Cannabis use and the risk of periodontitis: A two-sample Mendelian randomization study

Aim This study aimed to leverage human genetic data to investigate whether cannabis use causally affects periodontitis. Materials and Methods Data were obtained from summary statistics of genome-wide association studies of lifetime cannabis use (N = 184,765), cannabis use disorder (17,068 cases; 357,219 controls), and periodontitis (17,353 cases; 28,210 controls). We performed two-sample Mendelian randomization (MR) analysis using 6 genetic variants as instrumental variables for lifetime cannabis use and 11 variants as instruments for cannabis use disorder to estimate associations with periodontitis. Results There was no evidence for an association between genetic liability for lifetime cannabis use or cannabis use disorder with periodontitis. The estimates from the primary analyses were supported in multivariable MR analysis, which considered potential pleiotropic pathways and in weak instrument analyses. Conclusions This study provides little evidence to support a detrimental effect of genetic liability for cannabis use on periodontal health.