Table 4

Absolute reduction in myocardial infarctions by aspirin treatment of 100 persons for five years, and NNT, assuming relative risk reduction of 30%; and benefit net of bleeding complications of different severity

Myocardial infarcts preventedCHD event risk
MI prevNNTMI prevNNTMI prevNNT
Net of cerebral haemorrhage (0.19)4-150 0.561791.31762.0649
Net of major bleeds (0.17)4-150 0.392561.14881.8953
Net of non-minor bleeds (0.76)4-150 −0.20(500)4-151 0.551821.3077
  • 4-150 Absolute risk of bleeding complications in 100 persons per five years, assumed constant and independent of CHD event risk.

  • 4-151 Number treated for five years to harm one person (NNTH).

  • MI prev, myocardial infarcts prevented; NNT, number needed to treat for five years.