title: Impact of a high-fat meal on assessment of clopidogrel-induced platelet inhibition in healthy subjects.
abstract: BACKGROUND
  Ideal conditions for platelet reactivity testing are critical for optimal selection of a P2Y12 inhibitor. Data are inconsistent regarding the impact of high-fat meals on test assessment.
  
  
  METHODS
  Participants included 12 healthy subjects not taking antiplatelet drugs after a 12-hour fast. After baseline assessment, subjects were given a 600 mg dose of clopidogrel. Four hours later, maximum platelet inhibition was tested in the fasting state by light transmission aggregometry (LTA), VerifyNow P2Y12, vasodilator-stimulated phosphoprotein (VASP), and whole blood aggregometry (WBA). Subjects were then provided a high-fat meal, and platelet function was evaluated two hours later. Change in measured platelet aggregation by LTA was the primary endpoint of the study. The Wilcoxon Rank Sum test was used to compare the change in platelet reactivity between fasting and non-fasting conditions. The Spearman rho (ρ) correlation coefficient was used to evaluate the association between fasting platelet reactivity and the change following a high-fat meal.
  
  
  RESULTS
  No significant change occurred in maximal light transmission, as assessed by LTA with 5 μM ADP (p = 0.15) and with 20 μM ADP (p = 0.07). There was a significant change in the area under the curve with 5 μM ADP (p = 0.03) but not with 20 μM ADP (p = 0.18). Although there was no significant change with the VerifyNow P2Y12 assay (p = 0.16), the change was correlated with the initial fasting value (Spearman's rho p = 0.008). The VASP assay and WBA varied minimally.
  
  
  CONCLUSIONS
  The high-fat meal did not significantly alter platelet function assessment of commonly used platelet function tests. Greater intra-subject variability existed for the optically-dependent compared with non-optically dependent tests.
  
  
  BACKGROUND
  NCT01307657.
authors: Department of Pharmacy Practice, University of Nebraska Medical Center College of Pharmacy, Omaha, Nebraska 68198-6045 USA.
authors: Paul P
authors: PP
authors: Dobesh
authors: Pharmacy Department, Denver Health Medical Center, Denver, Colorado USA.
authors: Jamela F
authors: JF
authors: Urban
authors: Division of Cardiology, Texas Tech University Health Science Center, Lubbock, Texas USA.
authors: Scott W
authors: SW
authors: Shurmur
authors: University of Kentucky College of Pharmacy, Lexington, Kentucky USA.
authors: Julie H
authors: JH
authors: Oestreich
keywords: Blood platelets; Clopidogrel; Diet; High-fat; P2Y12 purinoceptor antagonist; Platelet function tests
references: Lancet. 1996 Nov 16;348(9038):1329-39
references: 8918275
references: Ann Nutr Metab. 1986;30(4):250-60
references: 3752924
references: Nutr Metab. 1980;24 Suppl 1:90-104
references: 7454140
references: Scand J Haematol. 1974;12(5):329-40
references: 4854739
references: J Am Coll Cardiol. 2007 Apr 10;49(14):1505-16
references: 17418288
references: Am J Cardiol. 2013 Aug 1;112(3):355-62
references: 23631863
references: Coron Artery Dis. 2009 May;20(3):207-13
references: 19318928
references: N Engl J Med. 2001 Aug 16;345(7):494-502
references: 11519503
references: JAMA. 2002 Nov 20;288(19):2411-20
references: 12435254
references: Lancet. 1976 Nov 6;2(7993):995-6
references: 62266
references: J Clin Pharmacol. 2012 Oct;52(10 ):1506-15
references: 22128201
references: Eur J Clin Invest. 1984 Oct;14(5):339-45
references: 6437832
references: Semin Thromb Hemost. 1999;25 Suppl 2:47-50
references: 10440423
references: Thromb Res. 1987 Dec 1;48(5):567-76
references: 3441905
references: N Engl J Med. 2009 Sep 10;361(11):1045-57
references: 19717846
references: Atherosclerosis. 1985 Aug;56(2):157-67
references: 4074453
references: Thromb Diath Haemorrh. 1973 May 10;29(2):450-60
references: 4357633
references: J Thromb Haemost. 2009 Jun;7(6):1029
references: 19422455
references: Circulation. 2005 May 24;111(20):2560-4
references: 15809367
references: Thromb Res. 1982 Jul 15;27(2):235-9
references: 7135357
references: Clin Chem Lab Med. 2010 Oct;48(10):1463-5
references: 20618093
references: J Clin Pharmacol. 2010 Jan;50(1):27-35
references: 19779037
references: Platelets. 2007 Mar;18(2):171-3
references: 17365867
references: Thromb Haemost. 2011 May;105(5):927-30
references: 21437349
references: Am J Clin Nutr. 1996 Aug;64(2):168-76
references: 8694016
references: N Engl J Med. 2005 Mar 24;352(12):1179-89
references: 15758000
references: N Engl J Med. 2007 Nov 15;357(20):2001-15
references: 17982182
references: J Am Coll Cardiol. 2011 Nov 1;58(19):1945-54
references: 22032704
references: Thromb Haemost. 1979 Feb 15;40(3):518-31
references: 425066
references: Thromb Res. 1985 Sep 15;39(6):725-32
references: 2934861