Prevention of cigarette smoking-induced platelet aggregate formation by aspirin.

The purpose of this study was to determine whether aspirin could prevent a decrease in the platelet aggregate ratio that we previously found after cigarette smoking. Twenty healthy nonsmokers, who had not taken aspirin in the preceding seven days, smoked two tobacco cigarettes without filters during a 20-minute period. The mean platelet aggregate ratios before and after smoking were 0.91 and 0.80, respectively. When the experiments were repeated 48 hours later and seven to 18 hours after the ingestion of one tablet of aspirin (0.32 g), there was no decrease in the platelet aggregate ratio after smoking. The mean post-smoking platelet aggregate ration after aspirin (0.93) was significantly higher than before aspirin. We conclude that aspirin prevented cigarette smoking-induced platelet aggregate formation.