RESUMO
OBJECTIVE: To evaluate the association between cataract and mortality in a black population by type of opacity, which has not been documented previously. DESIGN: Population-based cohort study. PARTICIPANTS: The Barbados Incidence Study of Eye Diseases reexamined the Barbados Eye Study cohort, identified through a simple random sample of predominantly black Barbadian-born citizens, aged 40 to 84 years. Of those eligible, 85% (3427 participants) had a 4-year follow-up visit. METHODS: Baseline and follow-up visits included an interview, blood pressure and other measurements, and a detailed ophthalmologic examination with slit-lamp lens gradings (Lens Opacities Classification System [LOCS] II protocol). Mortality at follow-up was verified from Ministry of Health records. MAIN OUTCOME MEASURES: Lens opacities were defined by a LOCS II score of 2 or more. Opacity types were classified in two ways: (1) single (cortical-only, nuclear-only, and posterior subcapsular-only) and mixed opacities; and (2) any cortical, any nuclear, or any posterior subcapsular opacities. Information on dates and causes of death was obtained from death certificates. RESULTS: Cardiovascular disease was the principal cause of death in black participants (3.6%), followed by malignant neoplasms (1.4%). The cumulative 4-year mortality varied with lens types, increasing from 3.2% for those without cataract to 6.0% for cortical-only, 8.8% for nuclear-only, and 20.9% for mixed opacities. Persons with mixed opacities had a 1.6-fold increase in mortality, while controlling for other factors (age, male gender, diabetes, hypertension, obesity, cigarette smoking, cardiovascular disease, and family history of diabetes) in Cox proportional-hazards regression analyses. Persons with any nuclear opacities also had increased mortality (death rate ratio, 1.5). The death rate ratios increased with age, but peaked at age 60 to 69 years. Coexisting diabetes further increased mortality: people with mixed opacities and diabetes had a 2.7-fold increased risk of death. A trend toward increased mortality from neoplasms was observed for individuals with mixed opacities or with any nuclear opacities. CONCLUSIONS: Participants with mixed opacities or any nuclear opacities had increased 4-year mortality rates, with diabetes acting as an effect modifier. This study is the first to identify a relationship between type of cataract and mortality in an African-descent population.
Assuntos
População Negra , Catarata/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Barbados/epidemiologia , Catarata/classificação , Catarata/etnologia , Causas de Morte , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Modelos de Riscos ProporcionaisRESUMO
OBJECTIVE: Age related cataract is the major cause of visual impairment globally, and is more prevalent in black than white populations. Several studies have shown associations between cataract and mortality, and this report aimed to examine whether lens opacities were associated with mortality in an Afro-Caribbean population. DESIGN AND METHODS: The Barbados Incidence Study of Eye Disease (BISED) re-examined the Barbados Eye Study (BES) cohort, which was based on a simple random sample of Barbadian-born citizens, age 40 to 84 years. Eighty-five percent of those eligible (3,427 participants) has a 4-year follow-up visit. Both visits included an interview, anthropometric measurements, and a detailed ophthalmologic examination, including lens grading with the LOCS II method. Mortality was verified from records held at the Ministry of Health. RESULTS: Cardiovascular disease was the principal cause of death (3.7 percent), followed by malignant neoplasms (1.4 percent). Cumulative 4-year mortality increased from 3.1 percent among those without cataract to 6.0 percent, 8.9 percent and 19.6 percent for cortical-only, nuclear-only and mixed cataract, respectively. An independent association was demonstrated between mixed opacities and 4-year mortality (death rate ratio: 1.6). Co-existing diabetes acted as an effect modifier, increasing mortality in those with mixed lens opacities. The presence of any nuclear cataract (death rate ratio 1.5) was also associated with an increase risk of death. CONCLUSION: This study is the first to confirm an association between cataract and mortality in a population of African descent.(AU)