Obstructive sleep apnea syndrome (OSAS) is considered a low-grade chronic inflammatory disease. Interleukin-6 (IL-6) is one of the most significant inflammatory markers and an excellent proxy for the inflammatory/immune system. The present meta-analysis and meta-regression aimed at comparing plasma and serum levels of IL-6 between individuals (children and adults) with OSAS and healthy controls. Four databases, PubMed/Medline, Scopus, Cochrane Library, and Web of Science, were comprehensively searched to retrieve articles published up to December, 2019, with no further restrictions. RevMan 5.3 software was used to calculate the crude mean difference (MD) and 95% confidence interval (CI). The results of funnel plots and meta-regression were analyzed by the CMA 2.0 software. Sixty-three studies (57 with adults; six with children) were included in the present meta-analysis. For adults, 37 studies reported significantly higher serum IL-6 levels and 20 reported significantly higher plasma IL-6 levels for those with OSAS than for healthy controls [pooled MD of 2.89 pg/ml (P < 0.00001) and pooled MD of 2.89 pg/ml (P < 0.00001), respectively]. The pooled analysis of serum and plasma IL-6 levels in children with OSAS compared with controls revealed that only the MD of plasma IL-6 levels was significant (MD = 0.84 pg/ml, P = 0.004). Results of the meta-regression showed that greater age was associated with higher serum IL-6 levels. Egger's test revealed a publication bias across the studies for serum and plasma IL-6 levels (P = 0.00044 and P = 0.01445, respectively). In summary, the meta-analysis and meta-regression confirmed that, compared to healthy controls, individuals with OSAS (children and adults) had higher serum/plasma IL-6 levels.

Decompressive craniotomy (DC) is a known risk factor for the development of posttraumatic hydrocephalus (PTH) in the patients with traumatic brain injury (TBI). Herein, the present study reported the development of PTH requiring ventriculoperitoneal (VP) shunt after DC for TBI. Four databases (PubMed, Web of Science, Scopus, and Cochrane Library) were searched from 1983 to April 2018. The studies evaluating the prevalence of PTH requiring VP shunt after DC in the patients with TBIwere selected without language restriction. A random-effects meta-analysis using event rate (ER) and 95% confidence intervals(CIs), was runby RevMan5.3 software. Out of 355 studies obtained from the databases, 25 studies were included and analyzed in the meta-analysis. The studies included 2402 patients undergoing DC for TBI, 354 of whohad PTH. The pooled ER of hydrocephalus in the patients undergoing DC for TBI was 17.7% [95%CI: 13.2 to 23.4%; P<0.001]. In addition, the pooled analysis showed that ER of hydrocephalus was 13% in adults [95%CI: 9 to 18.5%; P<0.001] and 37.6% in children [95%CI: 27.79 to 48.7%; P=0.029; I2=0%]. The present study demonstrated that DC after TBI was associated with the development of PTH, especially in children compared to adults.

Aim of the study This meta-analysis evaluated serum interleukin-6 (IL-6) levels in hepatocellular carcinoma (HCC) patients compared with healthy controls and hepatitis and cirrhotic patients. Material and methods The three databases PubMed, Scopus, and Web of Science were searched for...