Evaluating serum alpha-tocopherol (vitamin E) in terms of a lipid ratio
Winbauer, A.N.; Pingree, S.S.; Nuttall, K.L.
Annals of Clinical and Laboratory Science 29(3): 185-191
1999
ISSN/ISBN: 0091-7370 PMID: 10440582 Document Number: 503659
It is well known that accurate assessment of serum alpha-tocopherol requires knowledge of the serum lipids also present. Patient specimens (n = 307) within the standard reference limit of 5-18 mg/L were used to determine the following 95 percent reference interval for a lipid ratio of alpha-tocopherol to the sum of cholesterol and triglycerides (E/(C + T)): 1.4 (1.20-1.56) - 5.7 (5.51-6.91) mg/g (90 percent confidence interval). In terms of alpha-tocopherol status, patients with low results (<5 mg/L) were normal on reevaluation with the lipid ratio in 47 percent of those examined (28 of 59), and elevated results (>18 mg/L) were normal or low in 58 percent (26 of 45). Elevated triglycerides developed from non-fasting specimens were one common reason for misleading results when lipids were not considered. When measuring alpha-tocopherol in a patient population, evaluation of the lipid content is needed for accurate assessment in a significant number of cases.