Erythrocyte odd-chain fatty acids and the risk of cardiometabolic diseases: a prospective study and updated meta-analysis.

Abstract

Aim: To determine dietary sources of odd-chain fatty acids (OCFAs) in Asians and their associations with cardiometabolic diseases (CMDs) and to compare these associations with other populations.

Methods: Erythrocyte fatty acids were profiled in 8,185 subjects (38% men, mean age 58.1 years) participating in the 2nd resurvey of the China Kadoorie Biobank (CKB) in 2013-14 using gas chromatography. Correlations of pentadecanoic (15:0) and heptadecanoic (17:0) acids with dietary factors, assessed via food frequency questionnaires, were examined by Spearman correlations. During about 5-year follow-up, 950 incident CMD were recorded, including 387 ischemic heart disease (IHD), 127 diabetes, and 459 stroke. Cox regression yielded adjusted hazard ratios (HRs) for CMDs associated with levels of 15:0. These results were further meta-analyzed with 33 additional prospective studies, involving 112,193 participants.

Results: OCFAs were significantly correlated with intakes of dairy products, wheat and coarse grains, and fish/seafood in the CKB. Both 15:0 and 17:0 were inversely associated with incident IHD, with adjusted HRs of 0.72 (95% CI 0.59-0.89) and 0.69 (0.56-0.86) for top vs. bottom tertile, respectively. Levels of 17:0 were also inversely associated with incident diabetes (0.41 [0.27-0.62]) and total CMDs (0.85 [0.74-0.97]). In the updated meta-analysis, both 15:0 and 17:0 levels showed inverse associations with diabetes, with pooled relative risks of 0.74 (0.68-0.80) and 0.65 (0.61-0.71) per 10th-90th percentile range, respectively. 17:0 was also inversely associated with incident IHD (0.87 [0.77-0.97]).

Conclusions: Our findings supported favorable associations between OCFAs and CMDs among populations with varied dietary sources and intake levels, which merits future intervention studies.