Cost-effectiveness of biennial screening for diabetes related retinopathy in people with type 1 and type 2 diabetes compared to annual screening

摘要

Objective Examine the health and economic impact of extending screening intervals in people with Type 2 diabetes (T2DM) and Type 1 diabetes (T1DM) without diabetes-related retinopathy (DR). Setting Diabetic Eye Screening Wales (DESW). Study design Retrospective observational study with cost-utility analysis (CUA) and Decremental Cost-Effectiveness Ratios (DCER) study. Intervention Biennial screening versus usual care (annual screening). Inputs Anonymised data from DESW were linked to primary care data for people with two prior screening events with no DR. Transition probabilities for progression to DR were estimated based on a subset of 26,812 and 1232 people with T2DM and T1DM, respectively. DCER above 20,000 pound per QALY was considered cost-effective. Results The base case analysis DCER results of 71,243 pound and 23,446 pound per QALY for T2DM and T1DM respectively at a 3.5% discount rate and 56,822 pound and 14,221 pound respectively when discounted at 1.5%. Diabetes management represented by the mean HbA(1c) was 7.5% for those with T2DM and 8.7% for T1DM. Sensitivity analysis Extending screening to biennial based on HbA(1c), being the strongest predictor of progression of DR, at three levels of HbA(1c) 6.5%, 8.0% and 9.5% lost one QALY saving the NHS 106,075; pound 58,653 pound and 31,626 pound respectively for T2DM and 94,696 pound, 37,646 pound and 11,089 pound respectively for T1DM. In addition, extending screening to biennial based on the duration of diabetes > 6 years for T2DM per QALY lost, saving the NHS 54,106 pound and for 6-12 and > 12 years for T1DM saving 83,856 pound, 23,446 pound and 13,340 pound respectively. Conclusions Base case and sensitivity analyses indicate biennial screening to be cost-effective for T2DM irrespective of HbA(1c) and duration of diabetes. However, the uncertainty around the DCER indicates that annual screening should be maintained for those with T1DM especially when the HbA(1c) exceeds 80 mmol/mol (9.5%) and duration of diabetes is greater than 12 years.