Circulating microparticles in patients after ischemic stroke: a systematic review and meta-analysis

Microparticles (MPs), a class of cell products with biological activities, have been found to participate in a series of vascular activities. The aim of this article is to investigate the changes in the concentrations of MPs after ischemic stroke by meta-analysis. According to pre-established criteria, a strict screening of articles was performed through the Medline and Embase databases. Subsequently, the included studies were subjected to quality assessment and data extraction. Finally, a meta-analysis was performed on seven major outcomes from 985 noncerebrovascular disease controls and 988 ischemic stroke patients. The pooled concentrations of total MPs (TMPs), endotheliocyte-derived MPs (EMPs), platelet-derived MPs (PMPs), erythrocyte-derived MPs (RMPs), leukocyte-derived MPs (LMPs), and monocyte-derived MPs (MMPs) were significantly increased in the ischemic stroke patients compared to the noncerebrovascular disease controls, with the results as follows: TMPs [standardized mean difference (SMD), 1.12; 95% confidence interval (CI), 0.26-1.97; p=0.01], EMPs (SMD, 0.90; 95% CI, 0.67-1.13; p<0.00001), PMPs (SMD, 1.15; 95% CI, 0.69-1.60; p<0.00001), RMPs (SMD, 1.14; 95% CI, 0.57-1.71; p<0.0001), LMPs (SMD, 1.42; 95% CI, 0.74-2.10; p<0.0001), and MMPs (SMD, 1.09; 95% CI, 0.59-1.60; p<0.0001). However, the pooled concentration of lymphocyte-derived MPs (LyMPs) demonstrated no significant difference between the patients and the controls (SMD, 0.22; 95% CI, -0.19 to 0.63; p=0.29). The available data indicated that the circulating MPs, except for LyMPs, play an important role in the development and prognosis of ischemic stroke.