The Effects of Dapagliflozin in Patients With Heart Failure Complicated With Type 2 Diabetes: A Meta-Analysis of Placebo-Controlled Randomized Trials

BACKGROUND: Cardiovascular disease threatens the health and quality of life of individuals, particularly those with type II diabetes. Recently, some studies have reported the effect of sodium-glucose cotransporter 2 (SGLT2) inhibitors in reducing the rates of hospitalization or urgent visits, resulting in IV therapy for heart failure in patients with type 2 diabetes mellitus (T2DM). METHODS: We did a comprehensive search in electronic databases from inception through July 2020 for randomized-controlled trials, using the keywords “sodium-glucose cotransporter-2 inhibitor”, “dapagliflozin”, “heart failure”, “cardiovascular outcomes”, “major adverse cardiovascular events”, “all-cause mortality”, and “cardiovascular death”. Random-effects summary odds ratios (OR) were constructed using M-L heterogeneity model. RESULTS: Five trials with 5,252 patients were ultimately included. The incidence of hospitalization for heart failure (HHF) (n=4, OR=0.74; 95% CI, 0.61 to 0.88; I(2) = 0%) and all-cause mortality (ACM, n=4, OR=0.76; 95% CI, 0.66 to 0.94; I(2) = 0%); was reduced by dapagliflozin, respectively, in all heart failure patients, without obvious heterogeneity. The incidence of cardiovascular death in dapagliflozin was lower than that in placebo without statistically significant (CVD, n=5, OR=0.84; 95% CI, 0.69 to 1.03; I(2) = 0%). In HFrEF subgroup, dapagliflozin was associated with a reduced incidence of hospitalization for heart failure (n=4, OR=0.74; 95% CI, 0.60 to 0.91; I(2) = 0%), cardiovascular death (n=4, OR=0.72; 95% CI, 0.58 to 0.91; I(2) = 8%), and all-cause mortality (n=3, OR=0.70; 95% CI, 0.50 to 0.99; I(2) = 43%) without significant heterogeneity. In contrast, in the HFpEF subgroup, there was no difference in the incidence of cardiovascular death (n=2, OR=1.45; 95% CI, 0.95 to 2.22; I(2) = 0%) and all-cause mortality (n=2, OR=1.04; 95% CI, 0.76 to 1.43; I(2) = 0%) between dapagliflozin and placebo. CONCLUSION: In our study, dapagliflozin performed a statistical reduction in the rate of heart failure hospitalization, cardiovascular death, and all-cause mortality in patients with HFrEF and diabetes. However, in the HFpEF subgroup, dapagliflozin did not show a significant cardiovascular protective effect.