THURSDAY, March 21, 2019 (HealthDay News) -- Only a small proportion of recommendations in major cardiovascular society guidelines are supported by evidence from multiple randomized controlled trials (RCTs) or a single large RCT, according to a study published in the March 19 issue of the Journal of the American Medical Association. This cardiovascular medicine theme issue was released early to coincide with the annual meeting of the American College of Cardiology, held from March 16 to 18 in New Orleans.
Alexander C. Fanaroff, M.D., from Duke University in Durham, North Carolina, and colleagues examined the class and level of evidence (LOE) supporting current major cardiovascular society guideline recommendations and changes in LOE over time. The number of recommendations and distribution of LOE were determined for current American College of Cardiology/American Heart Association (ACC/AHA) and European Society of Cardiology (ESC) clinical guideline documents.
The researchers found that among the 26 current ACC/AHA guidelines with 2,930 recommendations, 8.5, 50.0, and 41.5 percent of the recommendations were classified as LOE A, LOE B, and LOE C, respectively (median, 7.9 percent LOE A recommendations). Across 25 current ESC guideline documents with 3,399 recommendations, 14.2, 31.0, and 54.8 percent of recommendations were classified as LOE A, LOE B, and LOE C, respectively. Comparing current guidelines with previous versions, there was no increase in the proportion of recommendations that were LOE A in the ACC/AHA (median, 9.0 [current] versus 11.7 percent [prior]) or ESC guidelines (median, 15.1 versus 17.6 percent).
"These results demonstrate that efforts over the past decade to simplify and facilitate clinical trials have not yet translated into an evidence base better supported by RCTs," the authors write.
Several authors disclosed financial ties to the pharmaceutical and medical device industries.