Performance of the ACC/AHA Pooled Cohort Cardiovascular Risk Equations in Clinical Practice
Key result
ACC/AHA pooled cohort equations predict real-world ASCVD risk with a good 0.78 c-statistic.
- c-statistic 0.78
- n=30,042
Journal of the American College of Cardiology published a graphical abstract
Its licence doesn't allow us to show a copy here.
Why the study?
The performance of the ACC/AHA pooled cohort equation for ASCVD in real-world clinical practice had not been evaluated extensively.
Does the ACC/AHA Pooled Cohort Equation accurately predict ASCVD risk in a real-world community cohort?
Key Points
- To evaluate the real-world performance of the ACC/AHA pooled cohort equations (PCE) in predicting 10-year atherosclerotic cardiovascular disease (ASCVD) risk and determine whether out-of-range clinical values or statin initiation impact predictive accuracy.
- Conducted a community-based cohort study of N=30,042 consecutive primary care adults in Olmsted County, Minnesota (1997–2000) followed through 2016 (median follow-up 16.5 years, truncated at 10 years for analysis) via the Rochester Epidemiology Project.
- Identified and duplicate-validated primary ASCVD endpoints, defined as fatal or nonfatal myocardial infarction and ischemic stroke.
- Assessed model discrimination overall and across demographic subgroups using calculated versus observed event rates and c-statistics.
- Across 30,042 adults (mean age 48.5 ± 12.2 years, 46% male), 1,555 ASCVD events occurred (5.2% event rate) compared to a mean predicted risk of 5.6% ± 8.73%.
- The PCE demonstrated good discrimination overall with a c-statistic of 0.78, spanning from 0.77 in White males to 0.81 in non-White females.
- Out-of-range risk factor values (age, blood pressure, cholesterol) and post-baseline statin initiation did not significantly affect model performance.
Study Design
Type
Cohort (n=30,042)
Structured PICO
Does the ACC/AHA Pooled Cohort Equation accurately predict ASCVD risk in a real-world community cohort?
P
Population
30,042 adults seeking primary care in Olmsted County, Minnesota, followed for 10 years to validate the ACC/AHA pooled cohort equation for ASCVD risk.
E
Exposure
Application of the ACC/AHA Pooled Cohort Equations (PCE) for ASCVD risk prediction
O
Outcome
ASCVD events (nonfatal and fatal myocardial infarction and ischemic stroke) at 10 yearshard clinical
Main Result
Effect estimate: c-statistic 0.78
The ACC/AHA Pooled Cohort Equations perform well for predicting ASCVD risk in a real-world community cohort, even when including out-of-range values or statin initiation.
Key expert perspectives
Captured external expert commentary on this paper, strongest first. Original sources are linked where available.
“As such, they are well tailored to begin the discussion regarding risk and need for medical therapy for primary prevention of ASCVD. After this initial step, the personalization of risk to the individual patient through consideration of individual risk-enhancing factors and the use of coronary artery calcium testing in selected patients to reclassify risk, in the context of a clinician-patient discussion, will lead to smarter recommendations regarding which patients should take low-density lipoprotein cholesterol–lowering therapy and which patients may reasonably defer medication initiation.”
“When you have a patient that doesn't fall within the normal numbers of what the original calculator was [when it was] made several years ago, you can still have good enough information to decide whether to start some of this therapy.”
FLFrancisco Lopez-JimenezCardiologist, Mayo Clinic
“The study shows that this tool is reliable, not only in light of new cholesterol-lowering drugs, but for patients who previously were not evaluated with the PCE because maybe their blood pressure was higher or lower than the standards, or they did not fit the age profile, for example. By including patients with values outside the accepted range, I think we can calculate the risk for heart attacks in another 20% to 25% of patients, which is not small.”
Implication
May warrant caution applying current equations to statin decisions; leaves open need for recalibrated models validated in contemporary cohorts.
Abstract
BACKGROUND The performance of the American College of Cardiology/American Heart Association pooled cohort equation (PCE) for atherosclerotic cardiovascular disease (ASCVD) in real-world clinical practice has not been evaluated extensively. OBJECTIVES The goal of this study was to test the performance of PCE to predict ASCVD risk in the community, and determine if including individuals with values outside the PCE range (ie, age, blood pressure, cholesterol) or statin therapy initiation over follow-up would significantly affect PCE predictive capabilities. METHODS The PCE was validated in a community-based cohort of consecutive patients who sought primary care in Olmsted County, Minnesota, between 1997 and 2000, followed-up through 2016. Inclusion criteria were similar to those of PCE derivation. Patient information was ascertained by using the record linkage system of the Rochester Epidemiology Project. ASCVD events (nonfatal and fatal myocardial infarction and ischemic stroke) were validated in duplicate. Calculated and observed ASCVD risk and c-statistics were compared across predefined groups. RESULTS This study included 30,042 adults, with a mean age of 48.5 ± 12.2 years; 46% were male. Median follow-up was 16.5 years, truncated at 10 years for this analysis. Mean ASCVD risk was 5.6% ± 8.73%. There were 1,555 ASCVD events (5.2%). The PCE revealed good performance overall (c-statistic 0.78) and in sex and race subgroups; it was highest among non-White female subjects (c-statistic 0.81) and lowest in White male subjects (c-statistic 0.77). Out-of-range values and initiation of statin medication did not affect model performance. CONCLUSIONS The PCE performed well in a community cohort representing real-world clinical practice. Values outside PCE ranges and initiation of statin medication did not affect performance. These results have implications for the applicability of current strategies for the prevention of ASCVD.
Discussion
No takes yet. Share an insight, caveat, or question.
Cite This Study
Medina‐Inojosa et al. (2023) conducted a cohort in Atherosclerotic cardiovascular disease (n=30,042). ACC/AHA pooled cohort equation (PCE) was evaluated on ASCVD events (nonfatal and fatal myocardial infarction and ischemic stroke) (c-statistic 0.78). The ACC/AHA pooled cohort equation demonstrated good overall performance for predicting ASCVD risk in a real-world community cohort (c-statistic 0.78).