Conclusions

The present study demonstrated a significant unadjusted association between iron deficiency and greater heart failure severity among HFpEF patients, reflected by higher NYHA functional class, markedly elevated NT-proBNP levels, and more advanced echocardiographic diastolic dysfunction. Anaemia was also substantially more frequent among iron-deficient patients. However, given the observed baseline imbalances in age and anaemia status between groups and the absence of multivariable adjustment, these findings should be considered hypothesis-generating rather than confirmatory of an independent effect of iron deficiency. Nonetheless, they underscore the potential clinical relevance of routine iron status assessment in HFpEF management, particularly in resource-limited settings such as Bangladesh. Further prospective, multicenter studies with larger sample sizes and multivariable adjustment are warranted to establish causal relationships, clarify the independent contribution of iron deficiency, and evaluate the therapeutic impact of iron repletion in this population.