Associarion Between Plasma Homocysteine Level And Non Alcoholic Fatty Liver Disease:A Meta-analysis

Background and ObjectiveNon Alcoholic Fatty Liver Disease(NAFLD)has become the most common liver disease in the world and the research and treatment of NAFLD are also receiving more and more attention.With the deepening research of NAFLD,many studies found that homocysteine and NAFLD are closely related,but the results of each study vary.Therefore,this study aims to comprehensively assess the correlation between plasma homocysteine(Hcy)levels and NAFLD by meta-analysis,and investigate the relationship between the plasma homocysteine levels and the level of serum folate and vitamin B12.MethodsComputer retrieval was performed for relevant literature about the levels of plasma homocysteine or folate,vitamin B12 and NAFLD in Pumbed,Cochrane Library,Wanfang Resource Database,CNKI,China Dissertation Database and VIP Journal Database.According to inclusion and exclusion criteria,the eligible documents and their data were extracted.Statistic was merged and analyzed with Review Manager 5.3 and Statal 2.0 software.Results1.A total of 21 studies met inclusion criteria.Among them,there are 20 articles about the correlation between plasma Hey level and NAFLD,and 13 articles about the correlation between serum folate,vitamin B12 and NAFLD respectively.2.Plasma homocysteine level used as evaluation index,compared the NAFLD group and the control group:n=20,the standard mean difference(SMD)was 0.67,95%CI(0.54,0.79).According to the region,detection method and diagnostic method,the subgroups were analyzed respectively.The results suggested that plasma homocysteine levels in all subgroups of patients with NAFLD were higher than those in normal control group.Besides,compared the non alcoholic fatty liver(NAFL)group with the control group:n=7,the SMD was 0.68,95%CI(0.26,1.10).Compared the non alcoholic steatohepatitis(NASH)group with the control group:n=9,the SMD was 0.75,95%CI(0.34,1.17).All comparison between two groups have significantly different.3.The average value of folate used as evaluation index,compared NAFLD and the control group:n=13,SMD was-0.14,95%CI(-0.35,0.08),the difference was not statistically significant(P>0.05).Subgroup analysis was conducted according to the region,detection method and diagnostic method of the patients.The results indicated that the serum folate levels in NAFLD patients in each subgroup were not significantly different from those in normal controls.4.The average value of vitamin B12 used as evaluation index,compared NAFLD and the control group:n=13,SMD was0.08,95%CI(-0.28,0.45),the difference was not statistically significant(P>0.05).In the subgroup analysis,the level of serum vitamin B12 in NAFLD patients was higher than that in the normal population in America,while the level of serum vitamin B12 in Asian NAFLD patients was lower than that in the normal population(P<0.05).Conclusion1.Plasma homocysteine level was higher in NAFLD patients as compared with the healthy controls,which can be used as one of makers for diagnosis of NAFLD,and high plasma homocysteine level may play an important role in the pathogenesis of NAFLD.2.Serum folate and vitamin B12 levels in NAFLD patients and normal population had no significant difference,but the vitamin B12 levels may be affected by regional differences.3.In patients with NAFLD,folate and vitamin B12 levels are not the major cause of the increase in plasma homocysteine levels.