Journal Article

Comparative effectiveness of biguanides versus SGLT2 inhibitors on cardiovascular and cerebrovascular events, diabetic nephropathy, retinopathy, neuropathy, and treatment expenditures in patients with type 2 diabetes

Ohata, Emi, Sugawara, Akira, Satoh, Tatsunori, Ueki, Chikara, Igarashi, Ataru, Kumamaru, Hiraku, Ohno, Hiromitsu, Nakatani, Eiji, Matsunaga, Taku, Nagahama, Takayoshi, Kaneda, Hideaki, Yui, Hiromichi, Miyakoshi, Akinori, Tonoike, Toru, Funaki, Daito, Tanaka, Yoshihiro

2025

Overview

Sodium-glucose cotransporter-2 (SGLT2) inhibitors are increasingly recommended as first-line treatment for type 2 diabetes mellitus (T2DM), but head-to-head data comparing them with metformin, the canonical biguanide, remain sparse in Japan. To compare the long-term effectiveness and cost of initiating treatment with a biguanide versus an SGLT2 inhibitor, excluding the alternative class for 12 months but permitting other antidiabetic drugs, on a composite of major cardio-cerebrovascular events and all-cause death, and a composite of diabetic complications. We emulated a new-user cohort trial using the Shizuoka Kokuho Database (2014-2021). Patients initiating treatment with either a biguanide or an SGLT2 inhibitor, while avoiding the alternative class during the first 12 months but allowing other glucose-lowering agents, were included. Follow-up began at treatment initiation; those who received the comparator drug within 12 months were excluded. After 1:1 propensity-score matching on demographic, clinical, laboratory, and lifestyle variables, cause-specific Cox models estimated hazard ratios (HRs). Daily medication costs were compared. After matching, 1,246 patients (623 per group) were followed for a median of 2.9 years (maximum 7.2 years). Cardio-cerebrovascular composite: 44/623 biguanide users (7.1%) and 35/623 SGLT2 inhibitor users (5.6%) experienced a first event (HR 0.80, 95% CI 0.51-1.24). Diabetic complications: 86/623 (13.8%) vs. 78/623 (12.5%) (HR 0.88, 95% CI 0.70-1.13). Median daily drug cost was 124.7 JPY for biguanides and 184.0 JPY for SGLT2 inhibitors (P < 0.001). Using a large-scale regional database from Japan, we found that among adults with type 2 diabetes without prior major cardiac or renal disease, first-line treatment with an SGLT2 inhibitor did not reduce risks of cardio-cerebrovascular events, mortality, or complications compared with metformin, and cost about 50% more.

• Publisher: Public Library of Science
• Subject: Care and treatment / Comparative analysis / Dapagliflozin / Dextrose / Diabetes therapy / Diabetic retinopathy / Glucose / Kidney diseases / Type 2 diabetes