Relationship between hemoglobin and lung cancer: evidence from Mendelian randomization and National Health and Nutrition Examination Survey

BackgroundLung cancer is the primary cause of cancer-related mortality worldwide. Hemoglobin (Hb) represents the most widely utilized test parameter in clinical settings. However, few articles have examined the causal relationship between Hb concentration and lung cancer incidence.MethodsMendelian randomization (MR) was first conducted to investigate the potential causality between Hb and lung cancer. Sensitivity analyses were applied to validate the reliability of MR results. Then, the National Health and Nutrition Examination Survey (NHANES) database was used to verify the effect of Hb on the prognosis of lung cancer.ResultsThe MR analysis demonstrated that Hb was casually associated with the decreased risk of lung cancer in the European population (ORIVW 0.84, 95% CI 0.75-0.95, p = 0.006; ORWeighted-median 0.78, 95% CI 0.65-0.94, p = 0.008; ORMR-Egger 0.82, 95% CI 0.64-1.04, p = 0.11). The results from the NHANES database showed that a high value of Hb was associated with better outcomes for patients with lung cancer (HR 0.45, 95% CI 0.26-0.79, p = 1.6E-03).ConclusionsOur study provides further evidence for the relationship between Hb levels and lung cancer, highlighting the potential significance of Hb as a biomarker for predicting the risk and prognosis of lung cancer.