Healthcare Utilization and Discrepancies by Income Level Among Patients With Newly Diagnosed Type 2 Diabetes in Korea: An Analysis of National Health Insurance Sample Cohort Data

Objectives: The use of qualitative healthcare services or its discrepancy between different income levels of the type 2 diabetes (T2D) patients has seldom been studied concurrently. The present study is unique that regarding T2D patients of early stages of diagnosis. Aimed to assess the utilization of qualitative healthcare services and influence of income levels on the inequality of care among newly diagnosed patients with T2D. Methods: A retrospective cohort study of 7590 patients was conducted by the National Health Insurance Service National Sample Cohort 2.0 from 2002 to 2015. Insured employee in 2013 with no history of T2D between 2002 and 2012 were included. The standard of diabetes care includes hemoglobin A1c (HbAlc; 4 times/y), eyes (once/y) and lipid abnormalities (once/y). Multivariate logistic regression analysis was performed to examine the difference between income levels and inequality of care. Results: From years 1 to 3, rates of appropriate screening fell from 16.9% to 14.1% (HbA1c), 15.8% to 14.5% (eye), and 59.2% to 33.2% (lipid abnormalities). Relative to income class 5 (the highest-income group), HbA1 screening was significantly less common in class 2 (year 2: odds ratio [OR], 0.78; 95% confidence interval [CI], 0.61 to 0.99; year 3: OR, 0.79; 95% CI, 0.69 to 0.91). In year 1, lipid screening was less common in class 1 (OR, 0.84; 95% CI, 0.73 to 0.98) than in class 5, a trend that continued in year 2. Eye screening rates were consistently lower in class 1 than in class 5 (year 1: OR, 0.73; 95% CI, 0.60 to 0.89; year 2: OR, 0.63; 95% CI, 0.50 to 0.78; year 3: OR, 0.81; 95% CI, 0.67 to 0.99). Conclusions: Newly diagnosed T2D patients have shown low rate of HbA1c and screening for diabetic-related complications and experienced inequality in relation to receiving qualitative diabetes care by income levels.