Real-World Data May Conflict with Clinical Trial Data

Discrepancies found when comparing real-world findings to clinical trial findings.

New studies presented at the American College of Cardiology’s (ACC) 2017 meeting used data gathered from ACC’s PINNACLE Registry to evaluate real-world findings against clinical trials.

These studies are part of ACC’s Research to Practice initiative, which highlights cardiovascular research that may be used to improve clinical practice.

Included in the first study were 31,008 patients with acute coronary syndrome (ACS) in the PINNACLE Registry from 2013 to 2014, compared with patients in the IMPROVE-IT clinical trial.

The researchers found that only 35.3% of patients included in the registry would have qualified to participate in the trial. Patients in the registry had more cardiovascular comorbidities and lower rates of statin, aspirin, ACE inhibitors, ARBs, and beta blockers than those in the trial, according to the study.

“It is unclear if the benefit seen with simvastatin/ezetimibe used in the trial translates to many current ACS patients,” the authors said. “In addition, with current guidelines recommending high-intensity statins for all ACS patients, the impact (…) is likely further reduced.”

In the second study, the authors found that “the proportion of adult outpatients in contemporary cardiovascular practice potentially eligible for PCSK9 inhibitor therapy varied according to LDL-C goal and practice.”

They noted that the FDA recently approved PCSK9 inhibitors for patients who have familial hypercholesterolemia (FH) or clinical atherosclerotic cardiovascular disease (ASCVD).

Included in the study were 631,107 patients, 11,244 patients had suspected FH and 192,176 patients had ASCVD, according to the study. The authors found that patients treated with high-intensity statin who were potentially eligible for PCSK9 therapy varied according to LDL cholesterol goals. Potentially eligible patients also varied among practices, with a median of 9.6%.

Findings from a third study suggest that patients with atrial fibrillation (AFib) may benefit from a weight reduction program, as indicated by the LEGACY trial.

The authors found that 56.4% of patients in the PINNACLE Registry met the trial enrollment criteria. However, registry patients tended to be older, female, and had multiple comorbidities, including hypertension, diabetes, and coronary artery disease. Registry participants also had significantly lower rates of tobacco and alcohol abuse than those included in the trial.

Findings from the clinical trial suggested “that significant (>10% ) weight reduction can result in a 6-fold greater likelihood of AFib-free survival,” according to the authors.

These findings, in addition to lower rates of tobacco and alcohol abuse, suggest that a structured weight loss program could lead to an even more substantial weight loss among patients with AFib, according to the study.

The results from these studies suggest that results from clinical trials may not always be accurate in real-world situations, and should be interpreted cautiously.