Selenium, copper, zinc and hypertension: an analysis of the National Health and Nutrition Examination Survey (2011-2016)

Background Hypertension is a major cardiovascular illness worldwide with many underlying causes. The role of trace elements selenium, copper, and zinc in hypertension is uncertain. The objective of this study was to evaluate the role of these trace elements in hypertension. Method Data from 6683 National Health and Nutrition Examination Survey (NHANES) participants from 2011 to 2016 were analyzed using Statistical Analytical System (SAS, version 9.4) software for the role of trace elements in hypertension in age range 8 to 80 years, irrespective of the antihypertensive medication taken. Recent American Heart Association guidelines and pediatric practice guidelines for hypertension were used. Results Findings showed a significant positive association between serum selenium levels and hypertension but not serum zinc and copper. At optimal levels for transport and distribution, serum selenium levels of 120 mu g/L or higher (reference level 70-150 mu g/L) were significantly associated with hypertension (OR = 1.46, 95% CI = 1.29-1.66) after adjusting for confounding factors. At serum selenium level greater than 150 mu g/L, the association with hypertension strengthened (OR = 1.69, 95% CI = 1.32-2.17). Conclusion A positive association was found between serum selenium and hypertension, irrespective of age or anti-hypertensive medications intake. These findings also suggest that the reference levels of serum levels in healthy individuals may need to be re-determined, if supported by additional studies. If validated, patients with hypertension may also need to be cautioned about selenium intake.