Change of selenium in environment and risk of adolescent idiopathic scoliosis: a retrospective cohort study.

OBJECTIVES: Scoliosis is the disease which has a long history over one century. However, the pathogenesis remains unclear at present. To demonstrate the effect of different selenium content in environment on the morbidity of adolescent idiopathic scoliosis (AIS). METHODS: Retrospective cohort study (follow-up from 1997 to 2009): compare the difference morbidity between high selenium group and the normal selenium group of AIS. PATIENTS: 9998 cases from three areas in China were participated in this study. There is different selenium content in these three areas. RESULTS: High selenium levels were significant associated with the AIS morbidity. While low selenium level had no significant correlation with the AIS morbidity. CONCLUSIONS: This study confirmed that high selenium content in the environment was one of risk factors for idiopathic scoliosis. We speculated that the excessive growth of the spine and the spinal cord asynchronous growth effect were key factors that high selenium content in the environment leads to scoliosis.