Purpose: To identify the medical costs for diabetic patients with stable or progressive retinopathy in Taiwan.
Participants: Four-thousand, nine-hundred eighty-eight medication-using diabetic subjects age ≥ 40 years or older under National Health Insurance Program coverage  in 2000.
Methods: Our study is a retrospective, longitudinal, cohort study. In our study population there are 4,988 medication-using diabetic subjects age ≥ 40 years or older under National Health Insurance Program coverage in 2000. Search of the National Health Insurance database identifying patients diagnosed with diabetic retinopathy, based on International Classification of Diseases 9, Clinical Modification codes with review of electronic inpatient, outpatient, and pharmacy records. Subjects were divided into 2 groups, stable or progressive.
Results: During the 5-year follow-up, 79.8% of the 4,988 diabetic subjects were classified as stable and 20.2% classified as progressive. Average costs in New Taiwan dollars (NT$) in the stable category increased NT$1,543, (US $48) from NT$62,218 (US $1921) to NT$63,761 (US $1969) (p=0.594), whereas costs for those progressing from normal-to-non-proliferative diabetic retinopathy (NPDR) or proliferative diabetic retinopathy (PDR) increased NT$57,020 (US $1760), from NT$50,712 (US $1566) to NT$107,732 (US $3326) (p<0.001). The PDR-to-PDR category had the highest average costs at NT$117,630 (US $3632) in 2000, but the NPDR-to-PDR category experienced the greatest increase in costs at NT$112,779 (US $3482), from NT$88,182 (US $2723) to NT$200,961(US $6204) (p=0.042).
Conclusion: This nationwide, large-scale, and longitudinal study provides evidence that strategies aimed at the prevention and mitigation of diabetes-related ophthalmic complications can reduce healthcare costs over the long term.