Multi-Omics-Based Sex Stratification Identifies Distinct High-Risk Phenotypes in HFpEF

Background. Heart failure with preserved ejection fraction (HFpEF) accounts for more than half of heart failure cases and is characterized by substantial clinical and biological heterogeneity. Sex differences are central to HFpEF pathophysiology, yet current phenotyping approaches often aggregate women and men, potentially obscuring distinct molecular mechanisms of disease progression. Molecularly resolved, sex-specific stratification is therefore needed to identify divergent risk pathways and improve biological understanding of HFpEF heterogeneity. Methods. In 698 HFpEF participants from the prospective MyoVasc cohort (379 females, 319 males), we run separate analyses on sex-specific cohorts. For each cohort, we integrated 92 circulating proteins (Olink Inflammation panel) and 49 clinical variables using Similarity Network Fusion to construct sex-stratified patient-patient similarity networks. Spectral clustering identified sex-specific prognostic subgroups related to the primary endpoint, i.e. worsening of Heart Failure (WHF). XGBoost models characterizing cluster-defining features were validated in an independent cohort of 342 HFpEF patients from the Gutenberg Health Study (GHS; 194 females, 148 males). Results. Two clusters emerged in each sex, with high-risk and low-risk clusters, showing the difference in WHF risk (MyoVasc females: HR 2.45, 95% CI 1.32-4.54, p=0.005; males: HR 2.77, 95% CI 1.27-6.04, p=0.011; C-index 0.62-0.63). Kaplan-Meier analyses confirmed separation (p<0.02 females, p<0.01 males). Clusters were reproduced in GHS using MyoVasc-trained XGBoost (females p=0.0082, males p=0.037). Shared top-ranking features included VEGF-A, TNFRSF9, and TGF-. Females were characterized by inflammatory (CD40, HGF, TNF) and glycemic signatures, whereas males showed prominence of immune-regulatory markers (IL-10RB, PD-L1) and renal function indicators (eGFR, creatinine). Conclusions. Sex-stratified molecular-clinical networks define prognostically distinct HFpEF subgroups with robust external validation. Shared protein biomarkers alongside sex-specific drivers reveal complementary progression mechanisms, supporting precision medicine strategies targeting high-risk cluster patients in sex-specific manner.