Abstract MP25: Circulating Odd-Chain Fatty Acids and Mortality Risk After Myocardial Infarction in the Alpha Omega Cohort

Abstract

Background: Circulating odd-chain fatty acids (OCFAs) 15:0 and 17:0, potential biomarkers of dairy (fat) intake, have been associated with cardiometabolic outcomes in population-based studies. Whether circulating OCFAs are related to mortality risk in patients who experienced a myocardial infarction (MI) is not yet clear. Methods: We included 4,741 Dutch patients aged 60-80 y (78% males) from the Alpha Omega Cohort, who experienced a myocardial infarction (MI) up to 10 years prior to study enrolment. At baseline (2002-2006), data were obtained on risk factors for cardiovascular disease (CVD), medication, lifestyle factors and dietary intakes (203-item FFQ). Fatty acids in serum cholesteryl esters (CE) were assessed using gas chromatography. Multivariable Cox models were used to obtain hazard ratios (HRs) and 95% confidence intervals (CI) for total and CVD mortality in relation to 15:0 and 17:0 in CE (per 10 th to 90 th percentile range, P 10-90 ). HRs were adjusted for age, sex, education, BMI, physical activity, diabetes, other CVD risk factors, medication, circulating linoleic acid, circulating EPA+DHA, and dietary factors. Missing data imputation was performed for confounders. Findings: Most patients used cardiovascular drugs (statins: 85%) and 979 patients (21%) had diabetes. During a median follow-up period of 12.4 years (total of 52,625 person-years), 2,233 patients died, of whom 984 from CVD. Circulating levels (% of total fatty acids) were low for 15:0 (median: 0.16; P 10-90 : 0.11-0.21) and 17:0 (median: 0.08; P 10-90 : 0.00-0.11). For 15:0, age and sex adjusted HRs per P 10-90 were 0.88 (95% CI: 0.81-0.95; P =0.001) for total mortality and 0.94 (0.83-1.06) for CVD mortality. In the most adjusted model, HRs for 15:0 were 0.92 (0.84-1.00; P =0.042) and 0.97 (0.85-1.11), respectively. For 17:0, HRs were 0.94 (0.85-1.05) for total mortality and 0.97 (0.83-1.13) for CVD mortality. Stratified analyses by sex showed inverse associations for 15:0 mainly in men (total mortality: HR of 0.90 [0.82-1.00]; P =0.047). For 17:0, inverse but non-significant associations were mainly observed in women (total mortality: HR of 0.85 [0.68-1.05]). Associations for 17:0, but not for 15:0, were stronger in diabetic patients (total mortality: HR of 0.78 [0.64-0.96]; P =0.019). Conclusions: Higher circulating OCFA levels may be related to a lower mortality risk after MI, which needs confirmation in other cohorts of CVD patients. The role of dairy fat intake in this relationship warrants further investigation.