Table 5.
Observed percentage reductions in coronary heart disease (CHD) events and stroke in single and combination drug treatment blood pressure difference trials compared with predicted reductions according to number of drugs, dose, pretreatment blood pressure, and age (60-69 years) (tables 3 and 4), adjusted for proportion of treated participants not taking their allocated tablets (25%)
| Category of drug trial† | No of trials* | Average No of drugs per participant | Mean dose (multiple of standard33) | Mean pretreatment blood pressure (mm Hg) | No of disease events | Percentage reduction in cardiovascular disease events | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CHD | Stroke | |||||||||||||
| Systolic | Diastolic | CHD | Stroke | Observed in trials (95% CI) | Predicted based on systolic and diastolic | Observed in trials (95% CI) | Predicted based on systolic and diastolic | |||||||
| Single | 65 | 1.0 | 1.7 | 140 | 81 | 9417 | 4712 | 15 (11 to 19) | 19 and 17 | 27 (20 to 34) | 25 and 25 | |||
| Combination | 8 | 2.0 | 1.2 | 160 | 91 | 394 | 708 | 25 (9 to 38) | 36 and 34 | 41 (31 to 50) | 45 and 48 | |||
*One trial was part single drug and part combined drug therapy,w118 hence numbers sum to 73 when there were 72 trials.
†In “single” drug trials the difference between intervention and control groups in average number of drugs taken per participant, taking account of “add-on” therapy in individual trials, was <1.5, in combination drug trials ≥1.5.