|Year : 2006 | Volume
| Issue : 2 | Page : 65-68
Clinical approach of evidence based therapy For cardiovascular disease
Mohammad A Bajubair1, N Jaber2, A Alnono2
1 Assistant professors, Faculty of Medicine and Health sciences, University of Sana'a, Yemen
2 Cardic Centre , Althawra Teaching Hospital, Sana'a, Yemen
|Date of Web Publication||17-Jun-2010|
Mohammad A Bajubair
Assistant professors, Faculty of Medicine and Health sciences, University of Sana'a
| Abstract|| |
Background: Evidence based drug therapy (EBT) is defined in a way that emphasizes the importance of outcomes and states, that a doctor makes his decisions according to the best available knowledge. EBT narrowly defines "evidence" for effective, ethical therapy as 'results' from double-blind research done with randomly controlled clinical trials (RCTs). Cardiovascular disease (CVD) and drug therapy is a rapidly changing field and one is always open to new evidence or evidence that may have been overlooked in the past. Not all doctors want or need to learn how to practice all five steps of EBT, indeed, most doctors consider themselves users of EBT. Clinical practice requires more stable data in the literature and especially in the teaching and training textbooks. Practicing EBT is an advance in drug therapy and is believed to help relieve contradiction and confusion of the therapy.
Objectives : Our aim was to explore the new clinical evidence in the treatment of CVD in clinical practice and the availability of RCTs in the textbooks and commonly used literature.
Methods : Cross-sectional interview survey of 20 physicians in the cardiac centre, Althawra teaching hospital, Sanaa, Yemen; to understand the drug use in regard to the EBT (clinically evidenced RCTs) or the mechanism of actions and experiences (non-clinical evidences) especially focusing on ischemic heart disease and heart failure. The five commonly used textbooks were studied for the availability of RCTs.
Results : In chronic ischemic heart diseases, ABC regimen (Aspirin, B-blockers, and angiotensin converting enzyme inhibitors, Captopril) as secondary prevention was selected by most of the physicians (70%), while nitrates put as first drug of choice for chronic ischemia more by general physicians (30%). In the treatment of congestive heart failure (CHF), digoxin (10%) was reported to be the first choice more by the newly graduated physicians. All new editions of the textbooks have included the RCTs as the basis for the therapy in clinical practice, especially in Braunwald Heart disease and Davidsons Medicine.
Conclusions : Results showed a need for a correlation between basic evidence and clinical evidence (EBT). Including the RCTs in the commonly used textbooks may help in the familiarity for searching new evidence and will help to relieve some of the confusion about clinical practice of therapy.
Keywords: evidence-based therapy, cardiovascular diseases
|How to cite this article:|
Bajubair MA, Jaber N, Alnono A. Clinical approach of evidence based therapy For cardiovascular disease. Heart Views 2006;7:65-8
| Introduction|| |
Initially, EBM mainly focused on determining the best research evidence relevant to a clinical problem or decision and applying that evidence to resolve the issue. More recently it has been defined as "the integration of best research evidence with clinical expertise and patient values". The earlier definition de-emphasized traditional determinants of clinical decisions, including physiological rationale and individual clinical experience  .
Commonly, EBM is defined in a positive and individualistic way that emphasizes the importance of outcomes and states, that a doctor makes decisions according to the best available knowledge, and that this knowledge is acquired by the best possible empirical scientific methods , .
Evidence based drug therapy (EBT) means integrating the best evidence, the individual characteristics of the patient, and individual clinical expertise, into a decision making process which leads to optimal drug therapy. This is a complex process that requires a detailed understanding of the evidence, including how the evidence was derived and an appreciation of the magnitude of the benefits and/or risks 
Sackett's definition of evidence based medicine is: The conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients. Its practice means integrating individual clinical expertise with best available external evidence from systematic research  .
This is limited to the best evidence, the randomized-controlled, double-blind clinical trial, or meta-analysis of randomized controlled trials, whenever possible. We try to focus on trials that measure the true goal of therapy (e.g. morbidity and mortality) and not surrogate markers (e.g. blood pressure).
The only available evidence may be based on surrogate endpoints, cohort studies, case control studies, or sub-group analyses of randomized controlled trials. Such forms of evidence are interesting and hypothesis generating, but are not conclusive. Questions of the efficacy of interventions usually mean that randomised controlled trials should be sought, while questions of risk usually mean that prospective cohort studies should be sought  . EBT narrowly defines "evidence" for effective, ethical therapy as "results" from randomly controlled clinical trials.
The mission of evidence-based practice is to optimise the chance that patients receive treatments that are most likely to enhance their health. The consequences of complete provider autonomy are that healthcare costs escalate with no clear connection to patient benefit. And, as we are seeing, when costs go up, employers are more likely to leave their employees uninsured. In other words, one consequence of provider autonomy is that the number of people with no healthcare increases and the average health of a community declines , .
However, several surveys have reached the conclusion that clinical decisions are rarely based on the best available evidence , . Cardiovascular disease and drug therapy is a rapidly changing field. The epidemiological view of EBT is that the clinical practice requires more stable data in the literature and especially in the teaching and training textbooks. Practicing EBT is an advance in the drug therapy and believed to help in relieving contradiction and confusion of the therapy.
Our aim was to explore the need to follow the new clinical evidence in the treatment of CVD in clinical practice and the availability of RCTs in the textbooks and commonly used literature.
| Methods|| |
Cross-sectional interview survey of 20 physicians in the cardiac centre, Althawra teaching hospital, Sanaa, Yemen; to understand the drug use in regard to the EBT (clinically evidenced, RCTs) or the mechanism of actions (non-clinical evidence) especially focusing on ischemic heart disease and heart failure. The five commonly used textbooks were studied for the availability of RCTs.
The questionnaire was completed by the investigating doctor to ensure that the participating doctors completed the questionnaire and understood the meaning and to ensure confidentiality and avoid missing responses for some items of the questionnaire.
| Results|| |
Personal professional characteristics were summarized in [Table 1].
Baseline knowledge of physicians and examples of EBM oriented drug therapy: three questions about some drug therapy examples have been answered differently by the participants [Table 2].
In chronic ischemic heart diseases, ABC regimen ,,,, (Aspirin, B-blockers, and angiotensin converting enzyme inhibitors, Captopril) as secondary prevention was selected by most of the physicians (70% ), while nitrates as first drug of choice for chronic ischemia were chosen more by general physicians (30%).
In the treatment of congestive heart failure (CHF), digoxin (10%), this may reflect the good familiarity for RCTs, this is also the case with spironolactone use (100 vs 10%). B-blocker use in CCF (40% vs 40%) is still unknown or unaccepted by many physicians.
| Textbooks and Literature Search for New Drugs|| |
The five commonly used textbooks were Braunwald Heart disease 14(70%), Topol Cardiovascular Diseases 14 (70%), Davidson's Medicine 8(40%), Harrison's Principles of Internal Medicine 8 (40%) and Oxford Medicine 4 (20%). In addition there is regular follow up of some internet connections as American Heart Association 8 (40%) and the European Heart Association 8 (40%).
All new editions of the textbooks have included the RCTs as the basis for the therapy in clinical practice, especially in Braunwald Heart disease  and Davidson's Medicine .
Davidson's Medicine  has many areas of explaining the EBM with 175 EBM panels, and summarise the most recent systematic reviews (SR) or RCTs in key therapeutic areas. All recommendations conform to Grade A criteria. In CVD there are 20 EBM panels which represented the more frequent panels in all the other systems.
Braunwald Heart disease  and Topol explained the RCTs in a good manner depending on therapy and the guidelines.
Harrison's Medicine (15) included this as an essential basis of the therapy. In this era of EBM it is tempting to think that all the difficult decisions practitioners face have been or soon will be solved and digested into practice guidelines and computerized reminders (15).
| Discussion|| |
The non-agreement and contradictions are not due to the usual differences between physicians, but actually whether this drug or group of drugs is proven to be effective or not in the outcome, and this leads to the confusion and contradiction.
The inotropic action of digoxin, in the past thought to be essential and the reason for having digoxin as the first drug for CHF, but by RCTs it has been shown it causes no benefit in the long term, endpoint events, and on overall survival, but did reduce the need for hospitalization  . This changed its use to improve symptoms, arrhythmias, and to decrease hospitalization. It is unhelpful in terms of outcome. This example and other drugs have to be explained properly to medical students and general physicians; this may help to relieve some of the contradictions between physicians in the use of drugs.
| Conclusions|| |
- Prompt actions are needed to improve access and implementation of evidence based guidelines and summaries for CVD in the cardiac centers.
- Introducing evidence based therapy into the referenced and the most studied books of CVD will help to relieve many of the confusions and contradictions in treatment
- Results showed a need for correlation between basic evidence (basic sciences) and clinical evidence (EBT) in the teaching and training of physicians.
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[Table 1], [Table 2]