Relationship between Periodontitis and Pre-Eclampsia: A Meta-Analysis

Background: Studies have suggested controversial results regarding a possible association between pre-eclampsia (PE) and periodontal disease (PD) and no meta-analysis has been performed to clarify this issue. Methods: A literature search of electronic databases was performed for articles published through March 24, 2013, followed by a manual search of several dental and medical journals. The meta-analysis was conducted according to the recommendations of the Cochrane Collaboration and PRISMA. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Heterogeneity was assessed with the chi(2)-based Cochran Q test and I-2 statistic. The level of significance was set at P<0.05. Results: Fifteen studies were included, including three cohort and 12 case-control studies. A positive association was found between PE and PD (OR 2.17, 95% CI 1.38-3.41, P = 0.0008). However, a high and significant heterogeneity was found (chi(2) = 62.42, P<0.00001, I-2 = 75%). In most cases, subgroup analysis had low power to detect significant differences between PE and non-PE groups. Conclusion: Based on the findings of the meta-analysis, PD appears to be a possible risk factor for PE. However, given the important differences in the definitions and diagnoses of PD and PE among the studies, as well as their lack of good methodological quality, future trials are needed to confirm the results of the present meta-analysis.