Is selenium deficiency really the cause of Keshan disease?

Keshan disease (KD) is a dilated cardiomyopathy closely related with a diet deficient in the mineral selenium. It is named for the northeastern Chinese county Keshan, where the disease prevalence is high because of selenium-deficient soil. KD is a gene-environment interaction disease. Here, we used stepwise multiple regression analysis to analyze the risk factors of the disease and the main clinical features in 71 KD patients and 290 controls. The variables analyzed included age, sex, family history of KD, blood selenium level, glutathione peroxidase-1 (GPx-1) activity, variance at codon198 in GPx-1 gene, residence in an endemic area, abnormal electrocardiography (ECG) findings, and cardiothoracic (CT) ratio. The main risk factors found were low GPx-1 activity, family history of KD and living in an endemic area. The main clinical features were increased cardiac load on ECG and increased CT ratio and Tei index. Public health and clinical prevention efforts could focus on increasing GPx-1 activity to address KD. Is selenium deficiency really the certain cause of KD? This is not at all a settled question. And further study is promptly required to investigate the etiology of KD.