Selenium Nutritional Status and Glutathione Peroxidase Activity and Its Relationship with Hemodialysis Time in Individuals Living in a Brazilian Region with Selenium-Rich Soil.

Suboptimal selenium status may impair the antioxidant defense system in patients undergoing hemodialysis, compromising the selenoenzyme glutathione peroxidase activity. To evaluate the association between the duration of hemodialysis, nutritional selenium status, glutathione peroxidase activity (GPx), and thiobarbituric acid reactive substance (TBARS) levels in patients with chronic renal failure undergoing hemodialysis in a region of selenium-rich soils (Ceará, Northeast Brazil). The case-control study of 75 individuals aged 18 to 88 years was allocated between two groups: hemodialysis (n = 41) and control (n = 34).