Thrombocytopenia as a Prognostic Marker for Systemic Lupus Erythematosus: A Systematic Review and Meta-analysis

Background: Systemic lupus erythematosus (SLE) patients often exhibit hematological abnormalities, but the role of thrombocytopenia on the prognosis of SLE shows inconsistent results. The purpose of this meta-analysis was to confirm the impact of thrombocytopenia on mortality and end organ damage in patients with SLE. Materials and Methods: Three electronic databases, PubMed, Embase and Cochrane library were systematically searched to identify the eligible studies from inception to November 2017 in order to evaluate the impact of thrombocytopenia on the prognosis of patients with SLE. The summary odds ratios (ORs) and 95% confidence intervals (CIs) were used to measure the impact of thrombocytopenia on mortality and end organ damage based on the random-effects model. Results: A total of 8 studies that reported data on 2,158 patients with SLE were included. The summary OR indicated that SLE subjects with thrombocytopenia were significantly associated with an increased risk of mortality (OR: 4.57; 95% CI: 2.28-9.17; P < 0.001) and end-organ damage (OR: 3.31; 95% CI: 1.11-9.86; P = 0.031). Furthermore, the sensitivity analysis indicated stable mortality, while the result for end organ damage was variable. In addition, the patients with thrombocytopenia with disease duration < 60 months presented a greater risk for mortality than those with disease duration >= 60.0 months (P = 0.002). Conclusions: Patients with SLE and thrombocytopenia were found to be associated with an increased risk of mortality and end organ damage.