GDF15 and hydrops fetalis: Two studies also evaluated the effect size of GDF-15 and HF hospitalisation (Yin et al., 2023; Lyu et al., 2024), with a pooled HR of 1.76 (95% CI [1.30–2.38]; p < 0.01; I2 0%) (Fig. 4C), indicating a significant association between elevated GDF-15 levels and increased risk of HF hospitalisation.