Association between components of metabolic syndrome and periodontitis: a systematic review and meta-analysis

Objectives To evaluate the role of metabolic syndrome (MetS) components in the association with periodontitis (PE) (#CRD42020218310). Materials and methods A systematic electronic search was performed in PUBMED, Scielo and Lilacs databases up to April 2022. Cross-sectional, case-control, and cohort studies presenting data on the association between MetS and PE in the adult and elderly populations were included. A random effect meta-analysis was performed to determine association effect estimates. Results interpretation followed the assessment of methodological quality (Joana Briggs Institute tool) together with the certainty of evidence (GRADE approach). Results This review included 52 studies, totalling 140,434 participants, and 38 studies were meta-analyzed. Association between PE and MetS was observed (ORadj from 1.27 to 1.90; PRajd = 1.19; RRadj from 1.10 to 1.37) (low and very low certainty of evidence). Hyperglycaemia (OR = 1.18), HDL (OR = 1.16), obesity (OR = 1.08), and hypertension (OR = 1.11) were associated with PE, except triglycerides (low and very low certainty of evidence). There was a dose-response gradient between the number of MetS components and PE, with a gradual increase in the effect magnitude for 1 (OR = 1.14), 2 (OR = 1.52), 3 or more (OR = 1.79), and 4 or 5 components (OR = 2.02) (low to high certainty of evidence). Conclusions MetS was associated with PE, with a dose-response gradient between the number of MetS components and the occurrence of PE, with an increasing effect magnitude according to an increasing number of components.