title: Aspirin failure course during exercise and its connection with soluble CD40L.
abstract: BACKGROUND
  The aspirin failure (resistance) is a still discussed and highly studied problem. This phenomenon is observed in rest, but could be precipitated by an exercise. The aspirin resistance was also linked with the inflammatory process which is a key event for the atherosclerosis development. Platelets seem to play an important role also in that setting, probably by the CD40-CD40L axis. The aim of the study was to assess the frequency of the aspirin failure induced by the exercise and the role of sCD40L in that regard.
  
  
  METHODS
  The study included 40 patients with established coronary artery disease. The control group consisted of 10 patients without coronary artery disease matched for age. All patients and controls were on 75 mg of aspirin for at least 30 days and had treadmill testing and blood collected for measurement of sCD40L and optical platelet aggregation with ADP, collagen and arachidonic acid. Aspirin resistance was defined as a maximal aggregation with ADP and collagen exceeding 70%.
  
  
  RESULTS
  There were 15 aspirin-resistant patients in the studied group (37%). There were significantly higher concentration of sCD40L (ng/ml) in aspirin-resistant patients in comparison with aspirin-sensitive ones before testing (7,9 +/- 2,5 vs. 5,1 +/- 3,5, p < 0,05) and on the top of it (8,1 +/- 2,9 vs. 4,5 +/- 3,9, p < 0,05). There were 3 persons who become resistant on the top of the exercise which was connected with the significant increase of sCD40L concentration in that group (from 7,6 +/- 1,9 before exercise to 10,1 +/- 2,9 on the top of the exercise, p < 0,05). There was also a positive correlation between the sCD40L level before and on the top of the exercise in an aspirin-resistant group (r = 0,48 for both, p < 0,05). Patients who were aspirin-resistant at rest had also significant elevation of platelet aggregation on the top of the exercise (ADP (%) from 90,5 +/- 8,6 to 95,0 +/- 6,5, p < 0,05 and collagen (%) from 87,8 +/- 8,7 to 92,1 +/- 8,0, p < 0,05).
  
  
  CONCLUSIONS
  1. Aspirin resistance phenomenon is present in about 37% patients on 75 mg aspirin daily.2. Aspirin-resistant patients have higher platelet aggregation during the exercise.3. Moderate physical exercise provokes 12% increase in the aspirin resistance phenomenon occurrence.4. Aspirin resistance is connected with higher sCD40L level at rest and exercise provoked aspirin resistance is connected with the sCD40L concentration increase.
authors.affiliation: Department of Cardiology, Wroclaw Medical University, Pasteur 4 Street, 50-367 Wroclaw, Poland. wiktor6@wp.pl
authors.forename: Wiktor
authors.initials: W
authors.lastname: Kuliczkowski
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Kobusiak-Prokopowicz
authors.forename: Iwona
authors.initials: I
authors.lastname: Prajs
authors.forename: Bozena
authors.initials: B
authors.lastname: Karolko
authors.forename: Walentyna
authors.initials: W
authors.lastname: Mazurek
mesh_terms: D000368:Aged; D001241:Aspirin / Q000494:pharmacology*; D023201:CD40 Ligand / Q000097:blood*; D003094:Collagen / Q000097:blood; D004351:Drug Resistance; D015444:Exercise; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000097:blood / Q000503:physiopathology*; D009994:Osmolar Concentration; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*
chemical_list: D010975:Platelet Aggregation Inhibitors; D023201:CD40 Ligand; D003094:Collagen; D001241:Aspirin