Characteristics, Treatment Patterns, and Economic Outcomes of Patients Initiating Injectable Medications for Management of Type 2 Diabetes Mellitus in Japan: Results from a Retrospective Claims Database Analysis

INTRODUCTION: This study’s objective was to describe characteristics, treatment patterns, and economic outcomes of type 2 diabetes mellitus (T2DM) patients initiating injectable antidiabetic medications in Japan. METHODS: Adults (≥ 18 years) with T2DM, ≥ 2 claims for injectable antidiabetics between 1 August 2011 and 31 July 2015 (first claim = index date), no evidence of type 1 diabetes mellitus, ≤ 1 claim for insulin, no claims for GLP-1RA before index, and continuous enrollment for 6 months before (baseline) and 12 months after index (follow-up) were selected from the Japan Medical Center Database. Patient characteristics and outcomes during the baseline and follow-up periods were described overall and by provider, using the proxy setting of index medication [hospital (including outpatient departments) for specialists; clinic for general practitioner (GP)]. RESULTS: Of the 2683 patients included (mean age: 50 years, 67% male), 1879 (70%) initiated injectable antidiabetics with specialists and 804 (30%) with GPs. The specialist cohort had a significantly greater comorbidity burden, but lower HbA1c levels during baseline, and was more likely to receive intensified treatment at index than the GP cohort. Almost 40% of patients (almost 30% of GP cohort) did not use antidiabetics during baseline; the remaining patients received oral medications, primarily from GPs. During follow-up, patients used the index medication for approximately 7 months. Independent of specialist vs. GP setting, patients received antidiabetics and medications for T2DM-related comorbidities and complications during the baseline and follow-up periods from the same provider, primarily GPs. The overall average healthcare costs were ¥350,404 during baseline and ¥1,856,727 during follow-up. CONCLUSIONS: In Japan, most T2DM patients initiated injectable antidiabetics with specialists vs. GPs. There were considerable differences in characteristics of patients treated by specialists vs. GPs. After initiation, injectable antidiabetics were largely prescribed by GPs. Future research should evaluate the factors associated with different provider practices and communication channels between specialists and GPs to improve patient management. FUNDING: Eli Lilly and Co.