Similarly, the implausibly wide HF risk estimate for DPP-4 inhibitors versus SGLT-2 inhibitors (OR = 2.46; 95% CI, 0.24–24.73) stems from extreme data sparsity: only 3 trials43,56,69 (N = 1016) reported 3 total HF events (DPP-4 inhibitors: 2 vs SGLT-2 inhibitors: 1). This evidence concerns the gene DPP4 and hydrops fetalis.