- Recommendations from major cardiovascular societies are most often not supported by findings from randomized controlled trials (RCTs), suggesting a weak evidence base.
Why this matters
- Clinicians rely on guidelines from the American College of Cardiology/American Heart Association (ACC/AHA) and European Society of Cardiology as cornerstones of clinical decision-making, so a weak evidence base is cause for concern.
- Editorial notes that a low level of evidence (LOE) underlying many class I recommendations is a “contentious point” and asks if these class I recommendations can be justified.
- Only 248 (8.5%) of 2930 recommendations in 26 available ACC/AHA guidelines are LOE A (supported by multiple RCTs).
- Only 484 (14.2%) of 3399 recommendations from 25 available ESC guidelines are LOE A.
- Comparison of median rates with those from previous guidelines showed little difference:
- ACC/AHA: current, 9.0% vs 11.7% previous;
- ESC: current, 15.1% vs 17.6% previous.
- In the past 2 years, only 5.7% of ACC/AHA recommendations were LOE A.
- Vs ACC/AHA, ESC recommendations have a higher proportion of class 1, LOE A recommendations.
- Guidelines comparison.
- Outcome: proportion with LOE A.
- Funding: Not specified; some authors report industry ties.
- Does not include guidelines updates focused on a few select recommendations.