Clinical descriptors can assist clinicians in identifying high-risk patients within the range of risk for outpatients with atherothrombosis, according to a substudy of the REACH trial, presented this week at the European Society of Cardiology (ESC) conference in Stockholm, Sweden, and simultaneously published in the Journal of the American Medical Association.
"Patients with atherothrombosis are at elevated risk of ischemic events but, depending on their specific manifestations of atherothrombosis, may have varying degrees of future risk for ischemic events," the authors wrote. "For clinicians, the ability to identify rapidly the major determinants of risk among patients with atherosclerosis would be useful to triage novel preventive therapies toward those at the higher end of the spectrum."
Deepak L. Bhatt, MD, from the VA Boston Healthcare System, Brigham and Women's Hospital and Harvard Medical School in Boston, and colleagues studied 45,227 patients who were enrolled in the REACH (Reduction of Atherothrombosis for Continued Health) study.
Detailed information was gathered at baseline, with additional annual follow-up at one, two, three and four years. The patients, enrolled between 2003 and 2004 and followed up until 2008, had a dominant presence of hypertension and hypercholesterolemia—with 81.3 percent and 70.4 percent of patients, respectively. Additionally, polyvascular disease (atherosclerotic disease in multiple arterial territories) was present in 15.9 percent of patients and 48.4 percent had prior ischemic events, with 28.1 percent of those having an ischemic event within the previous year, according to the authors.
During the follow-up period, 5,481 patients experienced cardiovascular events including 2,315 with cardiovascular death, 1,228 with MI, 1,898 with stroke and 40 with both an MI and stroke occurring on the same day.
Additionally, Bhatt and colleagues found that among patients with atherothrombosis, those with a prior history of ischemic events at baseline had the highest rate of subsequent ischemic events, while patients with stable coronary, cerebrovascular or peripheral artery disease had a lower risk. Patients without established atherothrombosis but with risk factors only had the lowest risk of subsequent ischemic events.
"Among all categories of patients, diabetes substantially increased the risk of future ischemic events," the authors wrote. "In those with established atherothrombosis, polyvascular disease was a particularly strong independent risk factor, even stronger than diabetes."
These two factors were associated with significantly increased risk of the composite endpoint of cardiovascular death, MI or stroke, as well as the individual components of this composite; in addition, they were associated with a significant increase in the risk of cardiovascular hospitalization, the researchers reported. “When included in the composite endpoint, cardiovascular hospitalization was associated with nearly doubling of the event rate in all subpopulations analyzed and tracked well with the more objective triple ischemic endpoint,” they wrote.
Bhatt and his colleagues concluded that this analysis of “a contemporary, international cohort of patients at various stages of atherothrombosis shows that there is a whole spectrum of ischemic risk in patients with risk factors or with established cardiovascular disease and that easily ascertainable clinical characteristics are the prominent factors associated with a high risk of future ischemic events."
Additionally, they wrote that these findings may help in the identification of high-risk populations who may deserve “intensive preventive efforts with novel therapies and also in the planning of future clinical trials.”