Analysis of the association between hemoglobin and hyperuricemia by NHANES database and Mendel randomization

Background The relationship between hemoglobin and hyperuricemia is still unclear. Objective To explore the association between hemoglobin and hyperuricemia. Methods The data for our cross-sectional study were obtained from the National Health and Nutrition Examination Survey (NHANES) 2011–2020. Weighted multivariate logistic regression was performed to examine the association between hemoglobin and hyperuricemia. Inverse variance weighted (IVW), weighted-median, weighted-mode and MR-Egger were used in MR analyses to assess the causal relationship between hemoglobin and hyperuricemia. Heterogeneity and horizontal pleiotropy were evaluated using Cochrane Q-test and MR Egger intercept test, respectively. Sensitivity analysis was conducted using Leave one out to evaluate the bias of individual SNPs in MR analysis. All analyses were carried out using IBM SPSS 24.0 and R version 4.3.1. Results A total of 21,855 NHANES participants were included in this study. After adjusting for all covariates, the association between hemoglobin and hyperuricemia was signifcant ( P  < 0.05). IVW estimates revealed that hemoglobin had signifcant efect on the risk of hyperuricemia (OR = 1.0329487, 95% CI = 1.005145–1.061521, P  < 0.05). Findings of MR Egger regression, weighted median method and weighted mode were consistent with those from IVW (weighted median: OR = 1.056927, 95% CI = 1.029481–1.085105; P  < 0.05; MR-Egger: OR = 1.0776376, 95% CI = 1.022953–1.135246, P  < 0.05; Weighted mode: OR = 1.047532, 95% CI = 1.02109–1.074639, P  < 0.05). The results of three MR Analyses methods also showed causal association between hemoglobin and hyperuricemia. Conclusions Our findings support a causal association between hemoglobin and hyperuricemia. This suggests that monitoring hemoglobin levels is equally important in preventing the occurrence of hyperuricemia.