The preventive effect of antiplatelet therapy in acute respiratory distress syndrome: a meta-analysis

BACKGROUND Acute respiratory distress syndrome (ARDS) is a life-threatening condition with high mortality that imposes a serious medical burden. Antiplatelet therapy is a potential strategy for preventing ARDS in patients with a high risk of developing this condition. A meta-analysis was performed to investigate whether antiplatelet therapy could reduce the incidence of newly developed ARDS and its associated mortality in high-risk patients. METHODS The Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Embase, Medline, and the Web of Science were searched for published studies from inception to 26 October 2017. We included randomized clinical trials, cohort studies and case-control studies investigating antiplatelet therapy in adult patients presenting to the hospital or ICU with a high risk for ARDS. Baseline patient characteristics, interventions, controls and outcomes were extracted. Our primary outcome was the incidence of newly developed ARDS in high-risk patients. Secondary outcomes were hospital and ICU mortality. A random-effects or fixed-effects model was used for quantitative synthesis. RESULTS We identified nine eligible studies including 7660 high-risk patients who received antiplatelet therapy. Based on seven observational studies, antiplatelet therapy was associated with a decreased incidence of ARDS (odds ratio (OR) 0.68, 95% confidence interval (CI) 0.52-0.88; I2 = 68.4%, p = 0.004). In two randomized studies, no significant difference was found in newly developed ARDS between the antiplatelet groups and placebo groups (OR 1.32, 95% CI 0.72-2.42; I 2 = 0.0%, p = 0.329). Antiplatelet therapy did not reduce hospital mortality in randomized studies (OR 1.15, 95% CI 0.58-2.27; I 2 = 0.0%; p = 0.440) or observational studies (OR 0.80, 95% CI 0.62-1.03; I2 = 31.9%, p = 0.221). CONCLUSIONS Antiplatelet therapy did not significantly decrease hospital mortality in high-risk patients. However, whether antiplatelet therapy is associated with a decreased incidence of ARDS in patients at a high risk of developing the condition remains unclear.