Format

Send to

Choose Destination
JAMA. 2014 Apr 9;311(14):1406-15. doi: 10.1001/jama.2014.2630.

Validation of the atherosclerotic cardiovascular disease Pooled Cohort risk equations.

Author information

1
Department of Epidemiology, University of Alabama at Birmingham2Department of Medicine, University of Alabama at Birmingham.
2
Department of Epidemiology, University of Alabama at Birmingham.
3
Department of Medicine, University of Vermont, Burlington.
4
Department of Epidemiology, Colorado School of Public Health, Aurora.
5
Department of Biostatistics, University of Alabama at Birmingham.
6
Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, Ohio.
7
Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois.
8
Department of Medicine, University of Alabama at Birmingham.

Abstract

IMPORTANCE:

The American College of Cardiology/American Heart Association (ACC/AHA) Pooled Cohort risk equations were developed to estimate atherosclerotic cardiovascular disease (CVD) risk and guide statin initiation.

OBJECTIVE:

To assess calibration and discrimination of the Pooled Cohort risk equations in a contemporary US population.

DESIGN, SETTING, AND PARTICIPANTS:

Adults aged 45 to 79 years enrolled in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study between January 2003 and October 2007 and followed up through December 2010. We studied participants for whom atherosclerotic CVD risk may trigger a discussion of statin initiation (those without clinical atherosclerotic CVD or diabetes, low-density lipoprotein cholesterol level between 70 and 189 mg/dL, and not taking statins; n = 10,997).

MAIN OUTCOMES AND MEASURES:

Predicted risk and observed adjudicated atherosclerotic CVD incidence (nonfatal myocardial infarction, coronary heart disease [CHD] death, nonfatal or fatal stroke) at 5 years because REGARDS participants have not been followed up for 10 years. Additional analyses, limited to Medicare beneficiaries (n = 3333), added atherosclerotic CVD events identified in Medicare claims data.

RESULTS:

There were 338 adjudicated events (192 CHD events, 146 strokes). The observed and predicted 5-year atherosclerotic CVD incidence per 1000 person-years for participants with a 10-year predicted atherosclerotic CVD risk of less than 5% was 1.9 (95% CI, 1.3-2.7) and 1.9, respectively, risk of 5% to less than 7.5% was 4.8 (95% CI, 3.4-6.7) and 4.8, risk of 7.5% to less than 10% was 6.1 (95% CI, 4.4-8.6) and 6.9, and risk of 10% or greater was 12.0 (95% CI, 10.6-13.6) and 15.1 (Hosmer-Lemeshow χ2 = 19.9, P = .01). The C index was 0.72 (95% CI, 0.70-0.75). There were 234 atherosclerotic CVD events (120 CHD events, 114 strokes) among Medicare-linked participants and the observed and predicted 5-year atherosclerotic CVD incidence per 1000 person-years for participants with a predicted risk of less than 7.5% was 5.3 (95% CI, 2.8-10.1) and 4.0, respectively, risk of 7.5% to less than 10% was 7.9 (95% CI, 4.6-13.5) and 6.4, and risk of 10% or greater was 17.4 (95% CI, 15.3-19.8) and 16.4 (Hosmer-Lemeshow χ2 = 5.4, P = .71). The C index was 0.67 (95% CI, 0.64-0.71).

CONCLUSIONS AND RELEVANCE:

In this cohort of US adults for whom statin initiation is considered based on the ACC/AHA Pooled Cohort risk equations, observed and predicted 5-year atherosclerotic CVD risks were similar, indicating that these risk equations were well calibrated in the population for which they were designed to be used, and demonstrated moderate to good discrimination.

PMID:
24682252
PMCID:
PMC4189930
DOI:
10.1001/jama.2014.2630
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Silverchair Information Systems Icon for PubMed Central
Loading ...
Support Center