The establishment of tocopherol reference intervals for Hungarian adult population using a validated HPLC method.
Evidence suggests that decreased α-tocopherol (the most biologically active substance in the vitamin E group) level can cause neurological symptoms, most likely ataxia. The aim of the current study was to first provide reference intervals for serum tocopherols in the adult Hungarian population with appropriate sample size, recruiting healthy control subjects and neurological patients suffering from conditions without symptoms of ataxia, myopathy or cognitive deficiency. A validated HPLC method applying a diode array detector and rac-tocol as internal standard was utilized for that purpose. Furthermore, serum cholesterol levels were determined as well for data normalization. The calculated 2.5-97.5% reference intervals for α-, β/γ- and δ-tocopherols were 24.62-54.67, 0.81-3.69 and 0.29-1.07 μm, respectively, whereas the tocopherol/cholesterol ratios were 5.11-11.27, 0.14-0.72 and 0.06-0.22 μmol/mmol, respectively. The establishment of these reference intervals may improve the diagnostic accuracy of tocopherol measurements in certain neurological conditions with decreased tocopherol levels. Moreover, the current study draws special attention to the possible pitfalls in the complex process of the determination of reference intervals as well, including the selection of study population, the application of internal standard and method validation and the calculation of tocopherol/cholesterol ratios.
Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary.|MTA-SZTE Neuroscience Research Group, Szeged, Hungary.
Gábor
G
Veres
Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary.
László
L
Szpisjak
Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary.
Attila
A
Bajtai
Department of Laboratory Medicine, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary.
Andrea
A
Siska
Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary.
Péter
P
Klivényi
Department of Inorganic and Analytical Chemistry, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary.
István
I
Ilisz
Department of Laboratory Medicine, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary.
Imre
I
Földesi
Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary.|MTA-SZTE Neuroscience Research Group, Szeged, Hungary.
László
L
Vécsei
Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary.
Dénes
http://orcid.org/0000-0003-0749-7980
D
Zádori
D000328:Adult; D000368:Aged; D002784:Cholesterol / Q000097:blood; D002851:Chromatography, High Pressure Liquid / Q000379:methods* / Q000592:standards*; D005260:Female; D006801:Humans; D006814:Hungary; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D015203:Reproducibility of Results; D024505:Tocopherols / Q000097:blood*; D055815:Young Adult
D002784:Cholesterol; D024505:Tocopherols
HPLC; cholesterol; human samples; reference interval; tocopherol