Acetylsalicylic acid ( ASA ) did not reduce stroke or ' all cardiovascular events ' compared to placebo in primary prevention patients with elevated blood pressure and no prior cardiovascular disease .
Antiplatelet therapy with ASA for primary prevention in patients with elevated blood pressure provides a benefit , reduction in myocardial infa rct ion , which is negated by a harm of similar magnitude , increase in major haemorrhage .
The benefit of antiplatelet therapy for secondary prevention in patients with elevated blood pressure is many times greater than the harm .
Benefit has not been demonstrated for warfarin therapy alone or in combination with aspirin in patients with elevated blood pressure .
BACKGROUND Elevated systemic blood pressure results in high intravascular pressure but the main complications , coronary heart disease ( CHD ) , ischaemic strokes and peripheral vascular disease ( PVD ) , are related to thrombosis rather than haemorrhage .
Some complications related to elevated blood pressure , heart failure or atrial fibrillation , are themselves associated with stroke and thromboembolism .
Therefore it is important to investigate if antithrombotic therapy may be useful in preventing thrombosis-related complications in patients with elevated blood pressure .
OBJECTIVES To conduct a systematic review of the role of antiplatelet therapy and anticoagulation in patients with high blood pressure , including those with elevations in both systolic and diastolic blood pressure , isolated elevations of either systolic or diastolic blood pressure , to address the following hypotheses : ( i ) antiplatelet agents reduce total deaths and /or major thrombotic events when compared to placebo or other active treatment ; and ( ii ) oral anticoagulants reduce total deaths and /or major thromboembolic events when compared to placebo or other active treatment .
Ticlopidine , clopidogrel and newer antiplatelet agents such as prasugrel and ticagrelor have not been sufficiently evaluated in patients with high blood pressure .
Comparative Safety and Tolerability of Clopidogrel and Aspirin
Objective The objective of this study was to provide a comprehensive comparison of the long term safety and tolerability of clopidogrel , a new adenosine diphosphate ( ADP ) receptor antagonist that inhibits platelet activation induced by ADP , and aspirin ( acetylsalicylic acid ) . Patients and Methods The study population comprised 19 185 patients with symptomatic atherosclerosis manifested as recent ischaemic stroke , recent myocardial infa rct ion or symptomatic peripheral arterial disease . Patients were r and omised to receive  clopidogrel 75 mg/day or aspirin 325 mg/day  for a minimum of 1 year and a maximum of 3 years . Results Compared with aspirin , clopidogrel reduced the combined risk of ischaemic stroke , myocardial infa rct ion or vascular death by 8.7 % ( p = 0.043 ) . The incidence of early permanent discontinuations of the study drug due to adverse events was almost identical in both treatment groups ( 11.94 % for clopidogrel vs 11.92 % for aspirin ) . Reported neutropenia was similar in the clopidogrel and aspirin groups ( 0.10 vs 0.17 % , respectively ) with corresponding rates ( 0.05 vs 0.04 % , respectively ) for severe neutropenia . Thrombocytopenia was identical in the clopidogrel and aspirin groups ( 0.26 % ) , with the rates of severe thrombocytopenia being 0.19 vs 0.10 % , respectively . None of these observed differences was statistically significant . The overall incidence of haemorrhagic events did not differ statistically significantly between treatment groups ( 9.27 % for clopidogrel vs 9.28 % for aspirin ; p = 0.98 ) . There was a trend towards a lower incidence of intracranial haemorrhage in the clopidogrel group ( 0.31 % ) compared with the aspirin group ( 0.42 % ) . Any reported gastrointestinal haemorrhage was significantly less frequent with clopidogrel ( 1.99 % ) than with aspirin ( 2.66 % ) [ p < 0.002 ] . The corresponding data for severe gastrointestinal bleeding were 0.49 vs 0.71 % ; p < 0.05 . Overall , there were significantly fewer gastrointestinal adverse events with clopidogrel than with aspirin ( 27.1 vs 29.8 % ; p < 0.001 ) , with less abdominal pain , dyspepsia , constipation , or peptic , gastric , or duodenal ulceration with clopidogrel .  Diarrhoea was significantly more common in the clopidogrel group ( 4.46 vs 3.36 % ; p < 0.001 ) , although the incidence of severe diarrhoea ( 0.23 vs 0.11 % ) was low and was not significantly different between groups . There were significantly more patients with rash in the clopidogrel group ( 6.0 % ) compared with the aspirin group ( 4.6 % ) [ p < 0.001 ] . However , these events were generally mild and transient in nature . Conclusion Given the favourable benefit/risk ratio , clopidogrel represents a clinical ly important advance in the treatment of patients with manifest atherosclerotic disease
Acetylsalicylic acid ( ASA ) did not reduce stroke or ' all cardiovascular events ' compared to placebo in primary prevention patients with elevated blood pressure and no prior cardiovascular disease .
Antiplatelet therapy with ASA for primary prevention in patients with elevated blood pressure provides a benefit , reduction in myocardial infa rct ion , which is negated by a harm of similar magnitude , increase in major haemorrhage .
The benefit of antiplatelet therapy for secondary prevention in patients with elevated blood pressure is many times greater than the harm .
Benefit has not been demonstrated for warfarin therapy alone or in combination with aspirin in patients with elevated blood pressure .
BACKGROUND Elevated systemic blood pressure results in high intravascular pressure but the main complications , coronary heart disease ( CHD ) , ischaemic strokes and peripheral vascular disease ( PVD ) , are related to thrombosis rather than haemorrhage .
Some complications related to elevated blood pressure , heart failure or atrial fibrillation , are themselves associated with stroke and thromboembolism .
Therefore it is important to investigate if antithrombotic therapy may be useful in preventing thrombosis-related complications in patients with elevated blood pressure .
OBJECTIVES To conduct a systematic review of the role of antiplatelet therapy and anticoagulation in patients with high blood pressure , including those with elevations in both systolic and diastolic blood pressure , isolated elevations of either systolic or diastolic blood pressure , to address the following hypotheses : ( i ) antiplatelet agents reduce total deaths and /or major thrombotic events when compared to placebo or other active treatment ; and ( ii ) oral anticoagulants reduce total deaths and /or major thromboembolic events when compared to placebo or other active treatment .
Ticlopidine , clopidogrel and newer antiplatelet agents such as prasugrel and ticagrelor have not been sufficiently evaluated in patients with high blood pressure .