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Objectives: To characterize intraocular pressure (IOP) changes during 6 years of follow-up among patients with early, newly diagnosed glaucoma randomized to no initial treatment in the Early Manifest Glaucoma Trial (control group) and to evaluate factors associated with IOP changes in this group., Methods: Early Manifest Glaucoma Trial control patients, aged 50 to 80 years at baseline, were followed up for 6 years or to the time of progression, when treatment could be initiated. After baseline, patients were followed up every 3 months with comprehensive ophthalmologic examinations, including Goldmann applanation tonometry. Change in IOP over 6 years was assessed by linear regression analyses., Results: At baseline, the median IOP of this cohort (N = 118) was 20.8 mm Hg and was higher for the 15 patients with exfoliation glaucoma (24.0 mm Hg vs 20.0 mm Hg for others; P = .005). In patients without exfoliation glaucoma, IOP remained stable during follow-up (median IOP change of -0.01 mm Hg/y; interquartile range, 0.85 mm Hg/y). In comparison, patients with exfoliation glaucoma showed a significantly larger median change of 0.96 mm Hg/y (interquartile range, 3.11 mm Hg/y) (P = .004). In the overall cohort, the only factor related to IOP change was exfoliation glaucoma (P < .001). Among patients without exfoliation glaucoma, no factors were associated with IOP change., Conclusions: In patients with early glaucoma, IOP remained stable without treatment during a 6-year period, regardless of baseline IOP, except for patients with exfoliation glaucoma, where IOP increased by almost 1 mm Hg annually. No factors, aside from exfoliation glaucoma, were related to longitudinal changes in IOP. These new natural history data may be useful in guiding management decisions for glaucoma treatment, particularly in patients with early disease or with exfoliation glaucoma.

Objective: To evaluate the relationship between open-angle glaucoma (OAG) and mortality in a black population at 9-years' follow-up., Design: Population-based cohort study of 4092 black participants (aged 40-84 years at baseline) in the Barbados Eye Studies. Open-angle glaucoma was defined by visual field defects and optic disc damage, based on standardized examinations and photograph gradings. Ocular hypertension was defined by an intraocular pressure greater than 21 mm Hg or treatment, without OAG damage. Mortality was ascertained from death certificates. Cox proportional hazards regression analyses determined associations with mortality., Results: After 9 years, 764 (19%) participants were deceased. Mortality was unrelated to overall OAG at baseline (n = 300) after adjustment for confounders. However, cardiovascular mortality tended to increase in persons with previously diagnosed/treated OAG (n = 141; relative risk [RR], 1.38, P = .07) and was significantly higher with treatment involving timolol maleate (RR, 1.91, P = .04). Cardiovascular deaths also tended to increase in persons with ocular hypertension at baseline (n = 498; RR, 1.28, P = .06)., Conclusions: In this black population, cardiovascular mortality tended to increase in persons with previously diagnosed/treated OAG and ocular hypertension. The excess mortality associated with timolol maleate treatment of OAG, also found in a white population, warrants further investigation.

Objective: To describe temporal changes in intraocular pressure (IOP) and associated risk factors after 9 years of follow-up in a population of African descent., Methods: Changes in IOP were evaluated in 2298 participants without glaucoma or IOP-lowering treatment at baseline. Risk factor analyses used a multiple regression approach with mixed effects, which accounted for intereye correlation., Results: The mean 9-year change in IOP was small, with relatively large dispersion (mean +/- SD, 0.4 +/- 4.0 mm Hg). Only 6.5% of persons with IOP of 21 mm Hg or less at baseline had elevated IOP greater than 21 mm Hg after 9 years. Mean IOP increases were largest in persons aged 50 to 59 years at baseline (mean +/- SD, 0.9 +/- 4.3 mm Hg), whereas IOP decreased in persons 70 years or older (mean +/- SD, -0.6 +/- 4.2 mm Hg). In multivariate analyses, IOP changes were positively associated with male sex, hypertension, diabetes history, and higher systolic and diastolic blood pressure at baseline, as well as with increases in blood pressure throughout 9 years (P<.05)., Conclusions: After long-term follow-up, minimal changes in IOP were observed in this African-origin population. The consistent relationships of hypertension and diabetes to IOP, a major glaucoma risk factor, underscore the public health importance of controlling these systemic conditions in black populations, where glaucoma incidence is high.

Objective: To estimate the 9-year incidence of diabetic retinopathy (DR) in a population with the same ancestry as African Americans., Methods: Participants with diabetes mellitus and gradable photographs at the 9-year examination were evaluated (n = 436). The incidences of minimum/moderate/severe DR, clinically significant macular edema (CSME), and sight-threatening DR (severe DR plus CSME) were defined by the development of specific diabetic changes in persons without those conditions at baseline. Progression was defined as the development of severe/proliferative DR in persons with minimum/moderate DR at baseline., Results: The 9-year DR incidence was 39.6% (38.0% for minimum, 9.0% for moderate, and 2.6% for severe/proliferative DR). Incidence tended to increase with diabetes duration and treatment. Of persons with preexisting DR at baseline, 8.2% progressed to proliferative DR. The CSME incidence was 8.7%, and it increased with diabetes duration, accounting for most of the overall incidence of sight-threatening DR., Conclusions: The study provides new data on long-term incidence among persons of African origin. Results suggest a possible lower risk of severe/proliferative DR than in whites, while CSME incidence seems comparable or higher. The main component of sight-threatening DR was CSME, highlighting the importance of DR as a cause of vision loss in this population.

Objective: To evaluate risk factors for the 4-year incidence of cortical and posterior subcapsular (PSC) lens opacities., Design: Population-based cohort study with 85% participation at 4-year follow-up., Participants: Three thousand one hundred ninety-three black participants of the Barbados Eye Studies, Barbados, West Indies, of whom 2040 and 2954 were free of cortical and PSC lens opacities, respectively, at baseline., Methods: The standardized protocol at baseline and follow-up included an interview, anthropometric and blood pressure measurements, and ophthalmic measurements including slitlamp lens grading, fundus photography, and an ophthalmologic examination. Factors associated with incident cortical and PSC opacities (Lens Opacities Classification System II, > or =2) were evaluated by logistic regression. Main Outcome Measure Relative risks (RRs) with 95% confidence intervals., Results: The 4-year incidence of cortical lens opacities was 22.2% (452/2040); the factors increasing risk were older age, female gender (RR = 1.3), low socioeconomic status (RR = 1.4), and a history of diabetes mellitus (RR = 2.4), while aspirin use was associated with a lower RR (RR = 0.2; 95% confidence interval, 0.1-0.8), a result based on small numbers. The 4-year incidence of PSC opacities was lower at 3.3% (97/2954), and risk also increased with age and a history of diabetes mellitus (RR = 2.9). A dose-response relationship was evident between incident opacities and increased levels of glycosylated hemoglobin at baseline, with the highest risk of cortical (RR = 3.60; 95% confidence interval, 2.23-5.81) and PSC (RR = 4.93; 95% confidence interval, 2.69-9.05) opacities at more than an 11.5% glycosylated hemoglobin level., Conclusions: Diabetes mellitus and hyperglycemia are major modifiable risk factors for the development of cortical and PSC lens opacities in this African-descent population with a high rate of diabetes mellitus. Prevention and improved control of diabetes mellitus are likely to reduce the burden of cataract. The finding of a reduced incidence of cortical lens opacities in aspirin users merits further investigation, given its potential for cataract prevention.

Objective: To estimate the prevalence and distribution of open-angle glaucoma (OAG) in the United States by age, race/ethnicity, and gender., Methods: Summary prevalence estimates of OAG were prepared separately for black, Hispanic, and white subjects in 5-year age intervals starting at 40 years. The estimated rates were based on a meta-analysis of recent population-based studies in the United States, Australia, and Europe. These rates were applied to 2000 US census data and to projected US population figures for 2020 to estimate the number of the US population with OAG., Results: The overall prevalence of OAG in the US population 40 years and older is estimated to be 1.86% (95% confidence interval, 1.75%-1.96%), with 1.57 million white and 398 000 black persons affected. After applying race-, age-, and gender-specific rates to the US population as determined in the 2000 US census, we estimated that OAG affects 2.22 million US citizens. Owing to the rapidly aging population, the number with OAG will increase by 50% to 3.36 million in 2020. Black subjects had almost 3 times the age-adjusted prevalence of glaucoma than white subjects., Conclusions: Open-angle glaucoma affects more than 2 million individuals in the United States. Owing to the rapid aging of the US population, this number will increase to more than 3 million by 2020.

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.

Objective: To evaluate the 4-year risk of high intraocular pressure (IOP) and associated factors in a black population without glaucoma at baseline., Design: Population-based incidence study., Participants: Random sample of Barbados residents aged 40 to 84 years. After 4 years, 3427 (85%) were reexamined., Main Outcome Measures: Development of elevated IOP (using percentile-based definitions) among individuals with an IOP of 21 mm Hg or lower and no glaucoma at baseline. Associations were evaluated using polychotomous logistic regression., Results: At baseline, 2856 participants did not have glaucoma or suspected glaucoma: 361 had an IOP higher than 21 mm Hg or received treatment, and 2495 had an IOP of 21 mm Hg or lower and no treatment. At follow-up, only 58% of the 361 participants remained free of glaucoma and had an IOP higher than 21 mm Hg, whereas 30% had an IOP of 21 mm Hg or lower. Among the remaining 2495 participants, the incidence of IOP higher than 21 mm Hg or treatment (80th percentile) was 12.9% (95% confidence interval, 11.7%-14.3%). Using other definitions of elevated IOP, estimates ranged from 1.5% to 11%. Incidence increased with age, with rates 2.5 times higher at 70 years or older than at ages 40 to 49 years. Factors associated with high IOP included age, baseline IOP, hypertension, and blood pressure. Whereas participants with an IOP between 21 mm Hg and 28 mm Hg had higher blood pressure readings, those with an IOP of 21 mm Hg or lower or an IOP higher than 28 mm Hg had similar values., Conclusions: Definitions of high IOP based on percentiles may be more applicable than those based on arbitrary values. Older individuals with a higher baseline IOP were more likely to develop elevated IOP after 4 years. Although blood pressure was also associated with high IOP, the relationship may be nonlinear.

Objectives: To describe the distribution of central corneal thickness (CCT) and evaluate its relationship to intraocular pressure (IOP) in the predominantly black population of the Barbados Eye Studies (BES)., Methods: Participants received a standardized examination, including pachymetry, applanation tonometry, and a comprehensive ophthalmologic evaluation. Analyses were based on data from all eyes, and generalized estimating equation methods were applied to account for the correlation between eyes., Results: Among the 1142 consecutive participants with pachymetry measurements, the mean age was 64.3 years, and 58% were women. Black participants tended to have thinner corneas (mean thickness, 529.8 microm) than mixed (black and white) (537.8 microm) and white participants (545.2 microm), respectively. Among black participants, increasing values of CCT were significantly related to younger age (P<.001), diabetes history (P =.03), and refractive error (P =.03); a marginally significant relationship (with thinner corneas) was found with a clinical diagnosis of glaucoma (P =.07). Intraocular pressure was not associated with CCT in this population., Conclusions: Although other studies have reported a positive correlation between CCT and IOP, such a relationship was not substantiated in the black BES population. Black participants tended to have thinner corneas than white participants, whereas younger individuals, as well as those with a history of diabetes and more positive refractive errors, had thicker corneas.

Objective: To assess factors for progression in the Early Manifest Glaucoma Trial (EMGT), including the effect of EMGT treatment., Setting/participants: Two hundred fifty-five open-angle glaucoma patients randomized to argon laser trabeculoplasty plus topical betaxolol or no immediate treatment (129 treated; 126 controls) and followed up every 3 months., Methods: Progression was determined by perimetric and photographic optic disc criteria. Patient-based risk of progression was evaluated using Cox proportional hazard regression models and was expressed as hazard ratios (HR) with 95% confidence intervals (95% CI)., Results: After 6 years, 53% of patients progressed. In multivariate analyses, progression risk was halved by treatment (HR = 0.50; 95% CI, 0.35-0.71). Predictive baseline factors were higher intraocular pressure (IOP) (ie, the higher the baseline IOP, the higher the risk), exfoliation, and having both eyes eligible (each of the latter 2 factors doubled the risk), as well as worse mean deviation and older age. Progression risk decreased by about 10% with each millimeter of mercury of IOP reduction from baseline to the first follow-up visit (HR = 0.90 per millimeter of mercury decrease; 95% CI, 0.86-0.94). The first IOP at that visit (3 months' follow-up) was also related to progression (HR = 1.11 per millimeter of mercury higher; 95% CI, 1.06-1.17), as was the mean IOP at follow-up (HR = 1.13 per millimeter of mercury higher; 95% CI, 1.07-1.19). The percent of patient follow-up visits with disc hemorrhages was also related to progression (HR = 1.02 per percent higher; 95% CI, 1.01-1.03). No other factors were identified., Conclusions: Patients treated in the EMGT had half of the progression risk of control patients. The magnitude of initial IOP reduction was a major factor influencing outcome. Progression was also increased with higher baseline IOP, exfoliation, bilateral disease, worse mean deviation, and older age, as well as frequent disc hemorrhages during follow-up. Each higher (or lower) millimeter of mercury of IOP on follow-up was associated with an approximate 10% increased (or decreased) risk of progression.

Objective: To provide the results of the Early Manifest Glaucoma Trial, which compared the effect of immediately lowering the intraocular pressure (IOP), vs no treatment or later treatment, on the progression of newly detected open-angle glaucoma., Design: Randomized clinical trial., Participants: Two hundred fifty-five patients aged 50 to 80 years (median, 68 years) with early glaucoma, visual field defects (median mean deviation, -4 dB), and a median IOP of 20 mm Hg, mainly identified through a population screening. Patients with an IOP greater than 30 mm Hg or advanced visual field loss were ineligible., Interventions: Patients were randomized to either laser trabeculoplasty plus topical betaxolol hydrochloride (n = 129) or no initial treatment (n = 126). Study visits included Humphrey Full Threshold 30-2 visual field tests and tonometry every 3 months, and optic disc photography every 6 months. Decisions regarding treatment were made jointly with the patient when progression occurred and thereafter., Main Outcome Measures: Glaucoma progression was defined by specific visual field and optic disc outcomes. Criteria for perimetric progression were computer based and defined as the same 3 or more test point locations showing significant deterioration from baseline in glaucoma change probability maps from 3 consecutive tests. Optic disc progression was determined by masked graders using flicker chronoscopy plus side-by-side photogradings., Results: After a median follow-up period of 6 years (range, 51-102 months), retention was excellent, with only 6 patients lost to follow-up for reasons other than death. On average, treatment reduced the IOP by 5.1 mm Hg or 25%, a reduction maintained throughout follow-up. Progression was less frequent in the treatment group (58/129; 45%) than in controls (78/126; 62%) (P =.007) and occurred significantly later in treated patients. Treatment effects were also evident when stratifying patients by median IOP, mean deviation, and age as well as exfoliation status. Although patients reported few systemic or ocular conditions, increases in clinical nuclear lens opacity gradings were associated with treatment (P =.002)., Conclusions: The Early Manifest Glaucoma Trial is the first adequately powered randomized trial with an untreated control arm to evaluate the effects of IOP reduction in patients with open-angle glaucoma who have elevated and normal IOP. Its intent-to-treat analysis showed considerable beneficial effects of treatment that significantly delayed progression. Whereas progression varied across patient categories, treatment effects were present in both older and younger patients, high- and normal-tension glaucoma, and eyes with less and greater visual field loss.

Background: The risk of open-angle glaucoma (OAG) may be related to low blood pressure (BP) relative to intraocular pressure (IOP), ie, to low perfusion pressure (PP). Alternatively, systemic hypertension may increase OAG risk., Objective: To clarify these possible relationships by evaluating hypertension and PP (where PP = BP - IOP) as risk factors for incident OAG in a black population., Design: Population-based cohort study (85% participation); simple random sample of residents of Barbados, West Indies, aged 40 years and older., Participants: Two thousand nine hundred eighty-nine black participants at risk; 67 developed OAG after 4 years (2.2% incidence)., Main Outcome Measure: Adjusted relative risk (RR) of OAG from logistic regression analyses., Results: The 4-year risk increased markedly with baseline IOP. With an IOP less than or equal to 17 mm Hg, incidence was 0.7%, increasing to 18.3% with IOP greater than 25 mm Hg, for a 25-fold increase in RR. However, OAG developed throughout the IOP range and two thirds of incident cases had baseline IOP less than 25 mm Hg. Baseline hypertension was associated with a halving of the RR of OAG (RR, 0.49; 95% confidence interval [CI], 0.29-0.85); the RR also tended to decrease as systolic BP increased (P =.07). Consistent with these findings, a lower baseline PP increased RR (systolic PP <101 mm Hg, 2.6 [95% CI, 1.3-4.9]; diastolic PP <55 mm Hg, 3.2 [95% CI, 1.6-6.6]; mean PP <42 mm Hg, 3.1 [95% CI, 1.6-6.0])., Conclusions: As baseline IOP increased, the risk of OAG substantially increased. In contrast, persons with systemic hypertension at baseline had half the RR, suggesting that hypertension does not increase (and may decrease) the 4-year risk of OAG. Lower PP at baseline increased RR approximately 3-fold, a result consistent with the vascular hypothesis of OAG pathogenesis.

Objective: To describe the distribution and risk factors for pterygium in the predominantly black population of the Barbados Eye Study, which was based on a random sample of Barbadian-born citizens between the ages of 40 and 84 years., Methods: The standardized protocol included ophthalmic and other measurements, automated perimetry, lens gradings, fundus photography, and a detailed interview. A 10% systematic sample of participants and those meeting specific criteria also received a comprehensive ophthalmologic evaluation., Results: The Barbados Eye Study included 4709 participants, of whom 2978 were referred for an ophthalmologic evaluation and 2781 (93%) completed the examination. Cases of pterygium were found among 23.4% of 2617 black, 23.7% of 97 mixed (black and white), and 10.2% of 59 white participants examined. In addition to African ancestry, logistic regression analyses indicated a positive association between pterygium and age (odds ratio [OR], 1.01; 95% confidence interval [CI], 1.00-1.02), fewer years of education (OR, 1.43; 95% CI, 1.01-2.03), and an outdoor job location (OR, 1.87; 95% CI, 1.52-2.29). Having a darker skin complexion (OR, 0.66; 95% CI, 0.52-0.83), always using sunglasses outdoors (OR, 0.18; 95% CI, 0.06-0.59), and the use of prescription glasses (OR, 0.75; 95% CI, 0.60-0.93) were protective factors., Conclusions: Approximately one quarter of the black participants examined had pterygia, a frequency that was 2.5 to 3 times higher than among whites in the Barbados Eye Study and elsewhere. Pterygium was almost twice as frequent among persons who worked outdoors but was only one fifth as likely among those who always used sunglasses outdoors. Educational interventions to modify these potential exposures may assist in preventing pterygium.

Objective: To measure the 4-year risk of open-angle glaucoma (OAG) in a black population., Design: Population-based cohort study with 4 years of follow-up., Setting: Simple random sample of residents of Barbados, West Indies, aged 40 years or older., Participants: A total of 3427 members of the cohort (85% of those eligible)., Main Outcome Measure: Development of glaucoma visual field defects and optic disc damage, confirmed by automated perimetry, independent fundus photographic gradings, and standardized ophthalmologic examinations., Results: The 4-year risk of OAG in black participants was 2.2% (95% confidence interval, 1.7%-2.8%), based on 67 newly developed cases of OAG. Incidence rates increased from 1.2% at ages 40 to 49 years to 4.2% at ages of 70 years or more, tending to be higher in men than women (2.7% vs 1.9%). About half of the incident cases were undiagnosed previously, and the rest were receiving OAG treatment. Of the 67 new cases of OAG, 32 had intraocular pressure of 21 mm Hg or less at baseline (1.2% incidence) and 35 had higher pressures (9% incidence). Risk was highest among persons classified as having suspect OAG at baseline (26.1%), followed by those with ocular hypertension (4.9%) and lowest in the remaining population (0.8%)., Conclusions: This longitudinal study provides new information on OAG risk, as well as the first incidence measurement in a black population. Although intraocular pressure increased risk, about half of the new cases had baseline pressures of 21 mm Hg or less. Results substantiate the high OAG risk in the population of African origin, especially in older adults; the relative role of intraocular pressure; and the considerable underdetection of new disease after 4 years of follow-up.

Objectives: To describe a case-control study of risk factors for neovascular and non-neovascular age-related macular degeneration (AMD) and to present findings on associations with systemic hypertension and cardiovascular disease., Methods: Participants with and without neovascular and non-neovascular AMD were recruited from 11 ophthalmology practices in the New York, NY, metropolitan area. Comprehensive data collection included (1) a standardized interview, (2) blood pressure measurements, and (3) blood samples. Cases and controls were classified from fundus photograph gradings. Polychotomous logistic regression analyses were used to evaluate associations., Results: Classification of 1222 sets of available photographs resulted in the inclusion of a neovascular case group (n = 182), a non-neovascular case group (n = 227), and a control group (n = 235). Neovascular AMD was positively associated with diastolic blood pressure greater than 95 mm Hg (odds ratio [OR] = 4.4), self-reported use of potent antihypertensive medication (OR = 2.1), physician-reported history of hypertension (OR = 1.8), use of antihypertensive medication (OR = 2.5), combinations of self-reported and physician-reported data on hypertension and its treatment (OR = 1. 7), high-density lipoprotein level (OR = 2.3), and dietary cholesterol level (OR = 2.2). Non-neovascular AMD was unrelated to hypertension or cholesterol level. No associations were found between either AMD type and other definitions of hypertension or other cardiovascular disease., Conclusions: These findings suggest that neovascular AMD is associated with moderate to severe hypertension, particularly among patients receiving antihypertensive treatment. They also support the hypotheses that neovascular and non-neovascular AMD may have a different pathogenesis and that neovascular AMD and hypertensive disease may have a similar underlying systemic process.

Objective: To evaluate the demographic, medical, ocular, familial, and other factors possibly associated with intraocular pressure (IOP) in a black population, after excluding persons with any type of glaucoma., Design: The Barbados Eye Study was a population-based study of a random sample of residents of Barbados, West Indies, aged 40 to 84 years., Participants: A subset of the Barbados Eye Study population consisting of 3752 black Barbados Eye Study participants without glaucoma., Data Collection: A standardized protocol included applanation tonometry and other ocular data, blood pressure measurements, anthropometry, complexion pigmentation gradings, and a comprehensive interview., Main Outcome Measure: Intraocular pressure was based on the average of 3 measurements at the Barbados Eye Study visit. Multiple linear regression was used to evaluate factors associated with IOP., Results: Systolic blood pressure (or hypertension), diabetes history, and age were the major factors positively associated with IOP (P<.01). Other positively related factors were female gender, darker complexion, pulse rate, higher body mass, seasonality, family history of glaucoma, current alcohol use, and current smoking. These factors explained 10% of the variation in IOP., Conclusions: By identifying risk factors, these results define specific subgroups most likely to have an elevated IOP. The high IOP in this population may be linked to the high prevalence of hypertension and diabetes. Aside from age and a family history of glaucoma, none of the risk factors for high IOP evaluated in this study was similar to those associated with open-angle glaucoma.

Objective: To provide data on the distribution of intraocular pressure (IOP) in a predominantly black population, which has a high prevalence of open-angle glaucoma., Design: Population-based prevalence study., Setting and Participants: Participants (N = 4601) (age range, 40-84 years) who had undergone applanation tonometry measurements in the Barbados Eye Study. Self-reported race was 93% black, 4% mixed (black and white), and 3% white or other., Data Collection: A standardized protocol included applanation tonometry and other ocular measurements, fundus photography, demographic data, and an interview., Main Outcome Measures: The average of 3 IOP measurements at the Barbados Eye Study visit was used to compare IOP by self-reported race. Descriptive data on IOP by age, sex, glaucoma status, and cup-disc ratio were examined in the black population., Results: The IOP was highest in the population of African origin. The mean (+/-SD) IOP values for black, mixed, and white participants were 18.7 +/- 5.2, 18.2 +/- 3.8, and 16.5 +/- 3.0 mm Hg, respectively. An IOP greater than 21 mm Hg was present in 18.4%, 13.6%, and 4.6% of the black, mixed, and white participants, respectively. In analyses that were adjusted for age, sex, and glaucoma status, such values were 5 times as likely in black than white participants and 3.5 times as likely in mixed race participants (P < .01). Among the black participants, the mean IOP increased approximately 1 mm Hg for every increase in 10 years of age. After excluding persons with any type of glaucoma, suspected glaucoma, or a history of glaucoma treatment, women had significantly (P < .01) higher IOP values; however, no significant IOP trends by sex were evident in the group with glaucoma. The IOP was also positively associated (P < .05) with vertical cup-disc ratios. After 2 visits, the IOP remained 21 mm Hg or less in 21% of the persons with glaucoma vs 64% of those without glaucoma., Conclusions: In the black participants, the IOP was higher than in the white participants. The IOP was also associated with age and cup-disc ratios. The results showed that open-angle glaucoma and a high IOP alone have a different distribution by sex; although open-angle glaucoma was more frequent in men, ocular hypertension was more frequent in women. These data have implications for the detection and causation of open-angle glaucoma in this high-risk population.

Objective: To present population-based data on type and extent of age-related lens opacities in the predominantly black population of the Barbados Eye Study., Design: Prevalence study., Setting and Participants: The Barbados Eye Study included 4709 participants (84% of those eligible), who were identified from a random sample of Barbadian-born citizens aged 40 to 84 years., Data Collection: Lens gradings at the slit lamp, obtained with the use of the Lens Opacities Classification System II., Main Outcome Measure: Prevalence of posterior subcapsular, nuclear, and cortical opacities (defined as a grade > or = 2 in either eye), as well as prevalence of any lens changes (including history of previous cataract surgery and/or cataract too advanced to grade)., Results: Overall, 41% of the Barbados Eye Study population had any lens changes, including 3% with aphakia or an intraocular lens. Among the population of African descent, cortical opacities (34%) were most prevalent, followed by nuclear (19%) and posterior subcapsular (4%) opacities. Prevalence of all opacity types increased with age (P < .001). Cortical and nuclear opacities were more frequent in women than men. When prevalence of a single kind of opacity was considered, 21% of participants had cortical only, 6% had nuclear only, and 0.4% had posterior subcapsular only; 13% had mixed opacities. Visual acuity loss to worse than 20/40 in the more affected eye was present in 48%, 26%, and 18% of nuclear only, posterior subcapsular only, and cortical only types, respectively, and in 53% of mixed opacities., Conclusions: The Barbados Eye Study provides the first prevalence data on different types of lens opacities in a large, predominantly black population. Whereas nuclear opacities are most common in white populations, cortical opacities were the most frequent type in the Barbados Eye Study, a finding of possible etiologic relevance. Other results highlight a higher frequency of opacities in women than men and a high prevalence of visual acuity loss in affected eyes.

Objective: To evaluate the association of open-angle glaucoma (OAG) with ABO, Rh and Duffy blood groups in the population-based Barbados Eye Study., Design: Case-control study., Setting and Participants: A subset of black Barbados Eye Study participants, which included 199 OAG cases and 1063 controls., Data Collection: ABO, Rh and Duffy blood groups were determined as part of a comprehensive study visit, which included assessment for OAG through perimetry, fundus photography, and ophthalmologic examination., Outcome Measures: Comparison of blood groups between OAG cases and nonOAG controls, expressed as odds ratio and 95% confidence intervals., Results: Associations were found with the Duffy Fya+ group, which is more frequent in white than black populations. In Mantel-Haenszel analyses, OAG was positively associated with Duffy Fya+ in men (odds ratio, 2.67; confidence interval, 1.52 to 4.69) and in persons with intraocular pressure more than 21 mm Hg (odds ratio, 3.32; confidence interval, 1.49 to 7.38). Logistic regression analyses confirmed these findings (interaction of Duffy Fya+ and male gender, P = .01; interaction of Duffy Fya+ and intraocular pressure, P = .04). No associations between OAG and the ABO or Rh blood groups were seen., Conclusions: The associations with Duffy Fya+, which had not been reported previously in a black population, support the involvement of genetic factors in OAG. However, the lack of association between OAG and blood group markers of African ancestry is inconsistent with a genetic explanation for the differences in OAG prevalence between blacks and whites. Our findings suggest gene-environment interactions in OAG, to be explored by further studies of OAG and Fy markers by racial group and gender.

Objective: To evaluate associations with biochemical indicators of nutritional and other risk factors in the Lens Opacities Case-Control Study., Design: Case-control study., Setting and Participants: The Lens Opacities Case-Control Study determined risk factors for cortical, nuclear, and posterior subcapsular opacities among 1380 participants aged 40 to 79 years., Data Collection: Vitamin E, selenium, and biochemistry profile determinations were performed on all patients; red blood cell enzymes and amino acids were measured in systematic samples of about 25% of the Lens Opacities Case-Control Study population., Outcome: Laboratory test values in cases and controls were compared and expressed as odds ratios and 95% confidence intervals., Results: In polychotomous logistic regression analyses controlling for age and sex, the risk of opacities was reduced to less than one half in persons with higher levels of vitamin E (odds ratio, 0.44 for nuclear opacities), albumin-globulin ratio (odds ratio, 0.41 for mixed opacities), or iron (odds ratio, 0.43 for cortical opacities); higher uric acid levels increased risk (odds ratio, 1.74 for mixed opacities). Persons with opacities were twice as likely to have high glutathione reductase activity (with flavin adenine dinucleotide), which suggests low riboflavin status (odds ratio, 2.13). Most odds ratios for amino acids were under unity and were significantly decreased for glycine (0.36) and aspartic acid (0.31)., Conclusions: Lens opacities were associated with lower levels of riboflavin, vitamin E, iron, and protein nutritional status. Higher levels of uric acid increased risk of mixed opacities. The findings for riboflavin, vitamin E, iron, and uric acid are compatible with the dietary intake and medical history results of the Lens Opacities Case-Control Study.

Objective: To evaluate risk factors for open-angle glaucoma among black participants in the Barbados Eye Study., Design: Population-based study of demographic, medical, ocular, familial, and other factors possibly related to open-angle glaucoma., Setting and Participants: The Barbados Eye Study included 4709 Barbados residents identified by a simple random sample of Barbadian-born citizens, 40 to 84 years of age; participation was 84%. This report is based on the 4314 black participants examined at the study site; 302 (7%) met the Barbados Eye Study criteria for open-angle glaucoma., Data Collection: A standardized protocol included applanation tonometry, Humphrey perimetry, fundus photography, blood pressure, anthropometry, and an interview. An ophthalmologic examination was performed for participants who met specific criteria., Main Outcome Measures: Open-angle glaucoma was defined by the presence of both characteristic visual field defects and optic disc damage. Association of open-angle glaucoma with specific factors was evaluated in logistic regression analyses., Results: Age, male gender, high intraocular pressure, and family history of open-angle glaucoma were major risk factors; the latter association was stronger in men than women. Lean body mass and cataract history were the only other factors related to open-angle glaucoma. Although hypertension and diabetes were common in Barbados Eye Study participants, they were unrelated to the prevalence of open-angle glaucoma. However, associations were found with low diastolic blood pressure-intraocular pressure differences and low systolic and diastolic blood pressure/intraocular pressure ratios., Conclusions: In the Barbados Eye Study black population, persons most likely to have open-angle glaucoma were older men and had a family history of open-angle glaucoma, high intraocular pressure, lean body mass, and cataract history. These results suggest the importance of possible genetic or familial factors in open-angle glaucoma. The role of vascular risk factors is consistent with our finding of low blood pressure to intraocular pressure relationships, but the results could be explained by the high intraocular pressure in open-angle glaucoma.

Objective: To report on the frequency of features of age-related macular degeneration in a black population based on fundus photograph gradings., Design: Population-based study., Setting: Barbados, West Indies., Study Population: Residents of Barbados, selected by a random sample of Barbados-born citizens, aged 40 to 84 years., Main Outcome Measure: Gradings from 30 degrees stereoscopic macular photographs., Results: Black participants (n = 3444) completed examinations at the study site and had gradable macular photographs in both eyes. Drusen larger than 63 microns occurred with comparable frequency in men and women. The frequency of small drusen decreased with age, while medium and large drusen were more common in older participants. Frequencies of all age-related macular degeneration-related characteristics were similar for men and women except for small drusen, which occurred more commonly in women. Confluent drusen and pigment atrophy also increased significantly with age. Exudative features occurred in 0.5% of the participants., Conclusions: This study provides population-based data on the frequency of features of age-related macular degeneration based on photographic gradings of a black population. Features of early age-related macular degeneration were common, but appeared at a lower frequency than has been reported for white populations. Exudative disease was infrequent, occurring in about one of 200 participants.

Objective: To describe the design of the Barbados Eye Study and report on the prevalence of open angle glaucoma (OAG) in a predominantly black study population., Design: Population-based prevalence study., Setting and Participants: Residents of Barbados, West Indies, identified from a simple random sample of Barbadian-born citizens 40 through 84 years old., Data Collection: Participants had a comprehensive study visit that included automated perimetry, applanation tonometry, and fundus photography; persons with specific examination findings, as well as a 10% sample of participants, were referred for an ophthalmologic examination and additional tests., Outcome: A diagnosis of OAG required both visual field and optic disc criteria for glaucoma damage after excluding other causes., Results: The 4709 participants (83.5% of those eligible) had demographic characteristics that were similar to the census population. Of the 4631 participants who were tested at the study site, 95% completed Humphrey automated perimetry and 97% had photographic or clinical disc gradings; 93% of those referred completed the ophthalmologic examination. In this adult population, the prevalence of OAG by self-reported race was 7.0% (302/4314) in black, 3.3% (6/184) in mixed-race, and 0.8% (1/133) in white or other participants. In black and mixed-race participants, the prevalence reached 12% at age 60 years and older and was higher in men (8.3%) than in women (5.7%), with an age-adjusted male-female ratio of 1.4. In addition, over 3% of the participants were classified as having suspect OAG., Conclusions: To our knowledge, the Barbados Eye Study is the largest glaucoma study ever conducted in a black population and identified more people with OAG than did any previous population study. The prevalence of OAG was high, especially at older ages and in men. Among participants 50 years old or older, one in 11 had OAG, and prevalence increased to one in six at age 70 years or older. The results highlight the public health importance of OAG in the Afro-Caribbean region and have implications for other populations.

Objective: To compare the use of clinical examination and fundus photograph gradings in detecting diabetic retinopathy in a population that includes persons with and without diabetes., Design: Population-based epidemiologic study., Setting: Sir Winston Scott Polyclinic, Bridgetown, Barbados, West Indies., Participants: Subset of a random sample of the country's population aged 40 to 86 years., Results: Among 1168 black persons with fundus photograph evaluations, ophthalmologic examinations, diabetes history, and glycated hemoglobin data, 21% reported a history of diabetes; 9.5% had definite diabetes (glycated hemoglobin > 11.5%); and 13.3% had a diabetes history and glycated hemoglobin value less than or equal to 11.5%. The frequency of diabetic retinopathy in this group was 7.7% (90/1168) by clinical examination, 8.7% (102/1168) by photograph gradings, and 6.7% (78/1168) by both methods., Conclusions: These results suggest that in certain populations that include diabetics and nondiabetics, a clinical examination by an ophthalmologist will detect most cases of diabetic retinopathy identified by disc and macula photographs read by skilled graders. However, it will lead to an underestimate of prevalence. Staff availability and cost, issues not examined in this study, should determine which approach is selected.

Objective: To develop the Lens Opacities Classification System III (LOCS III) to overcome the limitations inherent in lens classification using LOCS II. These limitations include unequal intervals between standards, only one standard for color grading, use of integer grading, and wide 95% tolerance limits., Design and Results: The LOCS III contains an expanded set of standards that were selected from the Longitudinal Study of Cataract slide library at the Center for Clinical Cataract Research, Boston, Mass. It consists of six slit-lamp images for grading nuclear color (NC) and nuclear opalescence (NO), five retroillumination images for grading cortical cataract (C), and five retroillumination images for grading posterior subcapsular (P) cataract. Cataract severity is graded on a decimal scale, and the standards have regularly spaced intervals on a decimal scale. The 95% tolerance limits are reduced from 2.0 for each class with LOCS II to 0.7 for nuclear opalescence, 0.7 for nuclear color, 0.5 for cortical cataract, and 1.0 for posterior subcapsular cataract with the LOCS III, with excellent interobserver agreement., Conclusion: The LOCS III is an improved LOCS system for grading slit-lamp and retroillumination images of age-related cataract.

The Lens Opacities Case-Control Study evaluated risk factors for age-related nuclear, cortical, posterior subcapsular, and mixed cataracts. The 1380 participants were ophthalmology outpatients, aged 40 to 79 years, classified into the following groups: posterior subcapsular only, 72 patients; nuclear only, 137 patients; cortical only, 290 patients; mixed cataract, 446 patients; and controls, 435 patients. In polychotomous logistic regression analyses, low education increased risk (odds ratio [OR] = 1.46) and regular use of multivitamin supplements decreased risk (OR = 0.63) for all cataract types. Dietary intake of riboflavin, vitamins C, E, and carotene, which have antioxidant potential, was protective for cortical, nuclear, and mixed cataract; intake of niacin, thiamine, and iron also decreased risk. Similar results were found in analyses that combined the antioxidant vitamins (OR = 0.40) or considered the individual nutrients (OR = 0.48 to 0.56). Diabetes increased risk of posterior subcapsular, cortical, and mixed cataracts (OR = 1.56). Oral steroid therapy increased posterior subcapsular cataract risk (OR = 5.83). Females (OR = 1.51) and nonwhites (OR = 2.03) were at increased risk only for cortical cataract. Risk factors for nuclear cataract were a nonprofessional occupation (OR = 1.96), current smoking (OR = 1.68), body mass index (OR = 0.76), and occupational exposure to sunlight (OR = 0.61). Gout medications (OR = 2.48), family history (OR = 1.52), and use of eyeglasses by age 20 years, which is an indicator of myopia (OR = 1.44), increased risk of mixed cataract. The results support a role for the nutritional, medical, personal, and other factors in cataractogenesis. The potentially modifiable factors suggested by this study merit further evaluation.

A simple system, based on standard photographs, has been developed to classify lens opacities. The system allows the definition of cataract cases and noncases according to the location of lens opacification (nuclear, cortical, posterior subcapsular) and its extent (early or more advanced). Evaluation of the system has shown good to excellent reproducibility for clinical and photographic classifications. Comparisons of clinical and photograph-derived gradings has shown generally good agreement in classifying the presence and type of cataract; this agreement is highest for nuclear cataract. Photographic gradings of posterior subcapsular and, to a lesser degree, cortical opacities tend to underestimate the extent of opacification found by clinical gradings. The Lens Opacities Case-Control Study system is simple, reproducible, and easy to implement; it is offered for use in case-control and other cross-sectional studies of cataract with compatible classification goals.

The Lens Opacities Classification System, version II (LOCS II), uses a set of colored slit-lamp and retroillumination transparencies to grade different degrees of nuclear, cortical, and subcapsular cataract. The system uses four nuclear standards for grading nuclear opalescence and color, five cortical standards, and four subcapsular standards. The LOCS II can be used to grade patients' cataracts at the slit lamp or to grade slit-lamp and retroillumination photographs; it is easy to learn and can be applied consistently by different observers. We obtained very good interobserver reproducibility of the clinical gradings at the slit lamp, excellent intraobserver reproducibility, very good to excellent interobserver reproducibility of photographic gradings, and good agreement between clinical and photographic gradings. The LOCS II is potentially useful for both cross-sectional and longitudinal studies of cataract.

The Lens Opacities Classification System (LOCS) is a simple system for classifying age-related human lens opacities at the slit lamp or in retroilluminated and slit-lamp photographs. The system employs a set of standard Neitz CTR retroilluminated black-and-white photographs for classification of cortical and posterior subcapsular cataracts and a single color slit-lamp photograph for classification of nuclear color and opalescence. We present a detailed description of the system.