Serum n-6 fatty acids and lipoprotein subclasses in middle-aged men: the population-based cross-sectional ERA-JUMP study.

BACKGROUND

The associations of serum omega-6 (n-6) fatty acids with lipoprotein subclasses at the population level are uncertain.

OBJECTIVE

We aimed to examine associations between major n-6 fatty acids [ie, linoleic acid (LA, 18:2n-6) and arachidonic acid (AA, 20:4n-6)] and the lipoprotein subclasses VLDL, LDL, and HDL.

DESIGN

We conducted a cross-sectional study in 1098 participants using population-based data from US white, Japanese American, Japanese, and Korean men aged 40-49 y. Serum fatty acids were analyzed by capillary gas-liquid chromatography. Lipoprotein subclasses were measured by nuclear magnetic resonance spectroscopy. Multiple linear regression models as a function of each fatty acid were used after adjustment for age, population, body mass index, pack-years of smoking, alcohol consumption, diabetes, hypertension, and omega-3 (n-3) and trans fatty acids.

RESULTS

Serum LA was inversely associated with large VLDL (beta = -0.62, P < 0.001), total LDL (beta = -22.08, P < 0.001), and small LDL (beta = -31.89, P < 0.001) particle concentrations and VLDL size (beta = -0.72, P < 0.001). Serum LA was positively associated with large HDL particle concentration (beta = 0.21, P < 0.001) and HDL size (beta = 0.03, P < 0.001). The patterns of association of AA with large VLDL and large HDL particle concentrations were comparable with those of LA.

CONCLUSIONS

At the population level, higher serum concentrations of LA were significantly associated with lower concentrations of total LDL particles. Higher serum concentrations of LA and AA were significantly associated with a lower concentration of large VLDL particles and a higher concentration of large HDL particles. These associations were consistent across the population groups. This trial was registered at clinicaltrials.gov as NCT00069797.