Severity of Visual Field Loss at First Presentation to Glaucoma Clinics in England and Tanzania

Purpose: To compare severity of visual field (VF) loss at first presentation in glaucoma clinics in England and Tanzania. Methods: Large archives of VF records from automated perimetry were used to retrospectively examine vision loss at first presentation in glaucoma clinics in Tanzania (N = 1,502) and England (N = 9,264). Mean deviation (MD) of the worse eye at the first hospital visit was used as an estimate of detectable VF loss severity. Results: In Tanzania, 44.7% {CI95%: 42.2, 47.2} of patients presented with severe VF loss (< −20 dB), versus 4.6% {4.1, 5.0} in England. If we consider late presentation to also include cases of advanced loss (-12.01 dB to -20 dB), then the proportion of patients presenting late was 58.1% {55.6, 60.6} and 14.0% {13.3, 14.7}, respectively. The proportion of late presentations was greater in Tanzania at all ages, but the difference was particularly pronounced among working-age adults, with 50.3% {46.9, 53.7} of 18–65-year-olds presenting with advanced or severe VF loss, versus 10.2% {9.3, 11.3} in England. In both countries, men were more likely to present late than women. Conclusions: Late presentation of glaucoma is a problem in England, and an even greater challenge in Tanzania. Possible solutions are discussed, including increased community eye-care, and a more proactive approach to case finding through the use of disruptive new technologies, such as low-cost, portable diagnostic aids

Number of People Blind or Visually Impaired by Glaucoma Worldwide and in World Regions 1990 – 2010: A Meta-Analysis

Objective: To assess the number of individuals visually impaired or blind due to glaucoma and to examine regional differences and temporal changes in this parameter for the period from 1990 to 2012. Methods: As part of the Global Burden of Diseases (GBD) Study 2010, we performed a systematic literature review for the period from 1980 to 2012. We primarily identified 14,908 relevant manuscripts, out of which 243 high-quality, population-based studies remained after review by an expert panel that involved application of selection criteria that dwelt on population representativeness and clarity of visual acuity methods used. Sixty-six specified the proportion attributable to glaucoma. The software tool DisMod-MR (Disease Modeling–Metaregression) of the GBD was used to calculate fraction of vision impairment due to glaucoma. Results: In 2010, 2.1 million (95% Uncertainty Interval (UI):1.9,2.6) people were blind, and 4.2 (95% UI:3.7,5.8) million were visually impaired due to glaucoma. Glaucoma caused worldwide 6.6% (95% UI:5.9,7.9) of all blindness in 2010 and 2.2% (95% UI:2.0,2.8) of all moderate and severe visual impairment (MSVI). These figures were lower in regions with younger populations (10%). From 1990 to 2010, the number of blind or visually impaired due to glaucoma increased by 0.8 million (95%UI:0.7, 1.1) or 62% and by 2.3 million (95%UI:2.1,3.5) or 83%, respectively. Percentage of global blindness caused by glaucoma increased between 1990 and 2010 from 4.4% (4.0,5.1) to 6.6%. Age-standardized prevalence of glaucoma related blindness and MSVI did not differ markedly between world regions nor between women. Significance: By 2010, one out of 15 blind people was blind due to glaucoma, and one of 45 visually impaired people was visually impaired, highlighting the increasing global burden of glaucoma

Prevalence and risk factors of primary open-angle glaucoma in a city of Eastern China: a population-based study in Pudong New District, Shanghai

BACKGROUND: The aim of the present study was to investigate the prevalence and characteristics of primary open-angle glaucoma among the urban population of Pudong New District, Shanghai. METHODS: Three residents’ committees were randomly selected from Pudong New District, and residents aged 50 and older were screened for primary open-angle glaucoma (POAG) from March to April 2011. In remote screening, the tests on visual acuity, refraction, intraocular pressure (IOP), and the photographs of anterior segment and fundus were used to identify POAG suspect. The suspected subjects were then reexamined with the tests on IOP, gonioscopy, Humphrey visual field test, and retinal nerve fiber layer (RNFL) thickness by optical coherence tomography (OCT). POAG was diagnosed according to the criteria defined by International Society for Geographic and Epidemiological Ophthalmology (ISGEO). Finally, POAG risk factors were evaluated using logistic regression analysis. RESULTS: A total of 2528 citizens out of 3,146 eligible residents (80.36 %) participated in this study. Among the citizens, 72 were diagnosed to have POAG, giving the crude prevalence rate of 2.85 % (95 % CI:2.20 %–3.50 %) in general and age- and gender-adjusted prevalence rate of 2.8 % (95 % CI: 2.78 %–2.83 %). Among the 72 POAG patients, only 22 cases had IOP exceeding 21 mmHg while other 50 cases had IOP of 21 mmHg or less; nine cases had one eye blind (12.5 %). Intriguingly, only eight cases (11.11 %) had been diagnosed with POAG before this screening. CONCLUSIONS: More efforts are required for early screening and education on POAG in communities, especially in a POAG high-risk population