Declined incidence of patients treated for vision-threatening diabetic retinopathy in South Korea: a 12-year nationwide population-based study

Purpose To determine the age- and sex-specific annual incidence rates of patients treated for VTDR and the factors associated with increased treatment rates in patients with type 2 diabetes mellitus (T2DM) in South Korea. Methods This was a nationwide, retrospective, 12-year, population-based study. Patients aged over 30 years who were diagnosed with T2DM between 2006 and 2017 were included in this study. We evaluated the national health claims data acquired from the Korean National Health Insurance Service database. Main outcome measures were the annual incidence rates of patients treated for VTDR and the associated risk factors. Results The age-adjusted annual incidence rate of patients treated for VTDR significantly decreased from 10.05 per 1000 T2DM patients in 2006 to 6.11 in 2017 ( β = − 0.3192, P < 0.0001). The sex-adjusted annual incidence rate also significantly decreased in both men ( β = − 0.2861, P < 0.0001) and women ( β = − 0.3666, P < 0.0001). Cox hazard analysis showed that factors such as insulin use, young age, chronic kidney disease and male sex were significantly associated with increased rate of treatments for VTDR. In addition, the risk was lower for rural than for metropolitan residents. Conclusions Despite the increase in the number of T2DM patients in South Korea, the incidence rate of patients treated for VTDR decreases with early diagnosis and appropriate treatment. Therefore, it is important to detect and manage high-risk groups early to prevent visual impairment due to VTDR.