Probiotics And Chronic Diseases:A Bibliometric Analysis And Systematic Review Of Systematic Reviews

Background:Chronic disease is one of the major global health issues nowadays.Specially non communicable Chronic diseases such as diabetes,cancer and heart diseases associated with poor short term and long term complications are the most common causes of morbidity and mortality of the patients.On the other hand,probiotics are playing very important role in these diseases.Research on these chronic diseases and probiotics is increasing with a lot of publications.However the quality and quantity of research on chronic diseases and probiotics need to be understood clearly.This study aims to provide a bibliometric overview of research on probiotics and chronic diseases on the first part and to summarize the glycemic effects of probiotics on type 2diabetes systematically on the second part.Methods:In the first part for bibliometric analysis,Web of Science Core Collection?WoSCC?was used to extract relevant research on probiotics and chronic disease published from 1994 to 2018.The key bibliometric indicators such as trends of annual publications,top 10 authors,countries,journals and institutions,citation analysis of articles,co-occurrence of keywords,top 100 cited articles etc.were presented in this study.Analyses were performed using Web of Science,VOS-viewer and Microsoft Excel.For the second part,electronic search using four electronic databases such as PubMed,Cochrane Library,Web of Science and Scopus was performed until January 31^st 2019.Papers were included if they reported a systematic review of the glycemic effects of probiotics on type 2 diabetes.The methodological quality of the included reviews was assessed by using R-AMSTAR.Eight reviews were included for meta-analysis.As these reviews were themselves meta-analysis,so to avoid the repetition of same data and to get high statistical power,each review was unpicked and data were extracted from the individual study for meta-analysis.The outcomes of interest of this review were fasting blood glucose?FBG?,glycosylated hemoglobin?HbA1c?,blood insulin level and Homeostasis Model Assessment-Insulin Resistance?HOMA-IR?.Mean differences?MD?between control groups and intervention?probiotics?groups for all outcomes were pooled using fixed or random-effect model.I²was used to assess the statistical heterogeneity.Results:For bibliometric analysis a total of 5497 publications related to probiotics and chronic diseases published between1994 to 2018 are found.USA is found to be the most productive country followed by People's Republic of China and Italy in second and third position respectively.Harvard University in USA ranked first in publishing documents in probiotics and chronic disease with 65 publications.Among the top 10most active journals Plos One has published largest number of documents?N=128?.Nutrition dietetics is the most popular research area with 698 publications.“Probiotics”,“colorectal cancer”,“inflammation”and“bacteria”are the most frequently occurred keywords in this research documents.The meta-analysis on the second part of the study showed probiotics consumption has significantly reduced FBG level?n=16 studies;SMD=-0.516;95%CI=-0.735 to-0.298;P<0.001?;with significant moderate heterogeneity?I²=61.5%;P=0.001?.Subgroup analysis based on the number of bacterial species revealed that the products containing more than one bacterial species and containing only 1 species both could reduce FBG significantly with SMD=-0.60?P=0.001?and SMD=-0.488?P=.002?respectively.Subgroup analysis according to the duration of intervention did not find any significant result in any subgroup.Probiotics supplementation had no significant effect on HbA1c level?n=10 studies;SMD=-0.037;95%CI=-0.507 to 0.434;P=0.878;I²=87.4%;P<0.001?and insulin concentration?n=7 studies;SMD=-0.412;95%CI=-1.260 to 0.436;P=0.341?.Subgroup analysis also didn't reveal any significant change on them.But probiotic consumption was found to reduce HOMA-IR level?n=7 studies;SMD=-0.912;95%CI=-1.757 to-0.067;P=0.034?in type 2 diabetic patients significantly.There was high inter-study heterogeneity with the findings?I²=94.3%;P<0.001?.Conclusion:Research on probiotics and chronic disease have shown that the USA is the top most country in publications and collaborations with other countries.As chronic disease is a global problem,so besides the USA,other countries should give greater attention on this issue.About probiotic supplementation on type 2 diabetes we can conclude that it can be used as an adjunct therapy as our result showed its beneficial glycemic effects on type 2 diabetic patients.