Association between metabolic syndrome and tooth loss: A systematic review and meta-analysis

The authors conducted a systematic review and meta-analysis to verify the existence and level of scientific evidence concerning the association between metabolic syndrome (MetS), as the main exposure, and tooth loss (TL), as the outcome.

Through electronic databases and partially through gray literature, the authors identified observational studies in adults. The authors used no date or language restrictions. The authors evaluated the studies' methodological quality by using the Newcastle-Ottawa Scale. The authors conducted a random-effects model meta-analysis. The authors assessed the quality of evidence by using the Grading of Recommendations Assessment, Development and Evaluation criteria.

Twelve studies met the eligibility criteria, and 9 were retained for the meta-analysis. Most were cross-sectional studies with good methodological quality. Participants with MetS had fewer teeth (standardized mean difference, -2.77; 95% confidence interval, -4.56 to -0.98) and an increased likelihood of lacking functional dentition (odds ratio, 2.37; 95% confidence interval, 1.89 to 2.96) than did those without MetS. The overall quality of evidence was very low.

Better-conducted longitudinal studies are necessary to establish a causal relationship between MetS and TL to inform the best strategies to prevent TL in populations with MetS.