Observational Studies of Treatment Effectiveness: Some Cautions
Authors: Andreas Laupacis, Muhammad Mamdani
Journal: Annals of Internal Medicine (2004)

Editorials1 June 2004Observational Studies of Treatment Effectiveness: Some CautionsAndreas Laupacis, MD, MSc and Muhammad Mamdani, PharmD, MA, MPHAndreas Laupacis, MD, MScFrom Institute for Clinical Evaluative Sciences, Toronto, Ontario M4N 3M5, Canada. and Muhammad Mamdani, PharmD, MA, MPHFrom Institute for Clinical Evaluative Sciences, Toronto, Ontario M4N 3M5, Canada.Author, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-140-11-200406010-00014 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail The last decade has seen an extraordinary proliferation of evidence that statins decrease mortality in patients who have, or are at risk for developing, cardiovascular disease (1, 2). The benefits extend to high-risk patients with normal cholesterol levels (2) and have led some to suggest that all individuals older than 55 years of age should receive statins as part of a "polypill" (3). In this issue, Spencer and colleagues (4) add to the evidence in favor of statins. They conclude that statin users with an acute coronary syndrome are less likely to present with ST-segment elevation or myocardial infarction than ...References1. LaRosa JC, He J, Vupputuri S. Effect of statins on risk of coronary disease: a meta-analysis of randomized, controlled trials. JAMA. 1999;282:2340-6. [PMID: 10612322] CrossrefMedlineGoogle Scholar2. MRC/BHF Heart Protection Study of cholesterol lowering with simvastatin in 20,536 high-risk individuals: a randomised placebo-controlled trial. Lancet. 2002;360:7-22. [PMID: 12114036] CrossrefMedlineGoogle Scholar3. Wald NJ, Law MR. A strategy to reduce cardiovascular disease by more than 80%. BMJ. 2003;326:1419. [PMID: 12829553] CrossrefMedlineGoogle Scholar4. Spencer FA, Allegrone J, Goldberg RJ, Gore JM, Fox KA, Granger CB, et al . Association of statin therapy with outcomes of acute coronary syndromes: The GRACE Study. Ann Intern Med. 2004;140:857-66. LinkGoogle Scholar5. Rossouw JE, Anderson GL, Prentice RL, LaCroix AZ, Kooperberg C, Stefanick ML, et al . Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results From the Women's Health Initiative randomized, controlled trial. JAMA. 2002;288:321-33. [PMID: 12117397] CrossrefMedlineGoogle Scholar6. Grady D, Herrington D, Bittner V, Blumenthal R, Davidson M, Hlatky M, et al . Cardiovascular disease outcomes during 6.8 years of hormone therapy: Heart and Estrogen/Progestin Replacement Study follow-up (HERS II). JAMA. 2002;288:49-57. CrossrefMedlineGoogle Scholar7. Schwartz GG, Olsson AG, Ezekowitz MD, Ganz P, Oliver MF, Waters D, et al . Effects of atorvastatin on early recurrent ischemic events in acute coronary syndromes: the MIRACL study: a randomized, controlled trial. JAMA. 2001;285:1711-8. [PMID: 11277825] CrossrefMedlineGoogle Scholar8. Glesby MJ, Hoover DR. Survivor treatment selection bias in observational studies: examples from the AIDS literature. Ann Intern Med. 1996;124:999-1005. [PMID: 8624068] LinkGoogle Scholar9. Redelmeier DA, Tan SH, Booth GL. The treatment of unrelated disorders in patients with chronic medical diseases. N Engl J Med. 1998;338:1516-20. [PMID: 9593791] CrossrefMedlineGoogle Scholar10. Rosenbaum PR, Rubin DB. The central role of the propensity score in observational studies for causal effects. Biometrika. 1983;70:41-55. CrossrefGoogle Scholar11. Juurlink DN, Mamdani M, Kopp A, Laupacis A, Redelmeier DA. Drug-drug interactions among elderly patients hospitalized for drug toxicity. JAMA. 2003;289:1652-8. [PMID: 12672733] CrossrefMedlineGoogle Scholar12. Mamdani M, Juurlink DN, Kopp A, Naglie G, Austin PC, Laupacis A. Gastrointestinal bleeding following the introduction of COX 2 inhibitors: an ecological study. BMJ. 2004; [In press]. Google Scholar13. Walter DH. Insights into early and rapid effects of statin therapy after coronary interventions. Curr Pharm Des. 2004;10:369-73. [PMID: 14965198] CrossrefMedlineGoogle Scholar14. Newby LK, Kristinsson A, Bhapkar MV, Aylward PE, Dimas AP, Klein WW, et al . Early statin initiation and outcomes in patients with acute coronary syndromes. JAMA. 2002;287:3087-95. [PMID: 12069671] CrossrefMedlineGoogle Scholar Author, Article, and Disclosure InformationAuthors: Andreas Laupacis, MD, MSc; Muhammad Mamdani, PharmD, MA, MPHAffiliations: From Institute for Clinical Evaluative Sciences, Toronto, Ontario M4N 3M5, Canada.Disclosures: None disclosed.Corresponding Author: Andreas Laupacis, MD, MSc, FRCPC, Institute for Clinical Evaluative Sciences, 2075 Bayview Avenue–G106, Toronto, Ontario M4N 3M5, Canada; e-mail, [email protected]on.ca.Current Author Addresses: Drs. Laupacis and Mamdani: Institute for Clinical Evaluative Sciences, 2075 Bayview Avenue–G106, Toronto, Ontario M4N 3M5, Canada. PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetailsSee AlsoAssociation of Statin Therapy with Outcomes of Acute Coronary Syndromes: The GRACE Study Frederick A. Spencer , Jeanna Allegrone , Robert J. Goldberg , Joel M. Gore , Keith A.A. Fox , Christopher B. Granger , Rajendra H. 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The Global Registry of Acute Coronary EventsTreating Patients With Acute Coronary Syndromes With Aggressive Antiplatelet Therapy (from the Global Registry of Acute Coronary Events)Improved Clinical Outcomes Associated With Metformin in Patients With Diabetes and Heart FailureBehandlung von Entzündungen im Bereich der oberen Atemwege – Vergleich eines homöopathischen Komplexpräparates mit XylometazolinDe betrouwbaarheid van observationeel onderzoek 1 June 2004Volume 140, Issue 11Page: 923-924KeywordsAcute coronary syndromeMortalityMyocardial infarctionObservational studiesOdds ratioRandomized trialsRelative riskStatinsSurvival analysisTreatment guidelines ePublished: 1 June 2004 Issue Published: 1 June 2004 Copyright & PermissionsCopyright © 2004 by American College of Physicians. All Rights Reserved.PDF downloadLoading ...