Subgroup analysis showed that SGLT-2 inhibitors improved the VO<sub>2</sub>peak in non-HF patients (WMD, 3.57 ml kg<sup>-1</sup> min<sup>-1</sup>, 95% CI: 0.87-6.26, and <i>p</i> = 0.009; I<sup>2</sup> = 4% and <i>p</i> = 0.31) more than in HF patients (WMD, 1.46 ml kg<sup>-1</sup> min<sup>-1</sup>, 95% CI: -0.13-3.04, and <i>p</i> = 0.07; I<sup>2</sup> = 0% and <i>p</i> = 0.81). Here, SLC5A2 is linked to hydrops fetalis.