Lack of bidirectional associations between gastroesophageal reflux disease and periodontitis: a systematic review and meta-analysis.

The bidirectional relationship between gastroesophageal reflux disease (GERD) and periodontitis (PD), particularly the temporal directionality, remains unclear. A systematic review and meta-analysis were conducted to evaluate bidirectional associations between GERD and PD. Three databases (PubMed, Embase, and Cochrane Library) were systematically searched from inception to December 1, 2024. Risk estimates from individual studies were pooled using random-effects models. Five studies assessed the risk of PD in patients with GERD, while three studies evaluated the risk of GERD in patients with PD. The overall analysis suggested an increased risk of PD among patients with GERD (odds ratio [OR] = 1.27; 95% confidence interval [CI]: 1.02-1.57; p = 0.029; I2 = 96.5%). However, sensitivity analyses, limited to cohort studies (OR = 1.15; 95% CI: 0.93-1.42; P = 0.05; I2 = 96.9%) and subgroup analyses, did not support this finding. Similarly, PD patients did not exhibit a higher risk of GERD (OR = 1.19; 95% CI: 0.90-1.57; P = 0.223; I2 = 94.3%). The present study could not confirm any bidirectional associations between GERD and PD. Further high-quality longitudinal studies are required to validate these findings.