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The prevalence of open-angle glaucoma is believed to be very high among West Indian blacks. To begin investigating the prevalence and risk factors for glaucoma and other eye diseases in Barbados, WI, a pilot study was conducted. The pilot project identified a stratified, random national sample of 300 persons over 35 years of age who were invited to participate in an ophthalmic examination and an interview. Of those contacted 89% were eligible and 95% of these agreed to participate. The overall glaucoma prevalence in the participants was 6%; it was 13% among black and mixed persons over 54 years. Age related cataract, hypertension, and diabetes were frequent findings. Although the sample size of the pilot project is small, the results suggest a high prevalence of glaucoma in Barbados, a finding that merits further study. [ABSTRACT FROM PUBLISHER]

Background: This study evaluated the association of age-related lens opacities with the use of nutritional supplements and demographic factors among 4314 black participants (> or = 40 years) in the population-based Barbados Eye Study.Methods: Lenses were classified at the slit lamp by the Lens Opacities Classification System II (LOCS II); a score > or = 2 was used to define the presence of gradable lens opacities, by type. Lens changes also included prior cataract surgery or cataract too advanced to grade. Associations with risk factors were evaluated by logistic regression analyses.Results: The study identified 1800 individuals with lens changes in at least one eye; 229 had nuclear opacities only; 851 had cortical opacities only. Older age and indicators of lower socioeconomic status (low education and/or non-professional occupation), were positively associated with both nuclear (odds ratio [OR] = 1.90) and cortical (OR = 1.47) opacities. Women had an increased risk of cortical opacities (OR = 1.41). Regular users of nutritional supplements were less likely to have lens changes (OR = 0.78) and, specifically, cortical opacities (OR = 0.77). The association with nutritional supplements was present in those < 70 years, but not at older ages.Conclusions: The study supports the association of lower socioeconomic status with lens changes, including nuclear and cortical lens opacities. The findings also suggest that regular users of nutritional supplements have a one-fourth lower risk of lens changes and particularly, of cortical opacities; a result seen at ages under 70 years. The associations with potentially modifiable factors indicate the need for further evaluations, given the high prevalence of lens opacities. [ABSTRACT FROM AUTHOR]

Background: Alcohol use is associated with breast cancer in many epidemiological studies. Most, however, have measured risk from recent consumption patterns, and only a few include analyses for duration of drinking or age that a woman started to drink. The authors studied the effect of these variables, as well as of recent alcohol consumption patterns, on breast cancer risk.Methods: Data from a large case-control study conducted in Long Island, New York from 1 January 1984 to 31 December 1986 were used. A total of 1214 women aged 20-79 years with incident breast cancer were interviewed. A control was selected for each case from driver's license files, and matched on age and county of residence. Alcohol consumption was measured as: ever versus never, grams of alcohol per day, age started drinking, and total years drinking.Results: After adjustment for breast cancer risk factors, the odds ratio for ever versus never drinking was 1.40 (95% confidence interval [CI] 1.09-1.79); odds ratios for > 0-5 and > or = 5 grams of alcohol use per day, as compared to nondrinkers, were 1.29 (95% CI: 1.00-1.65) and 1.46 (95% CI: 1.13-1.89), respectively. Age when drinking began was not related to breast cancer risk, but the greater the total years of drinking, up to 40 years (odds ratio 1.48, 95% CI: 1.13-1.93), the greater the risk. However, when grams per day and duration of drinking were simultaneously included in the multivariate model, duration was not important as a risk factor. This suggests that intensity of drinking may be the important factor for breast cancer risk. After covariate adjustment, risk from alcohol intake did not differ between pre- and postmenopausal women. [ABSTRACT FROM AUTHOR]

The relationship between oestrogen replacement therapy and breast cancer risk was examined based on data obtained from a population-based case-control study of breast cancer on Long Island, New York, USA. Cases were defined as female residents of two Long Island counties, aged 20–79, who were diagnosed with breast cancer between 1 January 1984 and 31 December 1986. Age- and county-matched controls were selected from driver's licence files. Among all postmenopausal women, there was no significant association between ever-use of hormones to treat menopausal symptoms and breast cancer risk. There was also no significant positive association in any subgroup defined by type of menopause (natural, hysterectomy with at least one ovary intact, bilateral oophorectomy) or age at menopause. Additionally, there was no increasing trend in risk with duration of use either overall or in any subgroup, nor was there an effect at any interval since last use. A significant elevation in risk was observed in women with 10–19 years since first exposure, which was concentrated in women with a natural menopause or hysterectomy with at least one ovary remaining, and women aged >45 at menopause. Results of logistic regression analysis revealed no important confounding by any of several established breast cancer risk factors. However, a significant interaction was observed between body mass index (BMI) and oestrogen use, with an effect of oestrogen use being seen only in the thinnest tercile. Although biologically plausible explanations for this finding exist, the effect of chance cannot be ruled out. [ABSTRACT FROM PUBLISHER]

Alcohol and tobacco consumption are closely correlated and published results on their association with breast cancer have not always allowed adequately for confounding between these exposures. Over 80% of the relevant information worldwide on alcohol and tobacco consumption and breast cancer were collated, checked and analysed centrally. Analyses included 58,515 women with invasive breast cancer and 95,067 controls from 53 studies. Relative risks of breast cancer were estimated, after stratifying by study, age, parity and, where appropriate, women's age when their first child was born and consumption of alcohol and tobacco. The average consumption of alcohol reported by controls from developed countries was 6.0 g per day, i.e. about half a unit/drink of alcohol per day, and was greater in ever-smokers than never-smokers, (8.4 g per day and 5.0 g per day, respectively). Compared with women who reported drinking no alcohol, the relative risk of breast cancer was 1.32 (1.19-1.45, P<0.00001) for an intake of 35-44 g per day alcohol, and 1.46 (1.33-1.61, P<0.00001) for >/=45 g per day alcohol. The relative risk of breast cancer increased by 7.1% (95% CI 5.5-8.7%; P<0.00001) for each additional 10 g per day intake of alcohol, i.e. for each extra unit or drink of alcohol consumed on a daily basis. This increase was the same in ever-smokers and never-smokers (7.1% per 10 g per day, P<0.00001, in each group). By contrast, the relationship between smoking and breast cancer was substantially confounded by the effect of alcohol. When analyses were restricted to 22 255 women with breast cancer and 40 832 controls who reported drinking no alcohol, smoking was not associated with breast cancer (compared to never-smokers, relative risk for ever-smokers=1.03, 95% CI 0.98-1.07, and for current smokers=0.99, 0.92-1.05). The results for alcohol and for tobacco did not vary substantially across studies, study designs, or according to 15 personal characteristics of the women; nor were the findings materially confounded by any of these factors. If the observed relationship for alcohol is causal, these results suggest that about 4% of the breast cancers in developed countries are attributable to alcohol. In developing countries, where alcohol consumption among controls averaged only 0.4 g per day, alcohol would have a negligible effect on the incidence of breast cancer. In conclusion, smoking has little or no independent effect on the risk of developing breast cancer; the effect of alcohol on breast cancer needs to be interpreted in the context of its beneficial effects, in moderation, on cardiovascular disease and its harmful effects on cirrhosis and cancers of the mouth, larynx, oesophagus and liver.

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.

The majority of genetic studies on open-angle glaucoma (OAG) have been conducted in primarily white populations, with investigations of inheritance patterns largely based on self-reported information. The Barbados Family Study of Open-Angle Glaucoma (BFSG) is the first study to investigate the transmission pattern(s) for OAG in a predominantly black population, based on standardized examinations. Each BFSG participant received a comprehensive examination including anthropometric and other measurements, best-corrected visual acuity, perimetry, tonometry, lens gradings, fundus photography, venipuncture, an extensive interview including ocular, medical and family history information and a comprehensive ophthalmologic evaluation. Conservative criteria were used to define glaucoma status, including the presence of both visual field defects and optic disc damage. The study included 207 OAG-affected probands (median age: 68 years) and 1,056 of their relatives (median age: 47 years). Among the relatives examined 10% (n = 106) had OAG and 13% (n = 141) had probable OAG. Segregation analyses were performed to determine the mode of inheritance for glaucoma in these families. The results indicate that transmission of OAG or probable OAG is most likely due to a major codominant gene. Both age and gender are shown to be significant factors as well; with an increase in risk being associated with each year of age over 54 years and an increase in risk for all ages and genotypes observed in males. These analyses do not, however, preclude the possible existence of an environmental component or other genetic determinants in OAG. Further evidence for the existence of a major gene may be obtained by additional follow-up of the relatively young cohort of relatives, as well as ongoing linkage analyses., (Copyright 2001 Wiley-Liss, Inc.)

Incidence data on open-angle glaucoma (OAG) are limited and difficult to obtain. To date, few studies have reported incidence directly measured from population-based cohorts. Other reported estimates have been derived indirectly from age-specific prevalence by using several assumptions, and their validity is unknown. To the authors' knowledge, this report presents the first comparison of observed versus indirect estimates of OAG incidence based on data from the population-based Barbados Incidence Study of Eye Diseases (1992-1997) (n = 3,427; 85% participation). The observed 4-year incidence of OAG was 1.2% (95% confidence interval (CI): 0.6, 2.1%) at ages 40-49 years, 1.5% (95% CI: 0.8, 2.5%) at ages 50-59 years, 3.2% (95% CI: 2.0, 4.8%) at ages 60-69 years, and 4.2% (95% CI: 2.6, 6.3%) in persons at ages 70 or more years. When incidence was calculated from the prevalence data, power function fitting achieved a closer approximation to observed incidence than did logistic curve fitting. Calculated incidence rates for each group were similar when assuming mortality that was equal (incidence rate = 0.7, 1.3, 2.3, and 4.8%) or differential (incidence rate = 0.7, 1.2, 2.4, and 4.8%). Other nonlogistic approaches also increased the resemblance of observed and calculated estimates. In the absence of longitudinal data, reasonably valid incidence estimates of OAG were obtained from available prevalence data. These estimation techniques can be useful when OAG incidence estimates are required for research or public health purposes.

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.

Purpose: Recruiting participants is a major challenge for population studies. We present the recruitment methods followed by the Diabetic Retinopathy Awareness Program (DRAP), a community-based, randomized, masked, controlled trial to meet and exceed its sample size goals., Methods: A county-wide multi-media promotional campaign to recruit and enroll participants in the trial was planned and executed from October 1993 through April 1994, with the assistance of the local news media and community and professional groups. A toll-free 800 number recruitment line was established, and postage-paid recruitment postcards distributed. The trial was designed to examine whether a mailed educational intervention could increase compliance with vision care guidelines among persons with diabetes in the community., Results: A total of 2308 persons with diabetes were interviewed for eligibility and 813 enrolled in the intervention trial, exceeding the original recruitment goals of 1800 and 600, respectively. Those who completed the enrollment interview reflected county demographics. During recruitment, newspaper, television and radio stories featured the study; pharmacies and physician offices displayed study materials; public service announcements appeared in local print and broadcast media. The largest single recruitment response was a local television news report, followed by a newspaper story., Conclusions: These experiences substantiate the need for a comprehensive coordinated approach, using planned multiple sources, to achieve recruitment success. By engaging the lay and professional communities along with the media, recruitment costs can be kept to a minimum. Participant costs can be minimized by employing a toll-free number and eliminating study participant travel, thus allowing for inclusion of traditionally underserved populations. This approach is applicable to other studies, where community-based participation is desired.

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.

Purpose: Several statements have been issued to the effect that no consistent, significant link has been demonstrated between cancer and electromagnetic fields (EMF). However, there continues to be much interest in a possible association with breast cancer, in part because breast cancer risk is substantially higher in industrialized countries than in other areas, and electric power generation and consumption is one of the hallmarks of industrialized societies. In 1987, Stevens proposed a biological mechanism whereby two products of electric power generation, EMF and light at night, might contribute to mammary carcinogenesis through inhibition of melatonin., Methods: We conducted a comprehensive review of the epidemiologic literature and hypothesized mechanisms pertaining to EMF exposure and the risk of breast cancer, in order to assess whether or not there was evidence to suggest a link between EMF and breast cancer., Results: Some occupational epidemiological studies have demonstrated an increased incidence of breast cancer among mainly male electrical workers. It has been difficult to study women, as few are employed in these types of occupations. In all, there have been eleven occupational studies related to breast cancer in women, and statistically significant risk ratios have been observed: 1.98 for pre-menopausal women in occupations with high EMF exposure in one study, 2.17 in all women who worked as telephone installers, repairers, and line workers in another study, and 1.65 for system analysts/ programmers, 1.40 for telegraph and radio operators, and 1.27 for telephone operators in a third study. However, six of the studies did not find any significant effects and two found effects only in subgroups. The results of the eight studies of residential exposure and four electric blanket studies have been inconsistent, with most not demonstrating any significant association. However, this might be attributed, at least to some extent, to difficulties in assessing residential exposure in these studies, as well as other methodological considerations., Conclusions: The biologic plausibility of an association between EMF and breast cancer, coupled with suggestive data from occupational studies and unexplained high incidence rates of breast cancer, suggests that further investigation of this possible association is warranted.

The accurate and valid measurement of personal exposure to magnetic fields poses a major challenge for epidemiologic studies. When considering the various methods to assess exposure, it is unclear which measures are most relevant for studies of human disease, if any. Given these uncertainties, the Electromagnetic Fields and Breast Cancer on Long Island Study (EBCLIS) undertook a pilot study to develop the data collection protocol for a case-control study of breast cancer and magnetic fields. The pilot study used and compared various methods to assess residential exposures to magnetic fields, and related these measures to personal exposures. It included 31 women without breast cancer (mean age, 63+/-7 yr) who lived in their present homes for at least 15 yr. The pilot study consisted of an in-home interview, spot and 24-h magnetic field waveforms and broadband recordings, ground currents, wire coding, and personal 24-h broadband measurements. From the regression analyses, the model that best predicted personal magnetic field exposures included 24-h measurements in the bedroom and in the most lived-in room; as well as ground current test loads taken at the center of this most lived in room (r(2)=86%). The addition of other variables in this regression model yielded only small and nonsignificant increases in r(2). As a direct result of this pilot, EBCLIS will include ground current measurements in its protocol, which have not previously been collected as part of an epidemiologic study. Ground currents may be important because they may be richer in 180 Hz components than are the other currents in a power system. EBCLIS will have the opportunity to examine the ground-current hypothesis in the context of female breast cancer., (Copyright 1999 Wiley-Liss, Inc.)

Purpose: To describe the prevalence of refractive errors in a black adult population., Methods: The Barbados Eye Study, a population-based study, included 4709 Barbados-born citizens, or 84% of a random sample, 40 to 84 years of age. Myopia and hyperopia were defined as a spherical equivalent <-0.5 diopters and >+0.5 diopters, respectively, based on automated refraction. Analyses included 4036 black participants without history of cataract surgery. Associations with myopia and hyperopia were evaluated in logistic regression analyses., Results: The prevalence of myopia was 21.9% and was higher in men (25.0%) than in women (19.5%). The prevalence of hyperopia was 46.9% and was higher in women (51.8%) than in men (40.5%). The prevalence of myopia decreased from 17% in persons 40 to 49 years of age to 11% in those 50 to 59 years of age, but increased after 60 years of age. The prevalence of hyperopia increased from 29% at 40 to 49 years of age to 65% at 50 to 59 years of age, and tended to decline thereafter. A higher prevalence of myopia was positively associated (P < 0.05) with lifetime occupations requiring nearwork, nuclear opacities, posterior subcapsular opacities, glaucoma, and ocular hypertension. Factors associated with hyperopia were the same as for myopia, except for occupation, and in the opposite direction., Conclusions: High prevalences of myopia and hyperopia were found in this large black adult population. The prevalence of myopia (hyperopia) increased (decreased) after 60 years of age, which is inconsistent with data from other studies. The high prevalence of age-related cataract, glaucoma, and other eye conditions in the Barbados Eye Study population may contribute to the findings.