Myocardial infarction: increasing fish intake reduced mortality.

Clinical bottom line (level 1b)

  1. Patients with a myocardial infarction who received advice to eat more fish were less likely to die (NNT = 28 at years) . There was no clear effect on non-fatal myocardial infarction.
  2. There was no clear effect on death or myocardial infarction from advising patients to reduce fat intake or increase fibre intake.
Burr et al: Lancet 1989; 2 (8666): 757-761
Expires March 2003

The study

Unblinded ?concealed randomised trial with intention-to-treat
Setting: 21 acute hospitals, UK

2033 patients (aged mean 57, 100% male) with a myocardial infarction

Excluded if
  • diabetes mellitus
  • awaiting cardiac surgery
  • already intending to eat one of the intervention diets
  • female
  • aged > 70


    • Note:
  • Patients were randomised factorially, so they could receive more than one of the interventions.


    • Control Group: (n = 1015, 1015 analysed): no advice
    Experimental Group: (n = 1018, 1018 analysed): fat advice: advised to reduce fat intake to < 30% of total energy and to increase polyunsaturated/saturated ratio to 1.0
    Experimental Group: (n = 1015, 1015 analysed): fish advice: advised to eat at least two weekly portions of fatty fish (mackerel, herring, kipper, pilchards, sardines, salmon or trout)
    Experimental Group: (n = 1017, 1017 analysed): fibre advice: advised to increased intake of cereal fibre to 18 g daily

    100% followed for 2 years
    Outcome notes:
    • death : fat advice
    • non-fatal myocardial infarction : fat advice
    • death : fish advice
    • non-fatal MI : fish advice
    • death : fibre advice
    • non-fatal MI : fibre advice

    The evidence

    fat advice
    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    death 2 years 113
    (11.1%)    		 111
    (10.9%)    		 2%
    (-25% to 24%)    		 0.23%
    (-2.49% to 2.95%)    		 440
    (NNT = 34 to infinity;
    NNH = 40 to infinity)
    non-fatal myocardial infarction 2 years 47
    (4.63%)    		 35
    (3.44%)    		 26%
    (-14% to 52%)    		 1.19%
    (-0.518% to 2.90%)    		 84
    (NNT = 34 to infinity;
    NNH = 190 to infinity)

    fish advice
    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    death 2 years 130
    (12.8%)    		 94
    (9.26%)    		 27%
    (7% to 44%)    		 3.51%
    (0.79% to 6.23%)    		 28
    (16 to 130)
    non-fatal MI 2 years 33
    (3.24%)    		 49
    (4.83%)    		 -49%
    (-130% to 3%)    		 -1.59%
    (-3.30% to 0.12%)    		 -63
    (NNT = 810 to infinity;
    NNH = 30 to infinity)

    fibre advice
    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    death 2 years 101
    (9.94%)    		 123
    (12.1%)    		 -22%
    (-56% to 5%)    		 -2.15%
    (-4.87% to 0.567%)    		 -46
    (NNT = 180 to infinity;
    NNH = 21 to infinity)
    non-fatal MI 2 years 41
    (4.04%)    		 41
    (4.03%)    		 0.0%
    (-53% to 53%)    		 0.00%
    (-1.71% to 1.71%)    		 25000
    (NNT = 58 to infinity;
    NNH = 59 to infinity)

    Citation

    1. Burr ML, Fehily AM, Gilbert JF, et al: Effects of changes in fat, fish, and fibre intakes on death and myocardial infarction: diet and reinfarction trial (DART). Lancet 1989; 2 (8666): 757-761
    Search Terms: myocardial near infarct* in Cochrane
    Contributor: Chris Ball and Clare Wotton, February 2000
    Reviewer:

    Clinical Question.
    Patient myocardial infarction
    Intervention or Exposure dietary advice
    Outcome death, myocardial infarction