Prediagnostic Serum Tocopherol Levels and the Risk of Non-Hodgkin Lymphoma: The Multiethnic Cohort

Abstract

Background Compromised immunity and chronic inflammation are thought to contribute to the development of non-Hodgkin lymphoma (NHL). Because tocopherols protect cells through antioxidant mechanisms, they may play a role in NHL etiology. Methods This nested case-control study within the Multiethnic Cohort examined the association of prediagnostic serum tocopherols levels measured in 271 NHL cases and 538 matched controls by high pressure liquid chromatography/photodiode-array detection with NHL risk. Conditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CI). Results We observed U-shaped associations with NHL for total and α-tocopherols (Ptrend<0.01 for polynomial terms [3 df]). The ORs (95% CI) for total tocopherols, which consisted primarily of α-tocopherol, were 0.41 (0.25–0.68), 0.52 (0.32–0.85), 0.39 (0.23–0.65), and 0.78 (0.47–1.29) for the 2nd-5th quintiles as compared to the 1st. The risk estimates were similar for α-tocopherol but non-significant for β- and γ-tocopherol combined and for δ-tocopherol. Adjustment for serum lipids strengthened the non-linear associations for total and α-tocopherols. Serum total tocopherol levels were higher for vitamin E supplement users at cohort entry than non-users (21.32±9.04 vs 17.72±7.43 μg/mL; P <0.0001), but supplement use was not associated with NHL risk. No heterogeneity in risk estimates was detected by sex, ethnicity, vitamin E supplement use, or NHL subtype. Conclusions Circulating tocopherols, at levels likely reflecting adequate dietary intakes, may be protective against NHL, whereas higher intakes from supplementation may not be beneficial. Impact The association between serum tocopherol levels and NHL risk provides possible new insights into the etiology of NHL.

Association of serum γ-tocopherol levels with mortality: the Multiethnic Cohort Study

“…Epidemiological evidence regarding associations of γ-tocopherol with aging and the etiology of aging related diseases is limited and results are equivocal. While some studies reported inverse associations of γ-tocopherol with certain types of cancers [18–20], null [21–23] or positive associations have been found in others [20, 24]. Further, a nested case-control study with 39,242 Japanese subjects found that serum γ-tocopherol levels were inversely associated with ischemic stroke mortality in men but positively associated with hemorrhagic stroke mortality in women [25].…”