Thrombocytopenia Is Associated with COVID-19 Severity and Outcome: An Updated Meta-Analysis of 5637 Patients with Multiple Outcomes

Abstract

The COVID-19 pandemic is persistent worldwide. A prior meta-analysis suggested the association of thrombocytopenia (TCP) with more severe COVID-19 illness and high mortality. Considering newly published studies, we updated the previous meta-analysis to confirm and explain the association of TCP with COVID-19 severity and multiple outcomes. Twenty-four studies with 5637 patients with COVID-19 were included in this study. The weighted incidence of TCP in COVID-19 was 12.4% (95% confidence interval [CI], 7.9%–17.7%). Data synthesis showed that the platelet number was lower in patients with either more severe illness or poor outcomes and even lower in nonsurvivors, with weighted mean differences of −24.56 × 109/L, −22.48 × 109/L, and −49.02 × 109/L, respectively. The meta-analysis of binary outcomes (with and without TCP) indicated the association between TCP and 3-fold enhanced risk of a composite outcome of intensive care unit admission, progression to acute respiratory distress syndrome, and mortality (odds ratio [OR], 3.49; 95% CI, 1.57–7.78). Subgroup analysis by endpoint events suggested TCP to be significantly associated with mortality (OR, 7.37; 95% CI, 2.08–26.14). Overall, the present comprehensive meta-analysis indicated that approximately 12% of hospitalized patients with COVID-19 have TCP, which also represents a sign of more severe illness and poor outcomes.

Epidemiological and clinical presentations of hospitalized COVID-19 patients in Libya: An initial report from Africa

“…Platelet count was significantly lower in non-survivors, where about half of them had thrombocytopenia. Compared with the non-survivors, it was found that only one-third of survivors had low platelets (p-value = 0.001); this supports the idea that low platelet count was associated with COVID-19 disease severity, more extended hospital stay, low probability of survival, and subsequent long term mortality [ [36] , [37] , [38] , [39] , [40] ]. Another finding is D-dimer's elevation, especially in non-survivor patients.…”

Complete blood count alterations in COVID-19 patients

“…An interesting point of the subgroup analysis is that thrombocytopenia may not be significantly related to intensive care unit (ICU) admission. This aspect could be explained considering that thrombocytopenia tends to reach a significant level in the late clinical stage of COVID-19 ( 8 ).…”

An AI-guided signature reveals the nature of the shared proximal pathways of host immune response in MIS-C and Kawasaki disease

“…Thrombocytopenia, which was more pronounced in MIS-C and correlated significantly with IL15 and IL15/IL15 composite transcript score in both KD and MIS-C, has also been reported in COVID-19 and postulated because of various mechanisms [34][35][36][37][38] . In the case of KD, thrombocytopenia has been found to be associated with disease severity 40 .…”

“…In the case of KD, thrombocytopenia has been found to be associated with disease severity 51 . Similarly, in the case of COVID-19, a large meta-analysis confirmed that approximately 12% of hospitalized patients have thrombocytopenia, which represents a sign of disease severity and poor outcomes 46 .…”