Thrombocytopenia and its association with mortality in patients with COVID‐19

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), which causes novel coronavirus disease 2019 (COVID‐19), is spreading rapidly around the world. Thrombocytopenia in patients with COVID‐19 has not been fully studied. OBJECTIVE: To describe thrombocytopenia in patients with COVID‐19. METHODS: For each of 1476 consecutive patients with COVID‐19 from Jinyintan Hospital, Wuhan, China, nadir platelet count during hospitalization was retrospectively collected and categorized into (0, 50], (50, 100], (100‐150], or (150‐) groups after taking the unit (×10(9)/L) away from the report of nadir platelet count. Nadir platelet counts and in‐hospital mortality were analyzed. RESULTS: Among all patients, 238 (16.1%) patients were deceased and 306 (20.7%) had thrombocytopenia. Compared with survivors, non‐survivors were older, were more likely to have thrombocytopenia, and had lower nadir platelet counts. The in‐hospital mortality was 92.1%, 61.2%, 17.5%, and 4.7% for (0, 50], (50, 100], (100‐150], and (150‐) groups, respectively. With (150‐) as the reference, nadir platelet counts of (100‐150], (50, 100], and (0, 50] groups had a relative risk of 3.42 (95% confidence interval [CI] 2.36‐4.96), 9.99 (95% CI 7.16‐13.94), and 13.68 (95% CI 9.89‐18.92), respectively. CONCLUSIONS: Thrombocytopenia is common in patients with COVID‐19, and it is associated with increased risk of in‐hospital mortality. The lower the platelet count, the higher the mortality becomes.