The Appropriate Interpretation of Recent Clinical Trials -How to Read RCT in the Era of Advertizing-based Medicine-

Iwao Kuwajima

doi:10.5646/jksh.2011.17.1.1

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Kuwajima: The Appropriate Interpretation of Recent Clinical Trials -How to Read RCT in the Era of Advertizing-based Medicine-

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J Korean Soc Hypertens 2011;17(1):1-9.

Published online: 10 March 2011

DOI: https://doi.org/10.5646/jksh.2011.17.1.1

The Appropriate Interpretation of Recent Clinical Trials -How to Read RCT in the Era of Advertizing-based Medicine-

Iwao Kuwajima, MD

Division of Cardiology, Tokyo Metropolitan Geriatric Hospital, Tokyo, Japan

Correspondence to: Iwao Kuwajima, MD 주소: Division of Cardiology, Tokyo Metropolitan Geriatric Hospital, 35-2 Sakaecho, Itabashi-ku, Tokyo 173-0015, Japan Tel: +81-3-3964-1141, Fax: +81-3-3964-1982 E-mail: kuwajima@tmghig.jp

Received 14 February 201110 March 2011 Accepted 11 March 2011

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

ABSTRACT

Although evidence-based medicine (EBM) has changed medical therapy from experience- or experiment-based medicine to the modern science-based medicine, nowadays it seems to be used as a tool of advertizing strategy of industries. Clinical trial is a fundamental component of EBM and it costs very much and are mostly conducted by the financial support of pharmaceutical industries at a tremendous expense. If anticipated results for the sponsor were not shown in the trial, a “spin” has been used to mislead readers as if positive results for test drugs or devices were obtained by emphasizing subgroup analysis, or searching favorable endpoint by post-hoc analysis. Clinical trials on angiotensin receptor blocker (ARB) are continuing succession of defeat all over world except two Japanese clinical trials, JIKEI HEART and KYOTO HEART studies. However, in both trials, subjective soft endpoints, such as angina pectoris or congestive heart failure were used despite of prospective randomized, open labeled, blinded endpoint design. In the era of advertizing-based medicine, It is important to read clinical trial data with critical view points.

Keywords: Evidence-based medicine, Prospective randomized open labeled blinded endpoint, Randomized controlled trials, Post-hoc analyses, Angiotensin receptor blocker

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Fig. 1.

Proportion of trials significantly favoring newer treatments over standard of care.⁴⁾

Fig. 2.

Evaluation of Losartan in the Elderly Study II. Primary endpoint: All-cause mortality.¹⁰⁾

Fig. 3.

VThe Valsartan Antihypertensive Long-term Use Evaluation: hazard ratio of primary and secondary endpoints.¹⁰⁾

Fig. 4.

Hazard ratios (HR) for major endpoints in patients on valsartan or amlodipine based therapies. Events occurring after a baseline transiocated to the 6 months point of the trial (after adjustment designed to achieve BP control) in 5006 treament cohort pairs matched by SBP, age, sex and the presence or absence of prior coronary disease, stroke and diabetes.¹²⁾ CI, confidence interval.

Fig. 5.

KYOTO HEART study. Hazard ratio and 95%confidence intervals adjusted for sex, age, diabetes, smoking, dyslipidemia, and concomitant antihypertensive treatment.²¹⁾ ARB, angiotensin receptor blocker.

Fig. 6.

Any diabetes-related endpoints.²⁶⁾

Fig. 7.

ACE inhibitors in stable coronary artery disease. Comparison of outcomes in the PEACE and HOPE trials.²⁸⁾ ACE, angiotensin converting enzyme; HOPE, Heart Outcomes Prevention Evaluation; PEACE, Prevention of Events with Angiotensin-Converting Enzyme inhibition.

Table 1.

Changing therapy for coronary disease

Concomitant therapy (%)	HOPE (2000)	PEACE (2004)	ONTARGET (2008)	TRANSCEND (2008)
Statin	29	70	62	55
Antiplatelets	76	90	76	80
Beta blocker	39	60	58	58
Coronary revascularization	40	72	51	46

( ): year of reporting.

HOPE, Heart Outcomes Prevention Evaluation; PEACE, Prevention of Events with Angiotensin-Converting Enzyme inhibition; ONTARGET, The ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial; TRANSCEND, Telmisartan Randomized Assessment Study in ACE Intolerant Subjects with Cardiovascular Disease.

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