Platelet count as a prognostic marker for acute respiratory distress syndrome.

BACKGROUND

This study aimed to evaluate the role of platelet count (PLT) in the prognosis of patients with acute respiratory distress syndrome (ARDS).

METHODS

The data were extracted from the Medical Information Mart for Intensive Care database (version 2.2). Patients diagnosed with ARDS according to criteria from Berlin Definition and had the platelet count (PLT) measured within the first day after intensive care unit admission were analyzed. Based on PLT, ARDS patients were divided into four groups: PLT ≤ 100 × 10/L, PLT 101-200 × 10/L, PLT 201-300 × 10/L, and PLT > 300 × 10/L. The primary outcome was 28-day mortality. Survival probabilities were analyzed using Kaplan-Meier. Furthermore, the association between PLT and mortality in ARDS patients was assessed using a univariate and multivariable Cox proportional hazards model.

RESULTS

Overall, the final analysis included 3,207 eligible participants with ARDS. According to the Kaplan-Meier curves for 28-day mortality of PLT, PLT ≤ 100 × 10/L was associated with a higher incidence of mortality (P = 0.001), the same trends were observed in the 60-day (P = 0.001) and 90-day mortality (P = 0.001). In the multivariate model adjusted for the potential factors, the adjusted hazard ratio at PLT 101-200 × 10/L group, PLT 201-300 × 10/L, and PLT > 300 × 10/L was 0.681 [95% confidence interval (CI): 0.576-0.805, P < 0.001], 0.733 (95% CI: 0.604-0.889, P = 0.002), and 0.787 (95% CI: 0.624-0.994, P = 0.044) compared to the reference group (PLT ≤ 100 × 10/L), respectively. Similar relationships between the PLT ≤ 100 × 10/L group and 28-day mortality were obtained in most subgroups.

CONCLUSION

PLT appeared to be an independent predictor of mortality in critically ill patients with ARDS.