Nonselective beta-blockers and development of portal vein thrombosis in liver cirrhosis: a systematic review and meta-analysis.

Portal vein thrombosis (PVT), which is associated with reduced portal vein velocity, is considered to be an indicator for worse outcomes in liver cirrhosis. Nonselective beta-blockers (NSBBs), which are widely used for primary and secondary prophylaxis of esophageal variceal bleeding in liver cirrhosis, can significantly decrease the portal vein velocity. We proposed a hypothesis that the use of NSBBs might facilitate the development of PVT in cirrhotic patients. The PubMed, EMBASE, and Cochrane Library databases were searched. Major meeting abstracts and randomized-controlled trials regarding the use of NSBBs in liver cirrhosis were also hand-searched. The number of patients who developed PVT in groups treated with or without NSBBs was pooled. Odds ratios (ORs) or risk ratios (RRs) with 95% confidence intervals (CIs) were calculated. Subgroup meta-analyses were performed according to the type of studies, region, and study quality. Meta-regression and sensitivity analyses were performed to explore the source of heterogeneity. Nine of the 6416 retrieved papers were finally included. Overall, meta-analysis demonstrated that NSBBs were significantly associated with the development of PVT (OR 4.62, 95% CI 2.50-8.53; p < 0.00001). The heterogeneity was statistically significant (I2 = 80%; p < 0.00001). Subgroup meta-analyses still demonstrated a significantly positive association of NSBBs with the development of PVT in cohort studies (RR 2.57, 95% CI 1.46-4.51; p = 0.001) and case-control studies (OR 8.17, 95% CI 2.46-27.06; p = 0.0006). Sensitivity analyses based on subgroups find the source of heterogeneity. Based on the systematic review and meta-analysis, we found that the use of NSBBs increased a 4.62-fold risk of PVT in cirrhotic patients.