Diabetic benefit: EPA found to reduce cardiovascular risk in patients – meta analysis

This was based on a data analysis on eight randomized controlled trials undertaken on omega-3 fatty acids and cardiovascular outcomes in diabetic patients, involving 57,754 participants.

It elicited that omega-3 fatty acids supplementation in general had significantly reduced cardiovascular incidences in patients with diabetes (p = 0.0009). Notably, the risk was reduced even more when the patients were supplemented with EPA alone, than the combination of EPA and DHA (p = 0.0001).

The study was funded by the National Natural Science Foundation of China, the Department of Science and Technology of Sichuan Province, the Health Commission of Sichuan Province, and the Luzhou-Southwest Medical University cooperation project.

The researchers had uncovered emerging evidence that consuming omega-3 fatty acids improved some risk factors associated with cardiovascular diseases:

“A recent meta-analysis showed that ω-3 supplementation significantly reduced cardiometabolic biomarkers, such as LDL, very LDL, and TGs in patients with type 2 diabetes. ​

“A recent systematic review of​ clinical trials has shown that supplementation with ω-3 FAs reduces advanced glycation end products, which are associated with increased cardiovascular events in patients with type 2 diabetes. Moreover, ω-3 FAs have protective effects on pathophysiologic processes, such as inflammation, and endothelial dysfunction, in diabetes.”​

“An RCT by Tousoulis et al.​ showed that ω-3 FAs improved endothelial function and arterial stiffness in patients with metabolic syndrome and had anti-inflammatory effects. In addition, ω-3 FAs regulate the function of T cells and produce the antithrombotic metabolites thromboxane A3, prostacyclin, and specialized proresolving lipid mediators, such as resolvins, maresins, and protectins, which promote tissue repair and inflammation, and play an important role in the inflammatory mechanisms of atherosclerosis.”​

Investigating the specific effects caused by DHA and EPA, it has been shown that DHA increases LDL, also known as “bad” cholesterol, while EPA does the opposite. EPA also helps to enhance HDL in the body.

Safety to be considered​

Researchers warranted the need to consider the safety of omega-3 fatty acids despite its proven benefits.

Some previous studies demonstrated that its supplementation may increase the risk of atrial fibrillation – an abnormal heartbeat condition – although the results were not significant:

“The Omega-3 Fatty Acids in the Elderly with Myocardial Infarction (OMEMI) trial also reported that ω-3 FA supplements may be associated with a nonsignificant increased risk of atrial fibrillation in older patients with diabetes who have had a MI. ​

“A​ recent meta-analysis showed that supplementation with ω-3 FAs was significantly associated with an increased risk of atrial fibrillation, and the risk appeared to be increased at doses >1g/d. Because the benefits of ω-3 FA supplementation also appear to be dose dependent, the risks associated with atrial fibrillation should be balanced against the benefits of CVD.”​

Limitations of the study include different inclusion criteria used in the studies, type of diabetes was not indicated in many studies, lack of Asian representation among participants, and inconclusive evidence to clarify whether EPA alone is more effective than with the DHA combination.

“Omega-3 FA supplementation is an effective strategy to prevent cardiovascular outcomes in patients with diabetes. EPA alone was more effective than the combined supplementation of DHA and EPA. ​

“However, the effect of dose cannot yet be ruled out, and larger trials controlling for dose and other variables are needed to confirm this. ​

“Moreover, the safety of ω-3 FA supplements should be considered in their clinical applications. An increased risk of atrial fibrillation with ω-3 FA supplementation in patients with diabetes cannot be ruled out at this time, and this may have clinical implications that need to be verified in larger, comparative-dose clinical trials,” ​the paper concluded.

Source: American Society for Nutrition​

“Effect of Omega-3 Polyunsaturated Fatty Acids on Cardiovascular Outcomes in Patients with Diabetes: A Meta-analysis of Randomized Controlled Trials”

https://doi.org/10.1016/j.advnut.2023.04.009​

Authors: Huang, L., et al.​