Previous studies have produced conflicting results regarding the effects of omega-3 on cardiovascular disease risk, but the serum omega-3 concentrations of the subjects involved in those studies was not always understood.
As such, researchers at the Peking University Hospital conducted a study to examine the link between serum omega-3 PUFA concentration and coronary artery disease.
Acidic advantage?
They recruited 460 Chinese in-patients who either had multiple cardiovascular risk factors or an established cardiovascular disease diagnosis.
The patients' serum omega-3 PUFAs — including docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) — were measured using liquid chromatography mass spectrometry.
Subsequently, the researchers observed that the patients who already had cardiovascular disease had lower serum concentrations of omega-3 PUFAs than those who had cardiovascular risk factors.
In addition, they wrote that a high concentration of serum DHA was "an independent protective factor of cardiovascular disease after adjustment for confounding factors", namely, age, gender, and co-morbidity conditions.
At the same time, alcohol consumption and proton pump inhibitor (PPI) use were linked to a reduction in serum ω-3 PUFA concentration, suggesting that lower alcohol intake and PPI use might help to raise the serum levels.
Restrictions and considerations
The researchers wrote that there were some restrictions involved in the study. As it was a cross-sectional design, it precluded them from "obtaining a definite conclusion on the cause-effect relationship between ω-3 PUFAs and cardiovascular disease".
Furthermore, the study being hospital-based meant they could not rule out the possibility of selection bias, and recalling and reporting bias could have affected the accuracy of their baseline ω-3 PUFA intake calculation.
This led them to state that longer-term and larger-scale studies were necessary to confirm their findings.
In conclusion, they wrote: "The current study suggests that high serum ω-3 PUFA concentration is associated with decreased cardiovascular disease proportion at a relatively younger age.
"Moreover, DHA may be an independent protective factor of cardiovascular disease. Additionally, serum ω-3 PUFA concentration may be reduced by alcohol intake and certain drugs like PPIs."
Source: Scientific Reports
https://doi.org/10.1038/s41598-018-19193-5
"Serum ω-3 Polyunsaturated Fatty Acids and Potential Infuence Factors in Elderly Patients with Multiple Cardiovascular Risk Factors"
Authors: Wenwen Liu, et al.