Prognostic effect of mean platelet volume in patients with coronary artery disease

Large platelets with high haemostatic activity may lead to increased platelet aggregation.. Mean platelet volume (MPV), an indicator of platelet reactivity, may emerge as a prognostic marker in patients with coronary artery disease (CAD). It was the objective of this study to conduct a systematic review and meta-analysis to assess prognostic effects of MPV on cardiovascular events (CVE) in CAD patients. We searched MEDLINE and SCOPUS from inception to January 2, 2014. All studies that reported MPV and the incidence of cardiovascular events in CAD patients were included. Two reviewers independently extracted the data. A random-effects model was applied for pooling the mean difference of MPV between patients with vs without CVE. Among 30 eligible studies, eight studies reported mean difference of MPV between CVE groups, 11 studies reported MPV dichotomous into high vs low MPV groups, and 11 studies reported both. The pooled mean difference was 0.69 fL (95 %CI = 0.36, 1.01), i.e. patients with CVE had a MPV about 0.69 fL higher than non-CVE. Patients with higher MPV were about 12 % more likely to die than patients with lower MPV (RR 1.12; 95 %CI = 1.02-1.24). However, pooling these effects was based on high heterogeneity and the source of heterogeneity could not be identified. This might be explained by many differences among included studies (e.g. study population, outcomes of interest, analysate, time between blood collection and MPV analysis, etc). These findings suggest that MPV may be a useful prognostic marker in patients with CAD.