Nine-Year Incidence of Age-Related Macular Degeneration in the Barbados Eye Studies
Received 18 March 2005; accepted 10 August 2005. published online 11 November 2005.
Objective
To provide 9-year incidence estimates of age-related macular degeneration (AMD) in a population of African descent.
Design
Population-based cohort study.
Participants
Two thousand seven hundred ninety-three participants (81% of eligible) after 9 years’ follow-up.
Main Outcome Measures
Nine-year incidence of AMD-related features, based on fundus photographic gradings and/or clinical examinations.
Results
The overall incidence rate of early AMD was 12.6% (95% confidence interval [CI], 11.0%–14.1%), and that of late AMD was 0.7% (95% CI, 0.4%–1.1%). Both increased with age (P<0.05). For early AMD, incidence ranged from 10.7% at 40 to 49 years of age to 16.8% at ≥70 years. For late AMD, incidence increased from 0.1% to 2.3% in the same age groups. Late AMD was more likely to develop in eyes with pigment changes (risk ratio [RR], 5.8; 95% CI, 2.0–16.8) and retinal pigment epithelial atrophy (RR, 5.4; 95% CI, 1.9–15.8) at baseline. Crude RRs indicated significant associations of late AMD to elevated systolic blood pressure and diabetes history, but only the diabetes relationship was suggested after adjusting for age, with borderline statistical significance (age-adjusted RR, 2.7; P = 0.054).
Conclusions
Nine-year data on natural history indicate that early AMD is common in this population of African origin, although late AMD is infrequent. These long-term observations provide further evidence for the lower AMD risk in black populations compared with white populations.
1Department of Preventive Medicine, Stony Brook University, Stony Brook, New York.
3Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
4Chronic Disease Research Center, School of Clinical Medicine and Research, University of the West Indies, Barbados.
Correspondence and reprint requests to M. Cristina Leske, MD, MPH, Department of Preventive Medicine, Stony Brook University, HSC L3 086, Stony Brook, NY 11794-8036.
Manuscript no. 2005-242.
Supported by the National Eye Institute, Bethesda, Maryland (grant nos.: EY07625, EY07617).
The authors have no conflicts of interest with regard to the article.
ABSTRACT