Age-related macular degeneration: cost-of-illness issues

Macular degeneration refers to the breakdown of cells in the centre of the retina. Some degeneration is an inevitable consequence of the aging process; however, when this is associated with loss of sight in the central part of the field of vision an underlying pathology is considered present. Among those aged 55 years, the prevalence of the disease in the US was estimated at 1% rising to approximately 15% among those aged 80 years. Other studies estimate the prevalence of the disease to be higher and to be increasing. The main effect of the disease is to reduce the ability of the individual to engage in everyday activities that require clear central vision. It may also be associated with elevated risks of depression and increased levels of dependency. Currently there is no effective treatment for the majority of patients. For a minority (< 10%) laser photocoagulation therapy may be effective in reducing the risk of severe vision loss. Another treatment, photodynamic therapy, is in development and many others are at an experimental stage. This review sought to establish current knowledge on the cost of illness associated with age-related macular degeneration (ARMD). A search of the literature, together with direct communication with researchers in related fields and patient support/advocacy groups, was undertaken to ascertain current knowledge on the cost of illness of ARMD. While literature on the disease is extensive and literature on treatments is emerging, no substantive information on direct or indirect costs was found although evidence that loss of earnings may occur is beginning to emerge. Some information does exist on cost of illness in diabetic retinopathy, a disease with similarities to ARMD, though even for this disease gaps in knowledge are apparent and wide variations exhibited. Given current knowledge, it is not possible to report on the cost of illness for ARMD with confidence. The lack of information on the cost of illness in ARMD presents difficulties for researchers and policy makers in assessing the cost effectiveness of the existing treatment, as well as new treatments as they become available. Given developments in treatments and the increasing prevalence of the disease, it is important that cost-of-illness information is gathered for ARMD.