Anemia Predicts Cardiac Events After Vascular Surgery
Even mild baseline anemia is linked to increased five-year risk of major adverse cardiac events
THURSDAY, April 17 (HealthDay News) -- In patients who undergo elective vascular surgery, preoperative anemia is a significant predictor of perioperative and long-term cardiac events, researchers report in the April 15 issue of the American Journal of Cardiology.
Martin Dunkelgrun, M.D., of the Leiden University Medical Centre in Leiden, the Netherlands, and colleagues studied 1,211 patients (77 percent men, mean age 68), including 399 (33 percent) who were anemic at baseline, 74 (6 percent) who had a major adverse cardiac event after 30 days and 199 (17 percent) who had a major adverse cardiac event after five years.
After adjustment for all clinical risk factors, the researchers found that baseline anemia was associated with an increased risk of major adverse cardiac events compared to baseline non-anemia. For mild, moderate and severe anemia, they calculated 30-day hazard ratios of 1.8, 2.3, and 4.7, respectively and five-year hazard ratios of 2.4, 3.6 and 6.1, respectively.
"Several mechanisms may contribute to anemia as a risk factor for cardiac events," the authors write. "Subclinical coronary disease may decrease the tolerance for anemia because coronary vasodilatation is not possible in the presence of significant stenosis and the cardiac oxygen extraction ratio may be limited. Also, in patients with decreased cardiac reserve, anemia may further decrease regular physiologic compensatory capacity."