Sodium-glucose co-transporter inhibitors in insulin-treated diabetes: a meta-analysis

Patients with insulin-treated type 2 diabetes (T2D) have a high risk of major adverse cardiovascular events. Sodium-glucose cotransporter inhibitors (SGLTi) improve outcomes without hypoglycaemic risk.

To study the effect of SGLTi in patients with T2D with and without background insulin treatment in outcome-driven RCTs.

Random effects models.

A total of 54 374 patients with T2D were included in the analysis, of which 26 551 (48.8%) were treated with insulin. For 3P-MACE in patients without insulin treatment, the HR (95% CI) for the effect of SGLTi vs placebo was 0.93 (0.81-1.05), with moderate heterogeneity (I2 = 49.2%, Q statistic P = 0.11). In insulin-treated patients, the HR (95% CI) was 0.88 (0.82-0.95), without evidence of heterogeneity (I2 =0.0%, Q statistic P =0.91). The pooled effect evidenced a 10% reduction of 3P-MACE with SGLTi (HR: 0.90, 95% CI: 0.85-0.96), without SGLTi-by-insulin interaction P = 0.53. For the composite outcome of HF hospitalisation or cardiovascular death in patients without insulin treatment, the HR (95% CI) for the effect of SGLTi vs placebo was 0.77 (0.61-0.92), with marked heterogeneity (I2 = 66.8%, Q statistic P = 0.02). In insulin-treated patients, the HR (95% CI) was 0.77 (0.68-0.86), without significant heterogeneity (I2 = 31.7%, Q statistic P = 0.25). The pooled effect evidenced a 23% reduction of HF hospitalisations or cardiovascular death with SGLTi (HR: 0.77, 95% CI: 0.68-0.85), without SGLTi-by-insulin interaction P = 0.98.

SGLTi reduces cardiovascular events regardless of insulin use. However, the treatment effect is more homogeneous among insulin-treated patients, supporting the use of SGLTi for the treatment of patients with T2D requiring insulin for glycaemic control.