Association of hyperglycaemia and periodontitis: an updated systematic review and meta-analysis

Purpose The aim of this updated systematic review and meta-analysis was the association between hyperglycemia and periodontitis. Methods We searched PubMed/MEDLINE, Web of Science, and Scopus until March 2021. The key search words were based on "periodontitis" and "hyperglycemia." We included cohort, case-control, and cross-sectional studies, restricted to publications in English. The quality assessment of included studies and data extraction were done by two independent reviewers. Meta-analysis was performed for cross-sectional studies using the random-effects model. Results The literature search yielded 340 studies, and finally, 19 and 11 studies were included in systematic review and meta-analysis, respectively. The total sample size of the eligible studies in the meta-analysis was 38,896 participants, of whom 33% were male with a mean age of 51.20 +/- 14.0 years. According to a random-effect meta-analysis in cross-sectional studies, the pooled odds ratio (OR) for the association between hyperglycemia and periodontal indices was statistically significant (OR: 1.50, 95%CI: 1.11, 1.90). There was evidence of publication bias (coefficient: - 3.53, p-value = 0.014) which, after imputing missing studies, the pooled OR of the association between hyperglycemia and periodontitis change to 1.55 (95%CI: 1.20, 1.90). Conclusion Results of the present study show that hyperglycemia was positively associated with periodontitis. However, more cohort and prospective longitudinal studies should be conducted to find the exact association. Overall, it seems the management of hyperglycemia could be considered as a preventive strategy for periodontitis.