[Future need of eye care for patients with diabetes mellitus, costs and effectiveness].
OBJECTIVE: To determine how much vision loss caused by diabetic retinopathy can be prevented in the Netherlands until 2020, and what resources will be needed to do so. DESIGN: Computer simulation study. METHODS: The population forecasts of the Dutch Central Bureau of Statistics constituted the starting points. The literature provided data on the disease progression and the effectiveness of screening and treatment. A new continuous computer simulation assessed one scenario without eye care and four scenarios with different screening frequencies. Effects were measured in sight gain, costs were based on official charges, benefits included savings on disability facilities and reductions in production losses. RESULTS: The number of diabetic patients was estimated to increase form 287,000 in 1993 to 406,000 in 2020. Compared with a setting without ophthalmic care, full compliance with official screening guidelines would reduce the prevalence of blindness in 2020 by 45% among type I patients, and by 20% among type II patients. Financial benefits would exceed costs for type I, but not for type II diabetes. While the intensity of eye care would rise, the number of eye examinations would increase approximately in the same proportion, but the number of laser treatments would increase at a much slower rate. 30% more ophthalmologists were estimated to be required in 2020. CONCLUSIONS: The sharp increase in the number of diabetic patients plus the proven effectiveness of photocoagulation will inevitably cause a major rise in the need for ophthalmic care.