Is the combination of aspirin and clopidogrel always better than aspirin alone? Or will it be too much of a good thing?
Confucious was probably the person who once said, “All thingsgood not cheap, all things cheap not good.
”Aspirin is one medicine that tests this aphorism because it isboth cheap and good. Enough evidence exists to show thatlow dose aspirin helps to reduce cardiovascular risk in thosewith coronary heart disease, ischaemic strokes and otherswith established atherosclerotic vascular disease.
In 1998 the results of the Second International Study of InfarctSurvival (ISIS-2)1 were reported. Here aspirin was shown tobe beneficial in the management of patients after an acutemyocardial infarction. This benefit was in addition to the benefitof thrombolysis.
Aspirin is also useful for primary prevention in selected patientsthrough its ability to reduce the risk of heart attacks and strokesin people without any overt cardiovascular disease. ThePhysicians Health Study2 showed that healthy males,particularly those fifty years of age and older, taking 325mg ofaspirin every other day could reduce their risk of myocardialinfarctions significantly. However there is a tendency forincreased gastrointestinal bleeding and haemorrhagic strokesbecause of aspirin and hence such prescriptions need to beindividualised. The Women’s Health Study3 showed thathealthy women who were forty-five years of age and olderand who took 100mg of aspirin every other day had asignificantly lower risk of strokes. (copied from article)
Baigent C, Collins R, Appleby P, et al. ISIS-2: 10 year survival among patients with suspected acute myocardial infarction in randomised comparison of intravenous streptokinase, oral aspirin, both, or neither. The ISIS-2 (Second International Study of Infarct Survival) Collaborative Group. BMJ. 1998;316(7141):1337-43.
Final report on the aspirin component of the ongoing Physicians’ Health Study. Steering Committee of the Physicians’ Health Study Research Group. N Engl J Med. 1989;321(3):129-5.
Ridker PM, Cook NR, Lee IM, et al. A randomized trial of lowdose aspirin in the primary prevention of cardiovascular disease in women. N Engl J Med. 2005;352(13):1293-1304.
A randomised, blinded, trial of clopidogrel versus aspirin in patients at risk of ischaemic events (CAPRIE). CAPRIE Steering Committee. Lancet. 1996;348(9038):1329-39.
Yusuf S, Zhao F, Mehta SR, et al. Effects of clopidogrel in addition to aspirin in patients with acute coronary syndromes without ST-segment elevation. N Engl J Med. 2001;345(7):494-502.
Sabatine MS, Cannon CP, Gibson CM, et al. Addition of clopidogrel to aspirin and fibrinolytic therapy for myocardial infarction with ST-segment elevation. N Engl J Med. 2005;352(12):1179-89.
Chen ZM, Jiang LX, Chen YP, et al. Addition of clopidogrel to aspirin in 45,852 patients with acute myocardial infarction: randomised placebo-controlled trial. Lancet. 2005;366(9497):1607-21.
Mehta SR, Yusuf S, Peters RJ, et al. Effects of pretreatment with clopidogrel and aspirin followed by long-term therapy in patients undergoing percutaneous coronary intervention: the PCI-CURE study. Lancet. 2001;358(9281):527-33.
Steinhubl SR, Berger PB, Mann JT, et al. Early and sustained dual oral antiplatelet therapy following percutaneous coronary intervention: a randomized controlled trial. JAMA. 2002;288(19):2411-20.
Bhatt DL, Fox KAA, Hacke W, et al. Clopidogrel and aspirin versus aspirin alone for the prevention of atherothrombotic events. N Engl J Med. 2006;354(16):1706-17.
Keller TT, Squizzato A, Middeldorp S. Clopidogrel plus aspirin versus aspirin alone for preventing cardiovascular disease. Cochrane Database Syst Rev. 2007, Issue 3. Art. No.: CD005158. DOI: 10.1002/14651858.CD005158.pub2.
Wang TH, Bhatt DL, Fox KA, et al. An analysis of mortality rates with dual-antiplatelet therapy in the primary prevention population of the CHARISMA trial. Eur Heart J. 2007;28(18):2200-7.