Predictive validity of the ACC/AHA pooled cohort equations in predicting residual-specific mortality in a national prospective cohort study of adults in the United States

OBJECTIVE: The predictive validity of the Pooled Cohort risk (PCR) equations for residual-specific mortality (deaths not resulting from the 9 leading causes of death) among a national sample of U.S. adults has not previously been evaluated, which was the purpose of this study. METHODS: Data from the 1999-2010 National Health and Nutrition Examination Survey were used, with participants followed up through 31 December 2011 to ascertain mortality status. The analyzed sample included 11,171 cardiovascular disease-free adults (40-79 years of age). The 10-year risk of a first atherosclerotic cardiovascular disease (ASCVD) event was determined from the PCR equations. RESULTS: For the entire sample, 849,202 person-months occurred with an incidence rate of 0.29 (95% CI: 0.25-0.33) residual-specific deaths per 1,000 person-months. The unweighted median follow-up duration was 72 months. For all analyses, ASCVD risk score (via the PCR equations) was significantly associated with residual-specific mortality. In a fully adjusted model including moderate-to-vigorous physical activity (MVPA), obesity, age (yrs; continuous measure), gender (male/female) and race-ethnicity (Mexican American, non-Hispanic white, non-Hispanic black and other) as covariates, those with an ASCVD ≥ 20 (vs. < 20) had a 91% increased hazard of residual-specific death during the follow-up period (HR = 1.91; 95% CI: 1.10-3.31). Expressed as probability, there was a 66% chance that those with ASCVD ≥ 20 (vs. < 20) would have a residual specific-death during the follow-up period. CONCLUSION: The 10-year predicted risk of a first ASCVD event via the PCR equations was directly associated with residual-specific mortality among those free of cardiovascular disease (CVD) at baseline, providing evidence of predictive validity of the PCR equations among this national sample of U.S. adults.