Abstract 663: Circulating lipids and fatty acids and non-Hodgkin lymphoma risk in a nested case-control study: The Multiethnic Cohort (2012)

Abstract Objective: Dietary fatty acids provide important components of immune cells, cytokines, and prostaglandins. Intake of n-3 and n-6 polyunsaturated fatty acids may influence inflammatory responses that contribute to the risk of non-Hodgkin lymphoma (NHL). Because saturated and polyunsaturated fatty acid (SFA and PUFA) intake has been linked with NHL, this analysis evaluated biomarkers of dietary fat intake in relation to risk. Methods: We conducted a nested-case control analysis (275 cases and 549 controls) within the Multiethnic Cohort Study (Caucasians, Japanese Americans, Latinos, African Americans, and Native Hawaiians) to examine NHL risk by tertile of erythrocyte membrane fatty acid composition and serum lipid concentrations. Cases were matched to 2 controls by sex, year of birth, ethnicity, location (CA or HI), date and time of blood draw, and fasting hours before blood draw. Fatty acids were measured as the percentage of total measured erythrocyte membrane fatty acids using gas chromatography, and absolute serum levels of total, high density-lipoprotein (HDL), and low density-lipoprotein (LDL) cholesterol and triglycerides were measured using an automated chemical analyzer (Cobas MiraPlus, Roche Diagnostics, Switzerland). Conditional logistic regression was applied to estimate odds ratios (OR) and 95% confidence intervals (CI) with adjustment for potential confounders. Results: The mean ages at blood draw were 70.1±7.4 and 70.2±7.4 years for cases and controls, respectively. The cases (82 diffuse large B-cell, 52 small cell/chronic lymphocytic leukemia, 49 follicular, 15 T-cell, and 77 others) were diagnosed 3.1±2.3 years after the blood draw. Higher prediagnostic serum lipids, in particular total (ORT3 vs T1: 0.5 [95% CI: 0.4, 0.8]; ptrend &amp;lt;0.001) and HDL cholesterol (ORT3 vs T1: 0.5 [0.3, 0.8]; ptrend &amp;lt;0.01) but not triglycerides were associated with a lower NHL risk. No significant associations were found for individual fatty acids, the n-3/n-6 fatty acid or the PUFA/SFA ratio. Stratification by sex and ethnicity suggested significant heterogeneity. For example, in women but not in men, n-6 fatty acids were associated with a higher NHL risk (ptrend =0.09) and the PUFA/SFA ratio with a lower risk (ptrend =0.05). Monounsaturated fatty acids reduced risk in Caucasians (ptrend =0.01) while higher risks were observed for stearic acid (C18:0; ptrend &amp;lt;0.01) in Japanese Americans and for palmitic acid (C16:0; ptrend &amp;lt;0.01) in African Americans. Conclusions: Individual fatty acids showed no relation with overall NHL risk in this multiethnic population, but possible sex- or ethnicity-specific influences may exist. Total and HDL cholesterol levels, which reflect dietary and non-dietary factors, were associated with a reduced risk. Replication of these findings in other cohort studies is warranted. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 663. doi:1538-7445.AM2012-663