Tyler Hyungtaek Rim1, Ryo Kawasaki2, Yih-Chung Tham1, Se Woong Kang3, Paisan Ruamviboonsuk4, Mukharram M Bikbov5, Masahiro Miyake6, Jie Hao7, Astrid Fletcher8, Mariko Sasaki9, Vinay Nangia10, Charumathi Sabanayagam1, Marco Yu11, Kohta Fujiwara12, Raba Thapa13, Ian Y Wong14, Takamasa Kayama15, Shih-Jen Chen16, Tung-Mei Kuang16, Hidetoshi Yamashita15, Periasamy Sundaresan17, Jonathan C Chan18, G H M B van Rens19, Koh-Hei Sonoda20, Ya Xing Wang7, Songhomitra Panda-Jonas21, Sei Harada22, Ramasamy Kim23, Suganeswari Ganesan24, Rajiv Raman24, Kenji Yamashiro25, Timur R Gilmanshin5, Watanee Jenchitr26, Kyu Hyung Park27, Chui Ming Gemmy Cheung1, Tien Yin Wong1, Ningli Wang7, Jost B Jonas28, Usha Chakravarthy29, Ching-Yu Cheng30, Yasuo Yanagi31. 1. Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore. 2. Department of Ophthalmology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan; Ganka Ekigaku Network, Osaka, Japan. 3. Department of Ophthalmology of Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. 4. Department of Ophthalmology, Rajavithi Hospital, Bangkok, Thailand. 5. Ufa Eye Research Institute, Ufa, Russia. 6. Ganka Ekigaku Network, Osaka, Japan; Department of Ophthalmology, Kyoto University Graduate School of Medicine, Kyoto, Japan. 7. Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, Beijing, China. 8. London School of Hygiene & Tropical Medicine, London, United Kingdom. 9. Ganka Ekigaku Network, Osaka, Japan; Department of Ophthalmology, Keio University school of medicine, Tokyo, Japan. 10. Suraj Eye Institute, Nagpur, India. 11. Singapore Eye Research Institute, Singapore National Eye Centre, Singapore. 12. Ganka Ekigaku Network, Osaka, Japan; Department of Epidemiology and Public Health, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. 13. Tilganga Institute of Ophthalmology, Kathmandu, Nepal. 14. University of Hong Kong and Hong Kong Sanatorium and Hospital, Hong Kong. 15. Yamagata University Faculty of Medicine, Yamagata, Japan. 16. Department of Ophthalmology, Taipei Veterans General Hospital, School of Medicine, National Yang-Ming University, Taipei, Taiwan. 17. Department of Molecular Genetics, Aravind Medical Research Foundation, Madurai, Tamil Nadu, India. 18. Department of Ophthalmology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong. 19. Department of Ophthalmology, Amsterdam University Medical Center, Vrije University Amsterdam, Amsterdam, The Netherlands. 20. Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. 21. Augenpraxis Jonas, Heidelberg, Germany. 22. Department of Preventive Medicine and Public Health, Keio University School of Medicine, Tokyo, Japan. 23. Department of Ophthalmology, Aravind Eye Hospital, Madurai, Tamil Nadu, India. 24. Medical Research Foundation, Sankara Nethralaya, Chennai, India. 25. Department of Ophthalmology, Kyoto University Graduate School of Medicine, Kyoto, Japan; Department of Ophthalmology, Otsu Red Cross Hospital, Otsu, Japan. 26. Rangsit Eye Center and Faculty of Optometry, Rangsit University, Bangkok, Thailand. 27. Department of Ophthalmology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seoul, Korea. 28. Department of Ophthalmology, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany. 29. Queen's University of Belfast, Belfast, Northern Ireland. 30. Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Ophthalmology & Visual Sciences Academic Clinical Program (Eye ACP), Duke-NUS Medical School, Singapore. Electronic address: chingyu.cheng@duke-nus.edu.sg. 31. Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Ganka Ekigaku Network, Osaka, Japan; Department of Ophthalmology, Asahikawa Medical University, Hokkaido, Japan. Electronic address: yasuo.yanagi.asahikawa@gmail.com.
Abstract
PURPOSE: Although there have been many population-based studies of age-related macular degeneration (AMD), only limited information is available in Asia on the epidemiology of geographic atrophy (GA). We aimed to determine the prevalence and patterns of GA through an analysis of multiple studies conducted within the Asian Eye Epidemiology Consortium (AEEC). DESIGN: Cross-sectional meta-analyses. PARTICIPANTS: A total of 97 213 individuals aged 40 years and older. METHODS: Data from 22 population-based studies from countries belonging to the AEEC were included. In all studies, AMD was defined on the basis of standardized grading systems. Geographic atrophy was defined as an area of pallor in the fundus with visibility of the underlying choroidal blood vessels and sharply defined borders. Random-effects meta-analysis was performed to estimate overall and age-, gender-, and region-specific pooled prevalence of GA. MAIN OUTCOME MEASURES: Prevalence of GA per 1000 persons. RESULTS: The mean age was 60.8 ± 10.0 years, and 42 673 (43.9%) were male. Overall, a total of 223 individuals (0.2%) had GA. The pooled overall prevalence of GA was 1.57 per 1000 persons (95% confidence interval [CI], 1.04-2.10), which was 3 times less than that of neovascular AMD of 5.20 per 1000 persons (95% CI, 3.97-6.43). Compared with those aged 50 to 59 years, the prevalence of GA increased from 0.34 per 1000 persons (95% CI, 0.07-0.62) to 2.90 per 1000 persons (95% CI, 1.55-4.25) in those aged ≥70 years. The GA prevalence per 1000 persons was similar between urban (2.22; 95% CI, 1.22-3.23) and rural residents (1.33; 95% CI, 0.70-1.96). Geographic atrophy was more prevalent in South Asia (based on studies from India and Nepal, 3.82 per 1000 persons; 95% CI, 1.72-5.93) compared with East Asia (based on studies from China, Korea, Hong Kong, Taiwan, and Japan, and the Singapore Chinese Eye Study, 0.76 per 1000 persons; 95% CI, 0.31-1.22, P = 0.005). CONCLUSIONS: Geographic atrophy is uncommon in Asian populations compared with those of European ancestry. Even within Asia, geographic differences in GA prevalence were seen. The findings of this meta-analysis suggest that better dissection of risk factors in the Asian population for GA may provide insights into the biological pathways that drive these late-stage manifestations, thus suggesting better targets for prevention.
PURPOSE: Although there have been many population-based studies of age-related macular degeneration (AMD), only limited information is available in Asia on the epidemiology of geographic atrophy (GA). We aimed to determine the prevalence and patterns of GA through an analysis of multiple studies conducted within the Asian Eye Epidemiology Consortium (AEEC). DESIGN: Cross-sectional meta-analyses. PARTICIPANTS: A total of 97 213 individuals aged 40 years and older. METHODS: Data from 22 population-based studies from countries belonging to the AEEC were included. In all studies, AMD was defined on the basis of standardized grading systems. Geographic atrophy was defined as an area of pallor in the fundus with visibility of the underlying choroidal blood vessels and sharply defined borders. Random-effects meta-analysis was performed to estimate overall and age-, gender-, and region-specific pooled prevalence of GA. MAIN OUTCOME MEASURES: Prevalence of GA per 1000 persons. RESULTS: The mean age was 60.8 ± 10.0 years, and 42 673 (43.9%) were male. Overall, a total of 223 individuals (0.2%) had GA. The pooled overall prevalence of GA was 1.57 per 1000 persons (95% confidence interval [CI], 1.04-2.10), which was 3 times less than that of neovascular AMD of 5.20 per 1000 persons (95% CI, 3.97-6.43). Compared with those aged 50 to 59 years, the prevalence of GA increased from 0.34 per 1000 persons (95% CI, 0.07-0.62) to 2.90 per 1000 persons (95% CI, 1.55-4.25) in those aged ≥70 years. The GA prevalence per 1000 persons was similar between urban (2.22; 95% CI, 1.22-3.23) and rural residents (1.33; 95% CI, 0.70-1.96). Geographic atrophy was more prevalent in South Asia (based on studies from India and Nepal, 3.82 per 1000 persons; 95% CI, 1.72-5.93) compared with East Asia (based on studies from China, Korea, Hong Kong, Taiwan, and Japan, and the Singapore Chinese Eye Study, 0.76 per 1000 persons; 95% CI, 0.31-1.22, P = 0.005). CONCLUSIONS: Geographic atrophy is uncommon in Asian populations compared with those of European ancestry. Even within Asia, geographic differences in GA prevalence were seen. The findings of this meta-analysis suggest that better dissection of risk factors in the Asian population for GA may provide insights into the biological pathways that drive these late-stage manifestations, thus suggesting better targets for prevention.