Table 1.

PICO characteristics of included studies

Study	Year	Patients (n)	Dose of EPA/DHA (mg)	Population	Intervention	Comparator	Outcome
DOIT18	2010	563	1150/800	Patients between 64 and 74-years-old, 74% of them without cardiovascular diseases	PUFAs	Placebo	All causes of mortality and cardiovascular disease
ARED-S19	2014	4203	650/350	Individuals between 50 and 85-years- old, with intermediate or advanced age-related macular degeneration and with stable, existing CVD	PUFAs or lutein + zeaxanthin	Combination of the two, or matching placebos	Myocardial infarction, stroke and cardiovascular death
SU-FOL-OM320	2010	2501	400/200	Patients with a history of myocardial infarction, unstable angina or ischaemic stroke	PUFAs	Vitamins or placebo	First major cardivascular events and cardiovascular death
Alpha Omega21	2010	4837	226/150	Men and women, 60 to 80 years of age, who had had a clinically diagnosed myocardial infarction up to 10 years before randomisation	PUFAs	Margarine	Major cardiovascular events, which comprised fatal and nonfatal cardiovascular disease and the cardiac interventions PCI and CABG
OMEGA22	2010	3818	460/380	Patients with a minimum age of 18 years who were admitted to hospital for acute STEMI or non-STEMI	PUFAs	Olive oil	Sudden cardiac death
R&P23	2013	12 505	500/500	Eligibility was based on one of the following: clinical evidence of atherosclerotic cardiovascular disease; multiple major cardiovascular risk factors; or other conditions putting the patient at high cardiovascular risk according to the GPs' judgement	PUFAs	Placebo	Death from cardiovascular causes
GISSI-HF24	2008	6975	850/950	Patients were men and women aged 18 years or older, with clinical evidence of heart failure of any cause that was classified according to the European Society of Cardiology	PUFAs	Placebo	Time to death or time to admission to hospital for cardiovascular reasons
ORIGIN25	2012	12 536	465/375	Patients with an age of at least 50 years; a diagnosis of diabetes, history of myocardial infarction, stroke or revascularisation; or angina, a ratio of urinary albumin to creatinine of more than 30 mg per gram	PUFAs	Placebo	Death from cardiovascular causes
GISSI-P26	1999	11 334	850/1700	Patients with recent (3 months) myocardial infarction	PUFAs and VIT E	Placebo	Death
ASCEND15	2018	15 480	1 g (n-3 fatty acids)	Patients with diabetes but without evidence of atherosclerotic cardiovascular disease	n-3 fatty acids	Placebo	Serious vascular event
VITAL16	2019	25 871	1 g (n-3 fatty acids)	Men aged≥50 and women aged≥55 with no history of cancer or cardiovascular disease	Vitamin D3 and n-3 fatty acids	Vitamin D3+placebo or placebo + n-3 fatty acids	Major cardiovascular events

CI, confidence interval; ctrl, controls; ev, events; PUFAs, polyunsaturated fatty acids.