Cigarette smoking status and outcome among patients with acute coronary syndromes without persistent ST-segment elevation: Effect of inhibition of platelet glycoprotein IIb/IIIa with eptifibatide

Background studies have shown that cigarette smokers constitute a substanti al proportion of patients with acute coronary syndromes (ACS) and have plat elet-rich coronary thrombi. We characterized the influence of smoking statu s on outcome of patients with ACS without persistent ST-segment elevation a nd tested the hypothesis that selective inhibition of the platelet glycopro tein IIb/IIIa receptor with eptifibatide would improve outcomes among cigar ette smokers. Methods The study population included patients enrolled in the PURSUIT tria l (Platelet Glycoprotein IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy) with known smoking status presenting with ischemi c chest pain less than or equal to 24 hours and having either ischemic elec trocardiographic changes without persistent ST-segment elevation or elevate d creatine kinase MB levels. Patients were randomly assigned to receive a b olus and infusion of either eptifibatide or placebo in addition to standard therapy. The primary end point was a composite of death or nonfatal myocar dial infarction within 30 days. Results Of the 9406 patients with known smoking status, 2677 were current s mokers, 3086 were former smokers, and 3643 were nonsmokers. Cigarette smoke rs had better 30-day outcomes (12.3%, 16.8%, and 15.4% for smokers, former smokers, and nonsmokers, respectively; P = .001). However, after adjusting for differences in baseline clinical variables, smoking status was not a pr edictor of 30-day outcome (P = .45). There was a reduction in the composite end point overall with eptifibatide compared with placebo (14.3% vs 15.7%, P = .054) but no interaction Conclusions Among patients with ACS without persistent ST-segment elevation , cigarette smokers had better short-term outcomes because of their more fa vorable clinical profile. Although prior studies have suggested that smoker s more commonly have platelet-rich thrombi than nonsmokers, eptifibatide di d not result in more improvement in their outcome compared with former smok ers or nonsmokers.