Comparative effectiveness of dapagliflozin vs DPP-4 inhibitors on a composite endpoint of HbA1c, body weight and blood pressure reduction in the real world

Background: Treatment of type 2 diabetes (T2D) should aim at preventing or delaying complications through the control of glycaemia and cardiovascular risk factors. We herein compared the SGLT-2 inhibitor dapagliflozin vs DPP-4 inhibitors (DPP-4i) on a composite endpoint of glycaemic and extraglycaemic effectiveness. Methods: This was a multicentre, retrospective real-world study conducted at 56 outpatient clinics in Italy. We collected data on patients newly started on dapagliflozin or DPP-4i in 2015-2017. The primary endpoint was the proportion of patients attaining a simultaneous reduction of HbA1c ≥0.5%, body weight ≥2 kg, systolic blood pressure (SBP) ≥2 mmHg. Confounding by indication was addressed by propensity score matching (PSM) or multivariable adjustment (MVA). Results: Patients initiating dapagliflozin (n = 2091) or DPP-4i (n = 2144) differed for most clinical characteristics. After PSM, two well-balanced groups of 1149 patients each were compared. The primary endpoint was reached in a greater proportion of patients who received dapagliflozin (17.6%) compared to DPP-4i (11.7%), with a relative risk of 1.50 (1.21-1.86; P <.001). Similar results were obtained in the as-treated and intention-to-treat datasets or using MVA in place of PSM. The beneficial effect of dapagliflozin was mainly due to its greater effectiveness on body weight and, to a lesser extent, on SBP. The change in HbA1c did not differ between groups. Conclusions: T2D patients initiating the SGLT2i dapagliflozin had a greater probability of attaining a composite endpoint of clinically relevant reductions in HbA1c, body weight and SBP, compared to similar patients initiating a DPP-4i in the same period and healthcare setting.