Study details: LRC (34)
Year: 1984
Main outcome: Nonfatal MI, CHD death
Cumulative event ratea: 8.1/9.8
I/C: (5.5/6.6)b
ARR: 1.7 (1.1)b
NNT for 5 years: (91)b
RRR (%): 19
(95% CI): (3-32)d
Study details: Helsinki (35)
Year: 1987
Main outcome: Nonfatal MI, CHD death
Cumulative event ratea: 2.73/4.14
I/C:
ARR: 1.41
NNT for 5 years: 71
RRR (%): 34
(95% CI): (8-53)
Study details: WOSCOPS (36)
Year: 1995
Main outcome: Nonfatal MI, CHD death
Cumulative event ratea: 5.5/7.9
I/C:
ARR: 2.4
NNT for 5 years: 42
RRR (%): 31
(95% CI): (17-43)
Study details: AFCAPS (37)
Year: 1998
Main outcome: Nonfatal MI, CHD death, unstable angina
Cumulative event ratea: 3.4/5.45
I/C: 1.65/2.9c
ARR: 2.05(1.25)c
NNT for 5 years: 49(80)c
RRR (%): 37
(95% CI): (21-50)d
[a]Event rates are cumulative incidence in percentages for the event over the study; I, intervention, C, control.
[b]Adjusted 5-year outcomes for LRC.
[c]Unstable angina excluded in results.
[d]CI for LRC was 90%.
[e]NNT for 5 years to prevent 1 CHD event.
*LRC, Lipids Research Council; HHS, Helsinki Heart Study; WOSCOPS, West of Scotland Coronary Prevention Study; AFCAPS, Air Force/Texas Coronary Atherosclerosis Prevention; MI, myocardial infarction; CHD, coronary heart disease; ARR, absolute risk reduction; NNT, numbers needed to treat; RRR, relative risk reduction; CI, confidence interval.