Treatment with omega-3 polyunsaturated fatty acids does not improve endothelial function in patients with type 2 diabetes and very high cardiovascular risk: A randomized, double-blind, placebo-controlled study (Omega-FMD)

But do you want it for all these other benefits? I have 62 posts on Omega-3s with lots of benefits. Ask your doctor for an analysis and whether this research was trying to fix advanced atherosclerotic cardiovascular disease and that is the reason it failed. Would it help less advanced cases? 
https://www.mdlinx.com/internal-medicine/medical-news-article/2018/03/02/cardiovascular-disease-atherosclerosis-type-2-diabetes/7505276/?

Atherosclerosis — | March 02, 2018

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Siniarski A, et al. - Researchers determined the effect of high-dose omega-3 polyunsaturated fatty acid (n-3 PUFA) treatment on endothelial function in patients with type 2 diabetes (T2D) and established atherosclerotic cardiovascular disease (ASCVD). No improvement was seen in the endothelial function indices after high-dose n-3 PUFA treatment for 3 months in very high-risk patients with ASCVD and T2D.

• See Also: Duration of diabetes and prediabetes during adulthood and subclinical atherosclerosis and cardiac dysfunction in middle age: The CARDIA study

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