Effect of canagliflozin on N-terminal pro-brain natriuretic peptide in patients with type 2 diabetes and chronic heart failure according to baseline use of glucose-lowering agents

Background: Sodium–glucose cotransporter 2 (SGLT2) inhibitors reduce the risk of a deterioration in heart failure (HF) and mortality in patients with a broad range of cardiovascular risks. Recent guidelines recommend considering the use of SGLT2 inhibitors in patients with type 2 diabetes (T2D) and HF, irrespective of their glycemic control status and background use of other glucose-lowering agents including metformin. However, only a small number of studies have investigated whether the effects of SGLT2 inhibitor in these patients differ by the concomitant use of other glucose-lowering agents. Methods: This was a post-hoc analysis of the CANDLE trial (UMIN000017669), an investigator-initiated, multicenter, open-label, randomized, controlled trial. The primary aim of the analysis was to assess the effect of 24 weeks of treatment with canagliflozin, relative to glimepiride, on N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration in patients with T2D and clinically stable chronic HF. In the present analysis, the effect of canagliflozin on NT-proBNP concentration was assessed in the patients according to their baseline use of other glucose-lowering agents. Results: Almost all patients in the CANDLE trial presented as clinically stable (New York Heart Association class I to II), with about 70% of participants having HF with a preserved ejection fraction phenotype (defined as a left ventricular ejection fraction ≥ 50%) at baseline. Of the 233 patients randomized to either canagliflozin (100 mg daily) or glimepiride (starting dose 0.5 mg daily), 85 (36.5%) had not been taking any glucose-lowering agents at baseline (naïve). Of the 148 patients who had been taking at least one glucose-lowering agent at baseline (non-naïve), 44 (29.7%) and 127 (85.8%) had received metformin or a dipeptidyl dipeptidase-4 (DPP-4) inhibitor, respectively. The group ratio (canagliflozin vs. glimepiride) of proportional changes in the geometric means of NT-proBNP concentration was 0.95 (95% confidence interval [CI] 0.76 to 1.18, p = 0.618) for the naïve subgroup, 0.92 (95% CI 0.79 to1.07, p = 0.288) for the non-naïve subgroup, 0.90 (95% CI 0.68 to 1.20, p = 0.473) for the metformin-user subgroup, and 0.91 (95% CI 0.77 to 1.08, p = 0.271) for the DPP-4 inhibitor-user subgroup. No heterogeneity in the effect of canagliflozin, relative to glimepiride, on NT-proBNP concentration was observed in the non-naïve subgroups compared to that in the naïve subgroup. Conclusion: The impact of canagliflozin treatment on NT-proBNP concentration appears to be independent of the background use of diabetes therapy in the patient population examined. Trial registration University Medical Information Network Clinical Trial Registry, number 000017669.