Elevated WBC at acute MI admission raises mortality. (Acute Coronary Syndromes).
"This is true even within a range of WBC counts that's considered normal--between 5,000 and 10,000/[mu]L," said Dr. Yen of the Cleveland Clinic Foundation.
This finding--from a retrospective analysis of 2,253 patients with unstable angina or non-Q-wave MI enrolled in the Platelet IIb/IIIa Antagonism for the Reduction of Acute Coronary Syndrome Events in a Global Organization Network-A (PARAGON A) trial--confirms the role of inflammation in acute coronary syndromes.
An elevated WBC is not a specific marker of inflammation. But compared with specific inflammatory markers such as C-reactive protein tumor necrosis factor, and interleukin 6, the admission WBC offers the advantages of being universally available and easily interpreted at a glance.
Patients in the bottom quartile for WBC--a value of 6,800/[mu]L or less--had a 6-month all-cause mortality of 4.6%. With each successive WBC quartile, mortality climbed by an absolute 1% such that individuals in the top quartile, with a WBC greater than 9,800/pt, had a 6-month mortality of 7.6%. The median WBC in PARAGON A was roughly 8,000/[mu]t. This was associated with a 6-month mortality of 6%. Mortality was nearly twice as high in a patient who presented with a WBC of 15,000/[mu]L.
After adjusting for demographic factors, comorbidities, and treatment strategy admission WBC remained an independent predictor. For each 1,000 [mu]L of WBC, the 6-month mortality risk rose by 9.3%. A WBC of l0,000/mL in PARAGON-A participants conferred a mortality risk comparable to that of having diabetes.