Association of Selenium Levels with Neurodegenerative Disease: A Systemic Review and Meta-Analysis

Background: Neurodegenerative diseases (NDs) have posed significant challenges to public health, and it is crucial to understand their mechanisms in order to develop effective therapeutic strategies. Recent studies have highlighted the potential role of selenium in ND pathogenesis, as it plays a vital role in maintaining cellular homeostasis and preventing oxidative damage. However, a comprehensive analysis of the association between selenium and NDs is still lacking. Method: Five public databases, namely PubMed, Web of Science, EMBASE, Cochrane and Clinical Trials, were searched in our research. Random model effects were chosen, and Higgins inconsistency analyses (I(2)), Cochrane’s Q test and Tau2 were calculated to evaluate the heterogeneity. Result: The association of selenium in ND patients with Alzheimer’s disease (AD), Parkinson’s disease (PD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS) and Huntington’s disease (HD) was studied. A statistically significant relationship was only found for AD patients (SMD = −0.41, 95% CI (−0.64, −0.17), p < 0.001), especially for erythrocytes. However, no significant relationship was observed in the analysis of the other four diseases. Conclusion: Generally, this meta-analysis indicated that AD patients are strongly associated with lower selenium concentrations compared with healthy people, which may provide a clinical reference in the future. However, more studies are urgently needed for further study and treatment of neurodegenerative diseases.