Association Between Periodontitis and Gestational Diabetes Mellitus: Systematic Review and Meta-Analysis.

BACKGROUND: To the best of the authors' knowledge, there is no systematic review of the potential association between periodontitis and gestational diabetes mellitus (GDM) in the current literature. The aim of the present systematic review and meta-analysis is to search for scientific evidence regarding the association between periodontitis and GDM. METHODS: The present study was conducted in accordance with the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and registered (CRD2014010728) with PROSPERO (International prospective register for systematic reviews, University of York, York, UK). A search was conducted in three electronic databases without restrictions regarding language or date of publication. From 190 studies selected, 15 underwent full-text analysis. Eight studies were eligible (five cross-sectional and three case-control studies), and seven were entered in the meta-analysis. Meta-analysis was performed with tests for sensitivity and statistical heterogeneity. Summary effect measures were calculated by odds ratio (OR) and 95% confidence interval (CI). RESULTS: There was a significant association between periodontitis and GDM in the meta-analyses of four cross-sectional studies (OR 1.67, 95% CI 1.20 to 2.32) and two case-control studies (OR 2.66, 95% CI 1.52 to 4.65). However, sensitivity tests for case-control studies showed a lack of consistency in data; when including one case-control study, the significance was null (meta-analysis of three case-control studies: OR 1.69, 95% CI 0.68 to 4.21). CONCLUSIONS: There was substantial clinical, methodologic, and statistical heterogeneity among the studies. The scientific evidence cannot affirm a positive association between periodontitis and GDM. Future studies with different designs in distinct populations should be conducted to investigate this association.