Plasma nutrient biomarkers of dietary intake in postmenopausal women with and without coronary heart disease (CHD): Insights from the Women's Health Initiative Observational Study (WHI‐OS)

The study aim was to quantify plasma nutrient biomarkers in WHI‐OS participants; cases with confirmed CHD (N=1214) and controls (N=1214) matched for age, enrollment date, race/ethnicity, and absence of CHD at baseline. Plasma phylloquinone, dihydrophylloquinone (dhK) and phospholipid (PL) fatty acid profiles were measured using HPLC and GC, respectively. Compared to controls, cases had higher plasma dhK and PL SFA; and lower PL eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) levels (all P<0.05). No significant differences were observed in plasma phylloquinone, PL MUFA, PUFA, omega‐6 or trans fatty acid levels. In multivariate conditional logistic regression analyses controlling for BMI, systolic blood pressure, smoking, education, medication/hormone use, family history of CVD/diabetes and leisure physical activity ‐ plasma dhK (2.2 [1.0–4.7]) and PL SFA (1.2 [1.1–1.3]) were associated with higher CHD risk, whereas EPA (0.7 [0.6–0.9]) and DHA (0.6 [0.4–0.8]) were associated with lower CHD risk (values are odds ratio [95%CI]; all P<0.01). These data suggest that plasma dhK and PL omega‐3 fatty acid levels, nutrient biomarkers indicative of partially hydrogenated fat and fish intake respectively, are independent predictors of CHD risk in this population. (NIH‐HHSN268200764317, ADB contract #: N01‐WH‐74317).