Effectiveness and cost-effectiveness of 3-monthly versus 6-monthly monitoring of well-controlled type 2 diabetes patients: a pragmatic randomised controlled patient-preference equivalence trial in primary care (EFFIMODI study)

Aim To investigate effectiveness and cost‐effectiveness of 6‐monthly monitoring compared with 3‐monthly monitoring of well‐controlled type 2 diabetes patients in primary care. Methods A pragmatic randomised controlled patient‐preference equivalence trial was performed. From April 2009 to August 2010, 2215 patients from 233 general practitioners across the Netherlands were included. Patients were eligible if between 40‐ and 80‐years‐old, diagnosed with type 2 diabetes for more than a year, treated by their general practitioner, not on insulin treatment and well‐controlled during the last year (HbA1c ≤58 mmol/mol, systolic blood pressure ≤145 mmHg and total cholesterol ≤5.2 mmol/l). Patients without a strong preference for their monitoring frequency were randomised to 3‐monthly or 6‐monthly monitoring. Follow‐up was 18 months. The primary outcome is the percentage of patients remaining under: HbA1c ≤58 mmol/mol, systolic blood pressure ≤145 mmHg and total cholesterol ≤5.2 mmol/l. Equivalence was assumed if the two‐sided 95% confidence interval (CI) was between −5 and 5%. Cost‐effectiveness was determined using a cost‐minimisation analysis. Results In the 3‐monthly group 69.5% remained under good cardiometabolic control, versus 69.8% in the 6‐monthly group (difference: 0.3%; 95%CI: −6.2–6.7%). All secondary outcomes were equivalent for 3‐monthly and 6‐monthly monitoring, except the systolic blood pressure target, physical activity and antihypertensive drug use. Six‐monthly monitoring was €387 (£333) cheaper per patient compared to 3‐monthly monitoring during the study period. Conclusions Patients with good cardiometabolic control and without preference for their monitoring frequency can visit the primary care physician less often. The cost‐savings can be considerable.