Age-Related Macular Degeneration: The Leading Cause of Vision Loss in Aging Adults
Age-related macular degeneration (AMD) is a progressive eye disorder and one of the leading causes of irreversible vision loss among individuals aged 50 and above. The epidemiology of Age-Related Macular Degeneration provides critical insights into its prevalence, risk factors, demographic variations, and the growing healthcare burden associated with this condition.
Globally, AMD affects an estimated 200 million people, a number projected to rise to nearly 300 million by 2040 due to the aging population. The disease primarily affects the central part of the retina (the macula), responsible for sharp and detailed vision. It occurs in two major forms: dry (non-neovascular) AMD, which is more common and progresses slowly, and wet (neovascular) AMD, which is less common but more severe and responsible for the majority of AMD-related blindness.
Epidemiological studies indicate that AMD is more prevalent in populations of European descent, with lower rates reported in African and Asian populations. In developed countries, AMD is the leading cause of visual impairment in the elderly. For instance, in the United States, approximately 11 million individuals are currently affected by some form of AMD.
Age is the most significant risk factor for AMD, with incidence rates increasing sharply after the age of 60. Other major risk factors identified in epidemiological research include smoking, family history, hypertension, obesity, and prolonged exposure to ultraviolet (UV) light. Genetic predispositions, particularly variants in the CFH and ARMS2 genes, also play a critical role in susceptibility to AMD.
The study of AMD epidemiology also sheds light on disparities in disease outcomes and access to care. In low- and middle-income countries, underdiagnosis and lack of access to treatment such as anti-VEGF (vascular endothelial growth factor) therapies contribute to higher rates of vision loss. Conversely, early detection and regular monitoring in high-income countries have led to better management and improved quality of life for patients.
Moreover, population-based cohort studies such as the Beaver Dam Eye Study, the Rotterdam Study, and the Blue Mountains Eye Study have provided longitudinal data that help understand AMD progression and inform public health strategies.