Results indicated that some PFTs may have some prognostic utility , i.e. a trend for more clinical events to be associated with groups classified as ' aspirin resistant ' .
Study -level effect sizes were generally small and absolute outcome risk was not substantially different between ' aspirin resistant ' and ' aspirin sensitive ' design ations .
Based on assumptions of PFTs being able to accurately identify patients at high risk of clinical events and such patients benefiting from treatment modification , the economic model found that a test-treat strategy was likely to be cost-effective .
However , neither assumption is currently evidence based .
BACKGROUND The use of aspirin is well established for secondary prevention of cardiovascular disease .
However , a proportion of patients suffer repeat cardiovascular events despite being prescribed aspirin treatment .
It is uncertain whether or not this is due to an inherent inability of aspirin to sufficiently modify platelet activity .
This report aims to investigate whether or not insufficient platelet function inhibition by aspirin ( ' aspirin resistance ' ) , as defined using platelet function tests ( PFTs ) , is linked to the occurrence of adverse clinical outcomes , and further , whether or not patients at risk of future adverse clinical events can be identified through PFTs .
OBJECTIVES To review systematic ally the clinical effectiveness and cost-effectiveness evidence regarding the association between PFT design ation of ' aspirin resistance ' and the risk of adverse clinical outcome ( s ) in patients prescribed aspirin therapy .
To undertake exploratory model-based cost-effectiveness analysis on the use of PFTs .
Platelet function in patients with acute coronary syndrome (ACS) predicts recurrent ACS.
BACKGROUND Platelet hyperfunction contributes to acute coronary syndromes ( ACS ) . Thus , we hypothesized that platelet function under high shear stress predicts recurrent ACS during long-term follow-up of ACS patients . PATIENTS AND METHODS Consecutive ACS patients ( n = 208 ) were prospect ively followed-up for an average of 28 months . Platelet function was measured with the platelet function analyzer ( PFA-100 ; Dade Behring , Marburg , Germany ) at baseline for collagen/adenosine diphosphate closure times ( CADP-CT ) and for collagen/epinephrine closure times ( CEPI-CT ) after infusion of a uniform dose of 250 mg aspirin . RESULTS Of the conventional risk factors , only the prevalence of diabetes was higher in ACS patients with re-events . However , use of clopidogrel and use of beta blockers were also slightly lower in patients with re-events ( P < 0.05 ) . The unadjusted risk hazard ratio ( HR ) for re-events was 3.3 [ 95 % confidence interval ( 95 % CI ) : 1.4 - 7.4 ; P = 0.005 ] in those patients with the shortest CADP-CT values ( lowest quartile ) . Similarly , the risk was 2.0-fold higher ( 95 % CI : 1.1 - 3.6 ; P = 0.02 ) in ACS patients with CEPI-CT < 300 s as compared with CEPI-CT > or = 300 s. Inclusion of diabetes , clopidogrel and beta blockers in a multivariate Cox regression model enhanced the predictive value of CEPI-CT ( HR : 2.7 ) . Inclusion of von Willebr and factor levels did not alter the HR for recurrent ACS ( HR : 2.1 ; 95 % CI : 1.1 - 5.2 ; P = 0.03 ) for CEPI-CT < 300 s , but reduced the HR for CADP-CT ( HR : 2.8 , 95 % CI : 0.8 - 9.8 ; P = 0.11 ) . CONCLUSION Shortened CT values reflect biologically relevant platelet hyperfunction in patients with ACS because they predict recurrent ACS
Results indicated that some PFTs may have some prognostic utility , i.e. a trend for more clinical events to be associated with groups classified as ' aspirin resistant ' .
Study -level effect sizes were generally small and absolute outcome risk was not substantially different between ' aspirin resistant ' and ' aspirin sensitive ' design ations .
Based on assumptions of PFTs being able to accurately identify patients at high risk of clinical events and such patients benefiting from treatment modification , the economic model found that a test-treat strategy was likely to be cost-effective .
However , neither assumption is currently evidence based .
BACKGROUND The use of aspirin is well established for secondary prevention of cardiovascular disease .
However , a proportion of patients suffer repeat cardiovascular events despite being prescribed aspirin treatment .
It is uncertain whether or not this is due to an inherent inability of aspirin to sufficiently modify platelet activity .
This report aims to investigate whether or not insufficient platelet function inhibition by aspirin ( ' aspirin resistance ' ) , as defined using platelet function tests ( PFTs ) , is linked to the occurrence of adverse clinical outcomes , and further , whether or not patients at risk of future adverse clinical events can be identified through PFTs .
OBJECTIVES To review systematic ally the clinical effectiveness and cost-effectiveness evidence regarding the association between PFT design ation of ' aspirin resistance ' and the risk of adverse clinical outcome ( s ) in patients prescribed aspirin therapy .
To undertake exploratory model-based cost-effectiveness analysis on the use of PFTs .