RESUMO
While several small studies have found that selenium deficiency is associated with low platelet counts, they lack generalizability. We used data from the National Health and Nutrition Examination Surveys collected over a 12-year period. We examined the relationship between selenium quartiles and platelet count using survey-weighted linear regression models adjusting for age, sex, race, household income to poverty threshold income, highest education attainment, smoking status, red blood cell folate, and body mass index. Of the 21,764 participants, 51% were females, 23% African Americans, and 25% were >65 years of age. Mean (SD) platelet count was 243(64) 109/L and selenium was 183(32) µg/L. Women had significantly higher platelet count but lower selenium levels than men (258 vs. 227 109/L and 181 vs. 185 µg/L respectively; both P < 0.0001). In adjusted analysis, participants in the highest selenium quartile had 8.0x109/L higher platelet count as compared to those in the lowest selenium quartile (95%CI = 4.1 to 11.9; P < 0.0001). Gender modified the relationship between the two; although there was no difference in women, platelet count was higher in the highest than the lowest selenium quartile in men (interaction p-value = 0.001). These findings highlight the importance of selenium and gender in platelet biology which needs to be explored.
Several small studies have found an association between selenium deficiency and low platelet counts but a large study is needed. We examined this association using data from the National Health and Nutrition Examination Surveys while adjusting for age, sex, race, household income to poverty threshold income, highest education attainment, smoking status, red blood cell folate, and body mass index. In this cohort of 21,764 participants, we found that participants in the highest selenium quartile had significantly higher platelet count than those in the lowest quartile and that this relationship between selenium and platelet count differs by gender. Our findings highlight the importance of both selenium and gender in platelet biology which needs further exploration.