Hypertension and iron deficiency anemia: Exploring genetic associations and causal inference

Background and aim: Observational studies have suggested a potential association between hypertension and Iron deficiency anemia (IDA). However, it is unclear whether there is a genetic and causal link between hypertension and IDA. Methods and results: Genome-Wide Association Studies (GWAS) data for hypertension were sourced from the UK Biobank and FinnGen. Genetic variants data for IDA were extracted from FinnGen and the IEU Open GWAS project, all derived from European populations. The genetic association between hypertension and IDA was assessed using Linkage Disequilibrium Score Regression (LDSC), with MR employed to determine causality. Inverse variance weighted (IVW) as a major analytical method for MR. Sensitivity and heterogeneity analyses were conducted to ensure result reliability. Furthermore, validation analysis was performed to further strengthen the robustness of the findings. A genetic association between hypertension and IDA was observed (r(g) = 0.121, P = 0.002). Our findings suggest that hypertension increases the risk of developing IDA (OR = 2.493,P = 0.038), and IDA maybe serve as a risk factor for hypertension (OR = 1.006,P < 0.001). Validation analysis yielded consistent results. Importantly, our findings demonstrated no heterogeneity or horizontal pleiotropy. Conclusion: Additional insights into the connection between hypertension and IDA were gained. Regular testing of iron ions and anemia-related markers in hypertensive patients is crucial for early identification of IDA. Furthermore, it is imperative to closely monitor the blood pressure of patients with IDA to promptly identify and diagnose hypertension. The implementation of these integrated health strategies is vital for global efforts to tackle the dual challenges of hypertension and IDA.