Blood protein able to detect higher risk of cardiovascular events

Higher levels of pregnancy-associated plasma protein A (PAPP-A) were associated with an increased risk of cardiovascular events in people with cardiac chest pain that developed as a result of heart disease/coronary artery disease, according to a study published in CMAJ.

PAPP-A, used to screen for Down syndrome in pregnant women, has been suggested as a marker of unstable plaque in coronary arteries.

The study was conducted in 2568 patients in Tübingen, Germany, to determine if the presence of PAPP-A could help predict cardiovascular events. The study included patients who visited hospital with cardiac chest pain between December 2007 and April 2009. All patients had an echocardiogram and blood samples drawn for analysis.

Previous studies have been smaller in scale, with the largest including 670 patients.

More than half (52%) of patients had stable angina and the remaining 48% had acute coronary syndrome. The normal serum value for men and nonpregnant women is < 14 mIU/L. Serum levels in patients who had cardiovascular events in the 3 months following initial hospital admission, such as a heart attack (myocardial infarction), stroke or death, were higher (62 ± 156 mIU/L) compared with those who did not (21 ± 23 mIU/L).

"PAPP-A remained a significant independent predictor of major cardiovascular events…[as did] a history of diabetes mellitus…and atrial fibrillation," writes Dr. Stephan von Haehling, Department of Cardiology, Charité Medical School, Berlin, Germany, with coauthors. "PAPP-A remained the strongest predictor of major cardiovascular events when we restricted the analysis to patients with stable angina…and when we restricted it to patients with acute coronary syndrome."

The authors suggest that PAPP-A levels could help in evaluating risk levels of patients who present to emergency departments with cardiac chest pain.