title: Prevalence of Oral Lichen Planus in Diabetes Mellitus: a Meta-Analysis Study.
abstract: BACKGROUND
  Oral lichen planus (OLP) is associated with various other systemic conditions such as hypertension, diabetes mellitus (DM). This study evaluated the prevalence of OLP in DM patients compared with non-diabetic control subjects in a meta-analysis study.
  
  
  METHODS
  In this study from January 1973 to August 2016, we searched the studies in Web of Science, Medline/PubMed, Scopus, Science direct, SID (Scientific Information Database), Cochrane and Embase databases. Strategy search was the Medical Subject Heading (MeSH) term oral lichen planus or oral mucosa combined with diabetes in PubMed and this search in other databases. Heterogeneity between estimates was evaluated by the Q and I2statistic. Also, publication bias was assessed through funnel plot analysis with the Kendall's and Egger's tests.
  
  
  RESULTS
  From 831 studies were identified with different search strategies, 11 studies met the criteria to be included in meta-analysis (11 case-control studies). The overall prevalence of OLP in 11 studies with 4937 DM patients and 3698 control subjectswas 1.5% and 0.75%, respectively. In this meta-analysis, the OR in prevalence of OLP in DM patients compared with control subjects was 1.584 (95%CI1.013-2.477; P=0.044) with a low level of heterogeneity (I2= 0%) that the result showed the prevalence of OLP in DM patients is significantly more than control subjects.
  
  
  CONCLUSIONS
  This meta-analysis study showed an association between OLP with DM, whereas this association was no significant in previous studies, it was probably because different selecting of age, sex, type of DM, medications and criteria. Totally, the meta-analysis showed the risk of OLP in DM was higher compared with control subjects.
authors.affiliation: Department of Oral Medicine, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah, Iran.
authors.forename: Hamid Reza
authors.initials: HR
authors.lastname: Mozaffari
authors.affiliation: Department of Endodontics, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah, Iran.
authors.forename: Roohollah
authors.initials: R
authors.lastname: Sharifi
authors.affiliation: Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran; Students Research Committee, Kermanshah University of Medical Sciences, Kermanshah, Iran.
authors.forename: Masoud
authors.initials: M
authors.lastname: Sadeghi
keywords: Diabetes mellitus; Meta-analysis study; Oral lichen planus