Cardiologists respond
ASCEND’s two designated discussants, both cardiologists, took a more positive view of the results than Dr. Armitage, who isn’t a cardiologist.
Sigrun Halvorsen, MD, professor of cardiology at the University of Oslo, noted that most ASCEND participants were at relatively low cardiovascular risk, with an event rate of about 1.3% per year. She indicated that she’d like to see more data on higher-risk individuals before excluding any role for aspirin in primary cardiovascular prevention in patients with diabetes.
“Serious vascular events and bleeding are not necessarily equally weighted,” she added. “Most major bleeds in ASCEND were GI bleeds, and these can be largely prevented by PPIs [proton pump inhibitors], in contrast to death and stroke, which are irreversible events.”
“I think this study could be interpreted more favorably,” agreed Christopher P. Cannon, MD, professor of medicine at Harvard Medical School, Boston. “Bleeds are reversible, but MIs and whatnot are not.”
Fish oil flounders in ASCEND
Louise Bowman, MD, also at the University of Oxford, presented the ASCEND fish oil findings. Over an average of 7.4 years, omega-3 fatty acid supplementation had no effect on the rate of serious vascular events, no effect on cancer, no impact on all-cause or cause-specific mortality, and raised no safety issues in patients with diabetes. She argued that current guidelines recommending fish oil supplements for cardiovascular prevention should be reconsidered.
“Certainly there doesn’t seem to be any justification for the use of this dose of omega-3 fatty acids – 1 g/day – for the prevention of cardiovascular disease,” Dr. Bowman said.
However, Dr. Cannon saw a sliver of hope within the ASCEND findings. One component of the serious vascular event composite endpoint – vascular death – occurred in 2.4% of the fish oil group and 2.9% of placebo-treated controls, for a statistically significant 19% relative risk reduction. It could be a fluke, given that none of the other vascular endpoints followed suit. But physicians and patients won’t have to wait long to find out. Another randomized trial of low-dose fish oil supplements for primary cardiovascular prevention – the nearly 26,000-patient VITAL trial – is due to report later in 2018.
In addition, two major, randomized trials of higher-dose fish oil supplementation for secondary prevention are ongoing. The roughly 8,000-patient REDUCE-IT trial is expected to report results later this year, and the STRENGTH trial, featuring more than 13,000 patients, should be completed in 2020. Both studies are heavily loaded with diabetes patients, Dr. Cannon noted.
Simultaneous with presentation of the ASCEND results at the ESC congress, the study was published online at the New England Journal of Medicine website (doi: 10.1056/NEJMoa1804988 and doi: 10.1056/NEJMoa1804989).
The ASCEND study was funded by the British Heart Foundation and the U.K. Medical Research Council with support provided by Abbott Laboratories, Bayer, Mylan, and Solvay. Dr. Armitage and Dr. Bowman reported receiving research grants from the Medicines Company, Bayer, and Mylan. Dr. Halvorsen reported no financial conflicts. Dr. Cannon reported serving as a consultant to roughly a dozen pharmaceutical companies, including the Amarin Corporation, which markets a fish oil supplement and sponsored the REDUCE-IT trial.