Objective: To assess the effects of thymosin alpha1 to enhance immunity and on the prognosis of sepsis.
Methods: The database from CNKI (1994-2008.10), CBM (1978-2008.10), VIP (1989-2008.10), Wanfang Database (1997-2008.10), PubMed (1966-2008.10), Cochrane Library (Issue 3, 2008), EMBASE(1974-2008.10) and SCI (1974-2008.10) were retrieved using the key words "sepsis OR septicemia OR blood poisoning OR systemic inflammatory response syndrome OR multiple organ failure OR multiple organ dysfunction syndrome" AND "thymosin * OR zadaxin OR thymalfasin". Also related journals were reviewed. Randomized and q-randomized trials of thymosin for sepsis were included. Two investigators were engaged to extract the data independently and evaluate the quality of the included studies with Handbook 4.2.6 recommended standard, and analyzed data with Cochrane Collaboration's RevMan 4.2.10.
Results: Five randomized controlled trials (198 patients) were included. Meta-analysis showed that thymosin alpha1 may raise the level of CD4(+)T lymphocytes [WMD=6.24, 95% confidence interval (CI) 1.12 to 11.36] and the ratio of CD4(+)/CD8(+)(WMD=0.14, 95%CI 0.03 to 0.25, P=0.01), improve the immune state of the patients. Also, thymosin alpha1 therapy decreased the score of acute physiology and chronic health evaluation II (APACHE II), WMD=3.82, 95%CI 2.36 to 5.28 , P<0.001 ) and the mechanical ventilation days (WMD=-4.17, 95%CI-7.00 to -1.34, P=0.004 ). Furthermore, thymosin alpha1 therapy shortened the duration of intensive care unit (ICU) stay (WMD=-4.87, 95%CI -8.17 to -1.60, P=0.004).
Conclusion: The current evidence shows that thymosin alpha1 improves the immuno-suppression and helps recovery of the patient from disease. However not enough evidence is found in decreasing the mortality. Further randomized controlled trials should include the dosage, duration of the treatment and timing of using thymosin alpha1.