow-up, 811 (14.4%) persons had developed hypertension. The incidence of hypertension was higher in persons with lower arteriole-to-venule ratios (incidence of 8.9%, 12.3%, 13.7%, 14.3%, and 22.3%, comparing decreasing quintiles of the ratio) and in persons with focal arteriolar narrowing than in those without focal arteriolar narrowing (25.1% vs. 13.0%). After the authors controlled for the average systolic and diastolic blood pressures over the preceding 6 years, body mass index, waist-to-hip ratio, and other risk factors, the odds of developing hypertension were approximately 60% higher in persons with lower arteriole-to-venule ratios (odds ratio, 1.62 [95% CI, 1.21 to 2.18] comparing lowest to highest quintile; P = 0.006 for trend) and focal arteriolar narrowing (odds ratio, 1.61 [CI, 1.27 to 2.04]; P < 0.001). CONCLUSIONS: Smaller retinal arteriolar diameters are independently associated with incident hypertension, which suggests that arteriolar narrowing may be linked to the occurrence and development of hypertension.

Aged↗
PubMed2004

The relation of retinal vessel caliber to the incidence and progression of diabetic retinopathy: XIX: the Wisconsin Epidemiologic Study of Diabetic Retinopathy.

OBJECTIVE: To describe the relation of retinal arteriolar and venular caliber to the incidence and progression of diabetic retinopathy in people with type 1 diabetes mellitus. DESIGN: Incidence findings in a population-based study of diabetic retinopathy in Wisconsin. Participants included 996 persons diagnosed as having diabetes mellitus before 30 years of age who took insulin and underwent the baseline examination, 891 in the 4-year follow-up, 765 in the 10-year follow-up, and 634 in the 14-year follow-up. Retinal photographs of 7 standard fields were taken at all examinations. Computer-assisted grading was performed from a digitized image of field 1 to determine the average diameter of retinal arterioles and venules and their ratio. Main outcome measures included incidence and progression of retinopathy, incidence of proliferative retinopathy, and macular edema. RESULTS: While adjusting for other factors, larger arteriolar (relative risk [RR] for the fourth vs first quartile range, 2.04; 95% confidence interval [CI], 1.20-3.47; test of trend, P =.008) and venular diameters (RR, 2.33; 95% CI, 1.37-3.95; test of trend, P =.005) were associated with greater 4-year progression of retinopathy. Larger venular diameters (RR, 4.28; 95% CI, 1.50-12.19; test of trend, P =.006) but not arteriolar diameters were associated with greater 4-year incidence of proliferative retinopathy. In multivariable analyses, arteriolar and venular calibers were not associated with the 4-year incidence of retinopathy. While adjusting for other factors, arteriolar and venular calibers were not associated with incidence of macular edema at 4 years. There were few associations of arteriolar or venular caliber with the 10- or 14-year incidence or the progression of retinopathy. CONCLUSIONS: Larger arteriolar and venular caliber, independent of retinopathy severity level, is related to the progression of retinopathy, and larger venular caliber is associated with the 4-year incidence of proliferative retinopathy. Caliber of retinal vessels is not associated with incident retinopathy. These data suggest a quantitative measure of retinal vascular caliber provides additional information regarding risk for progression of retinopathy.

Adult↗
PubMed2004

Detection of age-related macular degeneration using a nonmydriatic digital camera and a standard film fundus camera.

OBJECTIVE: To compare gradings of lesions associated with age-related macular degeneration (AMD) from digital and stereoscopic film images. DESIGN: Instrument validation study. PARTICIPANTS: Sixty-two subjects (124 eyes) with varying degrees of AMD, including no AMD. METHODS: Images of the optic disc and macula were taken using a 45 degrees digital camera (6.3 megapixels) through dark-adapted pupils and pharmacologically dilated pupils. In addition, 30 degrees stereoscopic retinal film images were taken through pharmacologically dilated pupils of the same eyes. All images were graded for drusen size, type, and area; pigmentary abnormalities; geographic atrophy; and neovascular lesions using the modified Wisconsin Age-Related Maculopathy Grading System. Exact agreement and unweighted kappa scores were calculated for paired gradings resulting from digital and film images. MAIN OUTCOME MEASURE: Agreement between gradings obtained from stereoscopic slide transparencies and digital nonstereoscopic images. RESULTS: Exact agreement between gradings of digital and stereoscopic film images taken through pharmacologically dilated pupils was 91% (kappa = 0.85) for the categories of none, early AMD, and late AMD. Exact agreement for gradings of digital images taken through dark-adapted pupils compared with gradings of film images was 80% (kappa = 0.69). Exact agreement for gradings of digital images captured through dark-adapted and pharmacologically dilated pupils was 86% (kappa = 0.78). In addition, kappa scores for agreement between different approaches for individual lesions were moderate to almost perfect. CONCLUSIONS: Gradings resulting from high-resolution digital images, especially when the pupil is pharmacologically dilated, are comparable with those resulting from film-based images. We conclude that digital imaging of the retina is useful for epidemiological studies of AMD.

Adult↗
PubMed2004

Incidence of dry eye in an older population.

OBJECTIVES: To estimate the 5-year incidence of dry eye and to examine its association with risk factors. METHODS: The population of Beaver Dam, Wis, that was 43 to 84 years of age (n = 5924) was examined in the 1988-1990 (n = 4926), 1993-1995 (n = 3722), and 1998-2000 study phases (n = 2962). At the 1993-1995 examination, when dry eye data were first collected, and the 1998-2000 examination, 2783 subjects participated, and 44 were interviewed. Of these, 2802 provided dry eye history. The incidence cohort consisted of 2414 subjects not reporting dry eye in the 1993-1995 examination. Risk factor information was ascertained at the 1993-1995 examination and included demographics, medical history, cardiovascular disease risk factors, medications, and lifestyle factors. RESULTS: During the 5-year interval between examinations, a history of dry eye developed in 322 of 2414 subjects, for an incidence of 13.3% (95% confidence interval [CI], 12.0%-14.7%). Incidence was significantly associated with age (P<.001). After adjusting for age, incidence was greater in subjects with a history of allergy or diabetes, who used antihistamines or diuretics, and with poorer self-rated health (P<.05). Age-adjusted incidence was less in subjects using angiotensin-converting enzyme inhibitors or consuming alcohol (P<.05). It was not significantly associated with sex, blood pressure, hypertension, serum total or high-density lipoprotein cholesterol level, body mass index, history of arthritis, gout, osteoporosis, cardiovascular disease, thyroid disease, or smoking, and use of caffeine, vitamins, antianxiety medications, antidepressants, calcium channel blockers, or anticholesterolemics. CONCLUSIONS: Incidence of dry eye is substantial. However, there are few associated risk factors. Some drugs (eg, diuretics and antihistamines) are associated with a greater risk, whereas others (angiotensin-converting enzyme inhibitors) are associated with lower risk.

Adult↗
PubMed2004

Causes and prevalence of visual impairment among adults in the United States.

OBJECTIVES: To estimate the cause-specific prevalence and distribution of blindness and low vision in the United States by age, race/ethnicity, and gender, and to estimate the change in these prevalence figures over the next 20 years. METHODS: Summary prevalence estimates of blindness (both according to the US definition of < or =6/60 [< or =20/200] best-corrected visual acuity in the better-seeing eye and the World Health Organization standard of < 6/120 [< 20/400]) and low vision (< 6/12 [< 20/40] best-corrected vision in the better-seeing eye) were prepared separately for black, Hispanic, and white persons in 5-year age intervals starting at 40 years. The estimated prevalences were based on recent population-based studies in the United States, Australia, and Europe. These estimates were applied to 2000 US Census data, and to projected US population figures for 2020, to estimate the number of Americans with visual impairment. Cause-specific prevalences of blindness and low vision were also estimated for the different racial/ethnic groups. RESULTS: Based on demographics from the 2000 US Census, an estimated 937 000 (0.78%) Americans older than 40 years were blind (US definition). An additional 2.4 million Americans (1.98%) had low vision. The leading cause of blindness among white persons was age-related macular degeneration (54.4% of the cases), while among black persons, cataract and glaucoma accounted for more than 60% of blindness. Cataract was the leading cause of low vision, responsible for approximately 50% of bilateral vision worse than 6/12 (20/40) among white, black, and Hispanic persons. The number of blind persons in the US is projected to increase by 70% to 1.6 million by 2020, with a similar rise projected for low vision. CONCLUSIONS: Blindness or low vision affects approximately 1 in 28 Americans older than 40 years. The specific causes of visual impairment, and especially blindness, vary greatly by race/ethnicity. The prevalence of visual disabilities will increase markedly during the next 20 years, owing largely to the aging of the US population.

Adult↗
PubMed2004

The prevalence of diabetic retinopathy among adult type 1 diabetic persons in the United States.

OBJECTIVE: To estimate the US prevalence of diabetic retinopathy (DR) among persons with type 1 diabetes mellitus (DM). METHODS: Prevalence data from the New Jersey 725 and Wisconsin Epidemiologic Study of Diabetic Retinopathy were used to estimate the prevalence of DR by age, gender, and race among persons 18 years and older having type 1 DM diagnosed before age 30 years. Severity of DR was determined via masked grading of 7-field stereoscopic fundus photographs. Any DR was defined as retinopathy severity level of 14 or more; and vision-threatening retinopathy, as retinopathy severity level of 50 or more, the presence of clinically significant macular edema, or both. The estimates of the prevalence of DR among persons with type 1 DM were applied to the estimated number of persons with type 1 DM diagnosed before age 30 years in the 2000 US population to obtain prevalence estimates of DR due to type 1 DM in the general population. RESULTS: Among 209 million Americans 18 years and older, an estimated 889 000 have type 1 DM diagnosed before age 30 years. Among persons with type 1 DM, the crude prevalences of DR of any level (74.9% vs 82.3% in black and white persons, respectively) and of vision-threatening retinopathy (30.0% vs 32.2%, respectively) are high. The prevalence of DR due to type 1 DM diagnosed before age 30 years in the general population 18 years and older is estimated at 767 000 persons having DR of any level (0.37%), and 376 000 persons having vision-threatening retinopathy (0.18%). CONCLUSION: Retinopathy due to type 1 DM is an important public health problem in the United States, affecting 1 per 300 persons 18 years and older, and 1 per 600 persons with advanced, vision-threatening retinopathy.

Adolescent↗
PubMed2004

The prevalence of diabetic retinopathy among adults in the United States.

OBJECTIVE: To determine the prevalence of diabetic retinopathy among adults 40 years and older in the United States. METHODS: Pooled analysis of data from 8 population-based eye surveys was used to estimate the prevalence, among persons with diabetes mellitus (DM), of retinopathy and of vision-threatening retinopathy-defined as proliferative or severe nonproliferative retinopathy and/or macular edema. Within strata of age, race/ethnicity, and gender, US prevalence rates were estimated by multiplying these values by the prevalence of DM reported in the 1999 National Health Interview Survey and the 2000 US Census population. RESULTS: Among an estimated 10.2 million US adults 40 years and older known to have DM, the estimated crude prevalence rates for retinopathy and vision-threatening retinopathy were 40.3% and 8.2%, respectively. The estimated US general population prevalence rates for retinopathy and vision-threatening retinopathy were 3.4% (4.1 million persons) and 0.75% (899 000 persons). Future projections suggest that diabetic retinopathy will increase as a public health problem, both with aging of the US population and increasing age-specific prevalence of DM over time. CONCLUSION: Approximately 4.1 million US adults 40 years and older have diabetic retinopathy; 1 of every 12 persons with DM in this age group has advanced, vision-threatening retinopathy.

Adult↗
PubMed2004

Sunlight and the 10-year incidence of age-related maculopathy: the Beaver Dam Eye Study.

OBJECTIVE: To examine the association of sunlight exposure and indicators of sun sensitivity with the 10-year incidence of age-related maculopathy (ARM). DESIGN: Population-based cohort study. PARTICIPANTS: We included persons aged 43 to 86 years at the baseline examination from 1988 to 1990, living in Beaver Dam, Wis, of whom 3684 persons underwent 5-year follow-up and 2764 underwent 10-year follow-up. METHODS: Data on sun exposure and indicators of sun sensitivity were obtained from a standardized questionnaire administered at baseline and/or follow-up. We determined ARM status by grading stereoscopic color fundus photographs using the Wisconsin Age-Related Maculopathy Grading System. MAIN OUTCOME MEASURES: Incidence and progression of ARM. RESULTS: While controlling for age and sex, we found that participants exposed to the summer sun for more than 5 hours a day during their teens, in their 30s, and at the baseline examination were at a higher risk of developing increased retinal pigment (risk ratio [RR], 2.99; 95% confidence interval [CI], 1.18-7.60; P =.02) and early ARM (RR, 2.20; 95% CI, 1.02-4.73; P =.04) [corrected] by 10 years than those exposed less than 2 hours per day during the same periods. In participants reporting the highest summer sun exposure levels in their teens and 30s, the use of hats and sunglasses at least half the time during the same periods was associated with a decreased risk of developing soft indistinct drusen (RR, 0.55; 95% CI, 0.33-0.90; P =.02) and retinal pigment epithelial depigmentation (RR, 0.51; 95% CI, 0.29-0.91; P =.02). Participants who experienced more than 10 severe sunburns during their youth were more likely than those who experienced 1 or no burn to develop drusen with a 250-microm diameter or larger (RR, 2.52; 95% CI, 1.29-4.94 [corrected] P =.01) by the 10-year examination. No relationships were found between UV-B exposure, winter leisure time spent outdoors, skin sun sensitivity, or number of bad sunburns experienced by the time of the baseline examination and the 10-year incidence and progression of ARM or its associated lesions. CONCLUSIONS: Few significant relationships between environmental exposure to light and the 10-year incidence and progression of ARM were found in the Beaver Dam Eye Study. Consistent with results from the baseline and 5-year follow-up examinations, significant associations were found between extended exposure to the summer sun and the 10-year incidence of early ARM and increased retinal pigment. A protective effect of hat and sunglasses use by participants while in their teens and 30s against the 10-year incidence of soft indistinct drusen and retinal pigment epithelial depigmentation was also found, but only in those who reported the highest amount of sun exposure during the same periods.

Adult↗
PubMed2004

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.

Aged↗
PubMed2004

The relation of retinal microvascular characteristics to age-related eye disease: the Beaver Dam eye study.

PURPOSE: To examine the relationship between microvascular characteristics (central retinal artery equivalent [CRAE], central retinal vein equivalent [CRVE], arteriole-to-venule ratio [AVR], focal retinal arteriolar narrowing, arteriovenous [A/V] nicking, and retinopathy) associated with systemic hypertension and ocular disease (age-related maculopathy [ARM], three types of cataract, and open-angle glaucoma). DESIGN: Population-based cohort study. METHODS: Standardized grading of microvascular characteristics was performed at baseline on fundus photographs taken on 4,926 persons aged 43 to 86 years who participated in the Beaver Dam Eye study at the baseline examination. Age-related maculopathy, cataract, and glaucoma status were determined at baseline; ARM and cataract were again determined at 5-year and 10-year follow-up examinations using standard protocols. RESULTS: While controlling for age and sex, generalized retinal arteriolar narrowing (lowest quintile of CRAE) was associated with the 10-year cumulative incidence of retinal pigment epithelial (RPE) depigmentation (risk ratio [RR] 1st vs 5th quintile, 1.93; 95% confidence interval [CI], 1.11, 3.34) and, inversely, with incident nuclear cataract (RR, 0.71; 95% CI, 0.50, 0.99). Arteriovenous nicking was associated with the incidence of early ARM (RR, 2.39; 95% CI, 1.02, 5.57). Otherwise, there were no statistically significant associations of focal arteriolar narrowing or retinopathy with incident ARM or any type of age-related cataract and no relation of CRAE, focal arteriolar narrowing, A/V nicking, or retinopathy with the prevalence of glaucoma. CONCLUSION: These data show that retinal vascular characteristics associated with hypertension are related to the incidence of ARM and nuclear cataract but not to prevalent glaucoma. Relationships, however, were weak and inconsistent.

Adult↗
PubMed2004

Pathogenesis of lesions in late age-related macular disease.

PURPOSE: To review the evidence that exists concerning the pathogenesis of lesions in late age-related macular disease (AMD). DESIGN: Review of the literature. METHODS: A review of both experimental evidence and clinical observations that address these problems. RESULTS: There is good evidence that choroidal neovascularization (CNV) is due to a change in the balance of growth factors derived from the retinal pigment epithelial basolateral plasma membrane domain (retinal pigment epithelium). Retinal angiomatous proliferation may also have a similar pathogenesis involving the apical domain. Detachment of the retinal pigment epithelium is likely to be a consequence of increased resistance of the Bruch membrane to water flow due to deposition of lipids. Geographic atrophy is preceded by accumulation of autofluorescent material in the retinal pigment epithelium and possible causal relationships between the two have been demonstrated. CONCLUSION: There is increasing understanding concerning the sequence of events that lead to those lesions causing loss of central vision in AMD. Therapeutic approaches that address the underlying mechanisms are more likely to succeed than current treatment options. Such an approach has already been initiated in the management of choroidal neovascularization.

Humans↗