The Periodical Second Issue, November 2002

 

 

Editors Note SAGAS Objectives SAGAS News Stroke Risk Factors: An Overview
A Need For A World Stroke Federation International Article Review The Periodical Quiz The Periodical Case

Editor's Note

IS REDUCTION OF BLOOD PRESSURE  BENEFICIAL TO PATIENTS WITH STROKE?

This is the second issue of the SAGAS periodical. In the first issue we presented some epidemiological data on stroke. At early stages of our meetings we agreed that risk factors in stroke should be addressed early in the activities of SAGAS;  notably, prevention strategies for recurrent stroke. These strategies are cost-effective because high-risk individuals are already identified and because a relatively small effort can make a large impact on outcome. At least 15% of survivors have a second stroke during the subsequent five years, and one quarter of these is fatal within four weeks [1]. The results of numerous studies show that hypertension, systolic more than diastolic [2,3], is a powerful and independent risk factor for all strokes: haemorrhagic, ischaemic and embolic, and that lowering blood pressure greatly diminishes the risk factor for cardiovascular disease. Among patients with a history of stroke there is a steep, continuous relationship between any level of blood pressure and the subsequent risk for stroke [4].    Risk for recurrent stroke increases by 28% for every of 10 mm Hg increment in systolic blood pressure between 130 and 160 mm Hg [5].More than 50% of survivors of stroke or myocardial infarction with documented hypertension, the blood pressure was not controlled [6].

Blood pressure and stroke should be addressed from several perspectives:  primary stroke prevention, secondary stroke prevention and acute stroke prevention. Blood pressure therapy is effective for primary stroke prevention. The Heart Outcome Prevention Evaluation (HOPE) study randomized patients at risk for myocardial infarction or stroke to Ramipril (an ACE inhibitor) or placebo [7]. Treatment was associated with 38% relative reduction in risk for ischaemic stroke and 28% for haemorrhagic stroke. A recent study found that blood pressure of 130 to 139 mm Hg systolic or 85 to 89 mm Hg diastolic conveyed an adjusted 2.5-fold increased risk of cardiovascular disease in men [2].

The result of the recently reported Peridopril Protection Against Recurrent Stroke Study (PROGRESS) [8] is perceived as a call for action. In this prospective study, more than 6000 patients who had stroke or TIA within the previous 5 years were randomized to either placebo of active treatment (Perindropil or Indapamide). This treatment was given in addition to pre-existing therapies, such as aspirin, antiplatelet agents, other anti-hypertensives and lipid-lowering agents. Because the trial was designed to produce additional reduction in blood pressure in each patient, current anti-hypertensive drugs (except ACE inhibitors or diuretics) were continued. Approximately 50% of all participants were considered normotensive at randomization. Blood pressure was lowered by an average of 9 mm Hg systolic and 4 mm Hg diastolic in the active treatment group, resulting an a 28% risk reduction for major stroke in all participants (95% CI 17-30%). This reduction extended to all forms of stroke and to patients with and without hypertension. In addition, reduction in dementia and cognitive dysfunction was significant (risk reduction 34%, and 95%, CI 3-55%), and there was no independent side effects of antihypertension therapy. There was only 1% withdrawal from the active treatment group for hypotension, compared with the placebo group. The PROGRESS data indicate that there was the same benefit to patients who started treatment early after stroke (1-2 months) as to those who started later.

In essence, results of the PROGRESS study indicate that regardless of what the patientsí blood pressure was at the time of the stroke, or how it was treated, Perindropil and Indapamide therapy will be beneficial. The unequivocal finding of the PROGRESS trial challenges the therapeutic nihilism regarding blood pressure in the post-stroke patients and mandates that all physicians actively assess and treat high blood pressure [9].

So, with the findings of this study, the benchmark of our knowledge of secondary stroke prevention has changed. We must face this challenge and integrate this new knowledge in the daily treatment of patients with stroke.

 

SAEED BOHLEGA, FRCPC, FRCP(Edin)

 

References

  1. Hankey GJ, Jamrozik K, Broadhurst RJ, et al.  Long-term risk of first recurrent stroke in the Perth Community Stroke Study.  Stroke 1998; 29: 2491-2500

  2.  Kannel WB, Wolf PA, McGee DL, et al.  Systolic blood pressure, arterial rigidity and risk of stroke.  The Framingham Study.  JAMA 1981: 245: 1225-1229

  3. SHEP Co-operative Research Group. Prevention of stroke by antihypertensive drug treatment in older persons with isolated systolic hypertension.  JAMA 1991; 265: 3255-3264

  4. Rodger SA, MacMahon S, Gamble G.  Blood pressure and risk of stroke in patients with cerebrovascular disease.  The United Kingdom Transient Ischaemic Attack Collaboration Group.  BMJ 1996; 313: 147

  5. Farrell B, Godwin J, Richards S.  The United Kingdom transient ischaemic attack aspirin trial, final results.  J Neurol Neurosurg Psychiatry 1991; 56: 1044-1054

  6. Qureshi AI, Suri MF, Guterman LR.  Ineffective secondary prevention in survivor of cardiovascular event in the US population.  Arch Intern Med 2001; 161: 1621-1628

  7. The Heart Outcome Prevention Evaluation Study Investigators.  Effects of an angiotensin converting enzyme inhibitor, ramipril, on cardiovascular events in high risk patients.  N Engl J Med 2000; 342: 145-153

  8. PROGRESS Collaborative Group.  Randomised trial of a perindopril-based blood pressure lowering regime among 6105 individuals with previous stroke.  Lancet 2001; 358: 1033-1034

  9. Messerli F, Hanlay D, Gorelick P.  Blood pressure control in stroke patients.  Neurology 2002; 59: 23-25