The ACC/AHA criteria for identification of very high-risk CVD patients have limited discriminative power
Identification of vascular patients at very high risk for recurrent cardiovascular events: validation of the current ACC/AHA very high risk criteria
The ESC, ACC/AHA and WHO guidelines for the prevention of cardiovascular disease (CVD) use different clinical criteria for the identification of patients at high or very high risk (VHR) for recurrent cardiovascular (CV) events. All patients with a history of CVD are considered as VHR according to the ESC and WHO guidelines, but the ACC/AHA guidelines classify patients as having a VHR only if besides CVD they additionally have diabetes, current smoking, dyslipidaemia or progression of coronary artery disease (CAD) [1-3].
In this analysis of the SMART study and the REACH registry, the prevalence and actual risk of recurrent CV events according to the ACC/AHA VHR criteria were evaluated. Moreover, the performance of the ACC/AHA VHR criteria was compared with this of other single very high-risk factors (low eGRF, polyvascular disease, abdominal aortic aneurysm, peripheral artery disease, progression of CAD, smoking, high age, diabetes) in contemporary cohorts of patients with clinically manifest arterial disease.
- In the SMART cohort, the incidence of recurrent MACE was on average 2.4/100 person years (PY) (95% CI 2.3-2.5/100 PY) and 57% of the SMART population met the ACC/AHA criteria of VHR (incidence 2.7/100 PY, 95% CI 2.5–2.9/100 PY).
- In the REACH registry, the incidence for recurrent MACE was 5.1/100 PY (95% CI 5.0–5.3/100 PY) and 64% of the REACH participants met the AHA/ACC criteria for VHR.
- Patients who did not meet the ACC/AHA criteria for VHR, had a MACE incidence of 2.0/100 PY in SMART and 3.9/100 PY in REACH.
- There was a statistically significant difference in incidence rates between patients meeting the ACC/AHA VHR criteria and those who did not, in both cohorts.
- The highest incidence for recurrent MACE were found in patients with an eGFR <45mL/min/1.73m2 (incidence in SMART 6.9/100 PY, 95% CI 5.8-8.1/100 PY and incidence in REACH 9.4/100 PY, 95% CI 8.8–10.1/100 PY), as well as in patients with polyvascular disease (incidence 5.0 in SMART and 7.7/100 PY in REACH).
- The ACC/AHA VHR criteria had poor to moderate discrimination in identifying patients who developed a recurrent CV event during follow-up. C-statistics were 0.54 (95% CI 0.52–0.55) in SMART and 0.53 (95% CI 0.52–0.53) in REACH.
- The single risk factors polyvascular disease and age >70 led to improved re-classification of patients at very high risk of a recurrent event during follow-up, when compared with the ACC/AHA VHR criteria.
- The proportion of patients with a predicted 10-year risk ≥30% was much higher in patients aged ≥70 years (68% in SMART and 58% in REACH) when compared to the overall study populations (25% in SMART and 30% in REACH).
- In patients at very high risk according to the ACC/AHA criteria, the proportion of patients with >30% 10-year risk was 29% in SMART and 33% REACH, while in patients who were not at VHR according to the ACC/AHA, this was 19% both in SMART and REACH.
In the SMART study and the REACH registry, single very high risk factors or simple criteria, such as the ACC/AHA VHR criteria, had limited discriminative power to identify patients at highest risk of recurrent MACE. These findings suggest that there is a need to improve the identification of very high-risk patients in the secondary CVD prevention.