The impact of thrombocytopenia on mortality in infective endocarditis - a meta-analysis

Thrombocytopenia, a condition characterized by low platelet counts, is recognized as a risk factor in various infectious diseases, but it is not commonly included in prognostic scoring systems for infective endocarditis (IE). This meta-analysis aimed to assess the relationship between thrombocytopenia and mortality in patients with IE. The study included 25 observational studies (21 retrospective and 4 prospective), covering a total of 110,411 patients diagnosed with IE. The primary outcome was in-hospital mortality associated with thrombocytopenia. Secondary outcomes included the mean difference in platelet counts between survivors and deceased patients, as well as long-term mortality. The results demonstrated that patients with thrombocytopenia had significantly higher in-hospital mortality (Odds Ratio [OR]: 1.99; 95 % Confidence Interval [CI]: 1.72-2.31; P < 0.00001). Additionally, patients who died during hospitalization had significantly lower platelet counts compared to survivors (Mean Difference [MD]: -36,750/µL; 95 % CI: -52,570 to -20,920; P < 0.00001). Long-term mortality was also elevated in thrombocytopenic patients (Hazard Ratio [HR]: 2.08; 95 % CI: 1.29-3.34; P = 0.002). These findings suggest that thrombocytopenia is significantly associated with both in-hospital and long-term mortality in patients with IE. The notable reduction in platelet counts among deceased patients further emphasizes its prognostic significance. The study highlights the need to consider thrombocytopenia in future prognostic models for IE. However, caution is advised when interpreting these results, and additional research is necessary to confirm these associations.