Abstract 18490: The Use of a Personalized Gene Expression Score in Women Presenting to Primary Care With Symptoms of Suspected Obstructive Coronary Artery Disease Improves Clinical Decision Making Around Non-Invasive Diagnostic Testing: Gender-Specific Results From the IMPACT-PCP (Investigation of a Molecular Personalized Coronary Gene Expression Test on Primary Care Practice Pattern) Trial
Introduction: Better methods are needed to evaluate symptomatic patients with suspected obstructive coronary artery disease (CAD), particularly among women as current methods overestimate disease prevalence. A previously validated blood-based diagnostic test with a negative predictive value of 96% among patients with low gene expression score (GES ≤ 15) uses expression levels of 23 genes to determine the likelihood of a patient having at least one vessel with ≥50% coronary artery stenosis. Use of a GES early in the diagnostic work-up for obstructive CAD may impact quality and efficiency of care.
Hypothesis: In this gender-based analysis, we hypothesized that GES results would lead to a change in the clinician’s diagnostic assessment of women presenting with symptoms suggestive of obstructive CAD.
Methods: The IMPACT-PCP Trial (NCT01594411) evaluated 251 consecutive patients with no prior history of CAD who presented to nine primary care clinicians for evaluation of chest pain and related symptoms and underwent GES testing. The clinicians outlined their diagnostic strategy before and after GES results were known. The primary outcome was the decision change in the diagnostic strategy pre/post GES testing as measured by regression modeling. In this pre-specified secondary analysis, we focused on the assessment of women in this prospective cohort.
Results: There were 140 women (56%) eligible for analysis, with mean age 59 years (SD± 13). Mean GES was 11 (SD± 9), with 76% (n=107) of women patient with low GES. Following GES, a change in the evaluation plan was noted in 83 patients (59% observed vs 10% expected change, p<0.001). More patients had a decreased (n=69, 49%) vs increased (n=14, 10%) intensity of testing (p<0.001). In particular, 96% (66/69) of patients with decreased testing had low GES (≤ 15), while 93% (13/14) of patients with increased testing had elevated GES. There has been one MACE event reported (judged as not related to CAD status by the clinician) over 30 days of follow-up.
Conclusions: The GES showed clinical utility in the evaluation of suspected obstructive CAD by affecting clinical decision making among primary care practitioners and was associated with an overall relevant reduction in diagnostic test utilization among women with low GES.
- © 2013 by American Heart Association, Inc.