Many large, population-based, cross-sectional studies have documented the increase in prevalence of eye disease and visual impairment with increasing age, particularly in persons over the age of 75 years. U.S. population estimates indicate that more than 26 million people over the age of 40 years are affected with some type of visual disorder and that more than 4 million individuals in the U.S. aged 55 years or older are currently experiencing severe vision loss.
Estimates of the prevalence of visual impairment per 1000 persons in the United States demonstrate the significant increase in vision problems with age. A 2001 study estimated that 14% of persons aged 70 to 74 years have serious difficulty seeing, even with their spectacle correction, and this increases to 32% among persons aged 85 years or older. Centers for Disease Control and Prevention (CDC) and the National Centers for Health Statistics (NCHS) estimate the prevalence of severe visual impairment among persons 70 to 74 years of age at about 1% of the elderly population, but by age 85 years, nearly 2.5% of persons are severely visually impaired. After age 85 years, one in four older people cannot read a newspaper even with best-corrected vision.
Age-related visual impairment is not only challenging to the person in whom it develops, but also affects society as a whole. Medicare beneficiaries with coded diagnoses of vision loss have been shown to incur an additional $2.14 billion in 2003 in noneye-related medical costs, incurring significantly higher costs than those with normal vision. Additional eye-related costs per patient yearly are approximately $345 for those with moderate vision loss, $407 for those with severe vision loss, and $237 for those who are blind. Additional noneye-related costs per patient yearly are $2193, $3301, and $4443, respectively. Prevent Blindness America, a national volunteer eye health and safety organization, puts the medical loss for visual impairment at $5.48 billion for persons 40 years and older. Their number includes increased medical expenditures, as well as increased informal care days. They define informal care as unpaid care provided by people not living with the older person, and valued it according to minimum wage dollars. Health utility (distress, pain, depression, lack of mobility, social limitations) was converted into quality-adjusted life years and the total lost value for this factor was $10.5 billion. Thus, preventing vision loss among older persons is not only a medical imperative, but also an economic one.
Vision loss is reason enough for a decline in function among older persons, but vision loss has also been associated with cognitive decline, heart disease, arthritis, hypertension, falls and hip fracture, depression, reduced overall quality of life and mortality. Older visually impaired persons are twice as likely to have difficulty walking as do sighted peers, three times more likely to have difficulty getting outside, more than twice as likely to have difficulty getting in and out of a bed/chair, and three times more likely to have difficulty ...