Causes and prevalence of visual impairment among adults in the United States.

OBJECTIVES: To estimate the cause-specific prevalence and distribution of blindness and low vision in the United States by age, race/ethnicity, and gender, and to estimate the change in these prevalence figures over the next 20 years. METHODS: Summary prevalence estimates of blindness (both according to the US definition of < or =6/60 [< or =20/200] best-corrected visual acuity in the better-seeing eye and the World Health Organization standard of < 6/120 [< 20/400]) and low vision (< 6/12 [< 20/40] best-corrected vision in the better-seeing eye) were prepared separately for black, Hispanic, and white persons in 5-year age intervals starting at 40 years. The estimated prevalences were based on recent population-based studies in the United States, Australia, and Europe. These estimates were applied to 2000 US Census data, and to projected US population figures for 2020, to estimate the number of Americans with visual impairment. Cause-specific prevalences of blindness and low vision were also estimated for the different racial/ethnic groups. RESULTS: Based on demographics from the 2000 US Census, an estimated 937 000 (0.78%) Americans older than 40 years were blind (US definition). An additional 2.4 million Americans (1.98%) had low vision. The leading cause of blindness among white persons was age-related macular degeneration (54.4% of the cases), while among black persons, cataract and glaucoma accounted for more than 60% of blindness. Cataract was the leading cause of low vision, responsible for approximately 50% of bilateral vision worse than 6/12 (20/40) among white, black, and Hispanic persons. The number of blind persons in the US is projected to increase by 70% to 1.6 million by 2020, with a similar rise projected for low vision. CONCLUSIONS: Blindness or low vision affects approximately 1 in 28 Americans older than 40 years. The specific causes of visual impairment, and especially blindness, vary greatly by race/ethnicity. The prevalence of visual disabilities will increase markedly during the next 20 years, owing largely to the aging of the US population.

Prevalence of cataract and pseudophakia/aphakia among adults in the United States.

OBJECTIVES:

To determine the prevalence of cataract and pseudophakia/aphakia in the United States and to project the expected change in these prevalence figures by 2020.

METHODS:

Summary prevalence estimates of cataract and of pseudophakia/aphakia were prepared separately for black, white, and Hispanic persons (for whom only cataract surgery data were available) in 5-year age intervals starting at 40 years for women and men. The estimates were based on a standardized definition of various types of cataract: cortical, greater than 25% of the lens involved; posterior subcapsular, present according to the grading system used in each study; and nuclear, greater than or equal to the penultimate grade in the system used. Data were collected from major population-based studies in the United States, and, where appropriate, Australia, Barbados, and Western Europe. The age-, gender-, and race/ethnicity-specific rates were applied to 2000 US Census data, and projected population figures for 2020, to obtain overall estimates.

RESULTS:

An estimated 20.5 million (17.2%) Americans older than 40 years have cataract in either eye, and 6.1 million (5.1%) have pseudophakia/aphakia. Women have a significantly (odds ratio = 1.37; 95% confidence interval, 1.26-1.50) higher age-adjusted prevalence of cataract than men in the United States. The total number of persons who have cataract is estimated to rise to 30.1 million by 2020; and for those who are expected to have pseudophakia/aphakia, to 9.5 million.

CONCLUSION:

The number of Americans affected by cataract and undergoing cataract surgery will dramatically increase over the next 20 years as the US population ages.

A Community Driven Approach to Reconstruction Management

Without human beings, and human activities, hazards can strike but disasters cannot occur, they are not just natural phenomena but a social event (Van Der Zon, 2005). The rapid demand for reconstruction after disastrous events can result in the impacts of projects not being carefully considered from the outset and the opportunity to improve long-term physical and social community structures being neglected. The events that struck Banda Aceh in 2004 have been described as
a story of ‘two tsunamis’, the first being the natural hazard that struck and the second being the destruction of social structures that occurred as a result of unplanned, unregulated and uncoordinated response (Syukrizal et al, 2009). Measures must be in place to ensure that, while aiming to meet reconstruction
needs as rapidly as possible, the risk of re-occurring disaster impacts are reduced through both the physical structures and the capacity of the community who inhabit them. The paper explores issues facing reconstruction in a post-disaster scenario, drawing on the connections between physical and social reconstruction in order to address long term recovery solutions. It draws on a study of relevant literature and a six week pilot study spent in Haiti exploring the progress of recovery in the Haitian capital and the limitations still restricting reconstruction efforts. The study highlights the need for recovery management strategies that recognise the link between social and physical reconstruction and the significance of community based initiatives that see local residents driving recovery in terms of debris handling and rebuilding. It demonstrates how a community driven approach to physical reconstruction could also address the social impacts of events that, in the case of places such as Haiti, are still dramatically restricting recovery efforts.