Ischemic Stroke Complicated by Acute Decompensated Heart Failure and Its Association with Hemoglobin Levels

BackgroundIschemic stroke (IS) is a serious complication in heart failure, particularly following hospitalization for acute decompensated heart failure (ADHF). However, its actual incidence during the acute and stable treatment phases remains unclear. Moreover, the association between IS and hemoglobin levels, which fluctuate during these phases, has not been comprehensively investigated. MethodsPatient-level data from 2018 to 2024 were extracted from a prospective multicenter cohort study that consecutively enrolled patients hospitalized with ADHF. Cerebrovascular events were confirmed by local board-certified neurologists using imaging modalities. The incidence of IS and its association with hemoglobin levels, categorized by the universal anemia definition (hemoglobin <13.0 g/dL for men and <12.0 g/dL for women) were examined in early (within 30 days) and late phases (beyond 30 days) following ADHF hospitalization. Fine-Gray models were used for early IS analyses, and Cox proportional hazards models with time-varying covariates (hemoglobin levels) were applied for late IS. Results: A total of 5,106 patients (median age 79 years; men 58%) were analyzed, and 115 (2.3%) developed IS over a median follow-up of 13 months. The incidence was higher in the early phase (median onset 7 days, p for trend=0.002). Cardioembolic stroke (61.7%) was the predominant subtype throughout phases. After covariate adjustments, higher hemoglobin levels (non-anemia) were associated with increased risk of early IS (sHR 2.05,95%CI 1.09- 3.83, p=0.03), but not with late IS (adjusted HR 1.21,95% CI 0.65-2.23, p=0.55), with restricted cubic spline further demonstrating non-linear phase-dependent differences in the impact of hemoglobin levels on IS risk. ConclusionIS occurred across phases of ADHF management, with higher incidence within 30 days after hospitalization. The relationship between hemoglobin levels and IS risk varies by phase, highlighting non-anemia as a potential marker for high-risk patients in the early phase. Incorporating hemoglobin levels into risk stratification could guide targeted screening and preventive strategies.