Impact of Initial Treatment Policies on Long-term Complications and Costs in Japanese Patients with Type 2 Diabetes: A Real-World Database Study.

Introduction: Type 2 diabetes (T2D) represents a remarkable disease burden in Japan, and the cost-effectiveness of pharmacotherapy is an important consideration. In this study, we compared the long-term effects of the type of initial medication, as well as the initial frequency of clinic visits, on the occurrence of T2D-related complications. Additionally, we compared the medical costs associated with each treatment pattern.

Methods: We analyzed electronic health record data collected from multiple primary care clinics in Japan. Patients were selected based on being primarily prescribed either biguanides (BG) or DPP-4 inhibitors (DPP-4i) during a 3-month baseline period, both of which are commonly used as first-choice medications in Japan. We then followed the onset of T2D-related complications and conducted survival analyses. Additionally, we calculated the accumulated medical costs up to the onset of an event or loss to follow-up, and summarized the annual costs per patient for each treatment pattern.

Results: A total of 416 Japanese patients with T2D who initiated treatment between January 2015 and September 2021 were included. The median follow-up period was 2.69 years. The survival analysis showed that the use of DPP-4is and frequent visits from the beginning of treatment did not offer a benefit in suppressing the onset of complications later on. On the other hand, it was found that the annual medical costs for the group using DPP-4i with frequent visits were about 1.9 times higher than for the group using BGs with less frequent visits.

Conclusions: The results suggest that for Japanese patients with T2D, the use of BGs along with relatively long follow-up intervals in the beginning of treatment can remarkably reduce medical costs while providing a level of complication suppression equivalent to that of the use of DPP-4is or frequent visits.