Effectiveness of monthly and bimonthly follow-up of patients with well-controlled type 2 diabetes: a propensity score matched cohort study

BACKGROUND: On average, patients in Japan with type 2 diabetes mellitus have a clinical consultation every month, although evidence for a favorable follow-up interval is lacking. This study investigated whether the follow-up interval can be extended by comparing the clinical outcomes and cost for monthly versus bimonthly follow-up of patients with well-controlled diabetes mellitus. METHODS: We combined administrative claims data from the National Health Insurance and the Health Checkups Program data of Tsu city, Japan between 2011 and 2014 to conduct a retrospective cohort study of patients with well-controlled type 2 diabetes mellitus. Propensity scores were used to assemble a matched-pairs cohort from patients who had monthly and bimonthly follow-up. Equivalence between two groups was assessed by designating the proportion of patients who maintained good control of their diabetes in the subsequent year as a primary outcome. The proportion achieving target blood pressure and lipid levels, favorable lifestyle, and annual cost were compared as secondary outcomes. RESULTS: Of 12,145 participants, 693 with monthly follow-up and 693 with bimonthly follow-up were matched using propensity scores. In the monthly follow-up group 654 (94.4%) remained under good diabetic control, versus 658 (95.0%) in the bimonthly group (difference: 0.6%; 95% confidence interval: − 1.8 to 2.9%). All secondary outcomes were equivalent for the monthly and bimonthly follow-up groups except the proportion achieving target blood pressure, the proportion engaging in regular exercise, and annual cost. CONCLUSIONS: For patients with well-controlled diabetes mellitus, although frequent follow-up by a physician does not affect the control of blood glucose level in the subsequent year, the annual treatment cost becomes much higher. We suggest that patients with well-controlled diabetes can be followed up less often.