Abstract
INTRODUCTION: Recent evidence suggests the relationship between periodontitis and systemic inflammation, which complete blood count can assess (CBC)-derived biomarkers such as neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR). We conducted this meta-analysis to evaluate the levels of NLR and PLR of patients with periodontitis compared to those of healthy controls. METHODS: Web of Science, PubMed, ProQuest, Scopus, and Open Grey were searched for studies published before October 20, 2024, without any limitation on date and language; then, using the random-effects model, we reported a standardized mean difference (SMD) with a 95% confidence interval (CI). In order to assess the quality of publications, we used the Newcastle-Ottawa scale (NOS). Our study was registered in PROSPERO (CRD42023475214). RESULTS: Overall, 11 articles were included in the analysis. We found that patients with periodontitis had elevated levels of NLR compared to healthy controls (SMD = 0.30, 95% CI 0.08-0.52, p = 0.007) In the subgroup analysis according to race, patients with periodontitis had elevated levels of NLR compared to healthy controls in among East Asian patients (SMD = 0.35, 95% CI 0.15-0.55, p = 0.001), but not among Turkish (SMD = 0.15, 95% CI - 0.30-0.61, p = 0.50) and Indian (SMD = 0.38, 95% CI - 0.17-0.94, p = 0.18) patients. In addition, PLR level was not different among patients with periodontitis and healthy controls (SMD = 0.06, 95% CI - 0.71-0.83, p = 0.87). CONCLUSIONS: The findings of our investigation, which indicate higher NLR levels in periodontitis patients, show that immune dysregulation plays a role in the etiology of the disease.