BACKGROUND: Common variable immunodeficiency (CVID) is an inborn errors of immunity, that leads to recurrent chronic infections and autoimmune/ inflammatory diseases and neoplasms. It is considered that these condition is related to persistent this immune-inflammatory stimulation and increased oxidative stress. A positive impact on the survival of patients with an inborn error of immunity was observed with advanced clinical care protocols, thus raising concerns about the risk of developing other associated chronic diseases, such as atherosclerosis. Studies suggest that selenium (Se) is a protective trace element against damage caused by oxidative stress. Thus, it is postulated that adequate consumption reduces the risk of some chronic diseases. RESULTS: Se median levels (ug/L) [45.6 (37.3-56.2) vs. 57.8 (46.0-66.0); p = 0.004] and GPX activity (U/L) [7682 (6548-8446) vs. 9284(8440-10,720); p = 0,002) were significantly lower in patients compared to controls. Inadequacy of Se levels was observed in 50% of the patients. There was a higher percentage of high values of C-reactive protein in the group of CVID patients compared to controls [8 (36.4%) vs. 2 (11.1%); p = 0.082]. Higher concentrations of oxidized LDL (45.3 mg/dL vs. 33.3 mg/dL; p = 0.016) and lower concentrations of Apo A-1 (98.5 mg/dL) vs. 117.0 mg/dL; p = 0.008) were observed in the CVID group compared to the control. There was a significant and positive correlation between Se plasma levels and apolipoprotein A-1 concentrations in CVID group (rho = 0.577; p = 0.001). Se values less than 46 µg / L (OR = 3.590; 95% CI 1.103 to 11.687; p = 0.034) and GPX activity below the 4th quartile (OR = 21.703; 95% CI 2.534 to 185.914; p = 0.005) were independently associated, after adjustment for age, overweight and dyslipidemia, with the CVID group (Table 5). CONCLUSION: This study showed an higher percentage of high us-CRP, lower values of plasma Se and GPX activity, higher concentrations of LDLox and lower levels of Apo A-1 in CVID patients in comparison to controls, suggesting oxidative stress and cardiovascular risk.These data point to the importance of assessing the Se status and cardiovascular risk in these patients.