Relative platelet reduction provides a better pathophysiologic signature of coagulopathy in sepsis than absolute platelet count: A large multicenter eICU database analysis

Abstract

BackgroundIn sepsis-associated coagulopathy and disseminated intravascular coagulation, the relative platelet reduction may reflect the severity of the coagulopathy. However, there is little evidence to support its clinical significance and most of the coagulopathy criteria in sepsis focus on absolute platelet count. The aim of this study was to estimate the impact of the relative platelet reduction and the absolute platelet count on outcomes in sepsis.MethodsMulticenter retrospective observational study was performed using the eICU Collaborative Research Database, which includes 335 intensive care units (ICUs) in the United States. Patients with sepsis and with an ICU stay of longer than 2 days were included. The estimated effect of the relative platelet reduction and the absolute platelet count on mortality and coagulopathy-related complications were evaluated.ResultsOf 30,114 septic patients, 26,193 were included in this study. Multivariable mixed-effect logistic regression analysis revealed marked in-hospital mortality risk with more profound degrees of relative reduction in platelet count between day 1 and day 2, which is independent from the resultant absolute platelet count. Adjusted odds ratio (OR) for in-hospital mortality was 1.28 (95% confidence interval [CI], 1.23-1.32); 1.86 (95% CI, 1.75-1.97); 2.99 (95% CI, 2.66-3.36); and 6.05 (95% CI, 4.40 - 8.31) for 20-40%, 40-60%, 60-80%, and more than 80%, respectively, compared to less than 20% decrease in platelet. Interaction for mortality odds between relative platelet reduction and resultant absolute platelet count was not found (p=0.33). In multivariate logistic regression analysis, the estimated effects of platelet reduction ≧50% for coagulopathy-related complications were greater than that of platelet counts ≦100,000/μL on day 2 (OR for composite outcome [95%CI], 2.03 [1.68 - 2.45] and 1.18 [1.07 - 1.30], respectively).ConclusionThe magnitude of platelet reduction not only represents mortality risk but also provides a better signature of coagulopathy in sepsis than absolute platelet count, and may, therefore, be more plausible for the criteria of coagulopathy in sepsis.