The PROGRESS trial three years later: time for a balanced report of effectivenessBMJ 2004; 329 doi: https://doi.org/10.1136/bmj.329.7472.968 (Published 21 October 2004) Cite this as: BMJ 2004;329:968
- Richard Wennberg (Richard.Wennberg@uhn.on.ca), associate professor1,
- Camilla Zimmermann, lecturer1
- 1 Department of Medicine, University of Toronto, University Health Network, Toronto, ON, Canada M5T 2S8
- Correspondence to: R Wennberg
Any doctor who keeps up to date with the stroke literature will be familiar with PROGRESS—the perindopril protection against recurrent stroke study,1 a clinical trial which had resulted, by February 2004, in more than 35 ancillary publications. The aim of the study was to “resolve clinical uncertainty about the efficacy and safety of routine blood-pressure-lowering therapy for individuals with a history of stroke or transient ischemic attack.”1 The trial found that blood pressure lowering was safe and effective, but three years after its publication, the optimal antihypertensive regimen for secondary stroke prevention remains unclear. The title of the study, together with its results as reported, may lead the unwary reader to conclude that perindopril used alone protects against recurrence of stroke. Although this was actually not a finding of PROGRESS, the study design and data presentation obfuscate this fact rather than making it clear.
Design of the trial
The PROGRESS trial had a “flexible” design, which meant that not all patients received the same antihypertensive regimen. Patients who had had a stroke or transient ischaemic attack in the previous five years were eligible. They were also required to have “no definite indication (such as heart failure) for treatment with an ACE inhibitor and no definite contraindication (such as previous intolerance) to such treatment.” The entry criteria did not include blood pressure, but treatment with agents other than angiotensin converting enzyme inhibitors was recommended to patients with uncontrolled hypertension before they entered the trial. Patients were then randomised, on a double …