Only A Handful Of Heart Disease Recommendations Are Backed Up By Qualitative Research

Only a handful of heart disease recommendations are backed up by qualitative research

Less than 10% of recommendations for the treatment of cardiovascular diseases are based on the so-called "gold standard" - data from large randomized controlled clinical trials and meta-analyzes. But scientists emphasize that current guidelines remain the most important document on which treatment should be based.

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Less than 10% of recommendations for the treatment of cardiovascular diseases are based on the so-called "gold standard" - data from large randomized controlled clinical trials and meta-analyzes. This is evidenced by the results of a review of treatment guidelines conducted by the Duke Clinical Research Institute and published online in JAMA.

A similar analysis 10 years ago found a similar situation - only 12.5% ​​of treatment protocols relied on the highest level of evidence.

“There was a call for better performance in 2009 … But, in fact, despite some initiatives and a greater emphasis on conducting randomized controlled trials, the gap between evidence and need for evidence has not diminished,” said senior study author Renato Lopes., cardiologist and professor of medicine at the Duke Institute.

The research team reviewed the evidence base for over 6,300 treatment protocols issued by the American College of Cardiology / American Heart Association (ACC / AHA) and the European Society of Cardiology (ESC).

These treatment standards are used to identify and make clinical decisions for major cardiovascular conditions such as high blood pressure and high cholesterol, and adherence to them is believed to improve patients' well-being. The quality of the data underpinning the recommendations is important to minimize any inherent bias and confounding factors that may subsequently affect real patients in real life settings.

Treatment guideline committees categorize recommendations by level of evidence:

A - based on evidence from numerous randomized controlled trials and meta-analyzes;

B - supported by one randomized controlled trial or non-randomized trials (observational analysis);

C - set by expert opinion.

According to this review, only 8.5% of ACC / AHA recommendations are based on level A data, 50% on level B, and 41.5% on level C.

“Patients must rely on the scientific knowledge of the care they receive to be reliable and will lead to improved outcomes. Progress in reducing deaths from cardiovascular disease has slowed over the past few years, and improving the evidence base for treatment guidelines could help prevent this trend,”said study lead author Alexander Fanaroff.

But medical practitioners cannot just wait for the highest level of evidence, so patients receive treatment based on available guidelines, even if they are not optimal. The accompanying JAMA editorial notes that some of the recommendations are so obvious that it would be unethical to abandon them, even if they are not supported by a randomized trial.

This issue is not just about cardiovascular health guidelines. Many medical decisions are based on weak evidence or even human guesswork, wrote oncologist Vinay Prasad of the Oregon Health ana Science University who studied the phenomenon.