Cortisol and periodontitis: Prospective observational and Mendelian randomization studies

Area of Science:

• Endocrinology
• Periodontology
• Human Genetics

Background:

• Cortisol, a stress hormone, has known obesogenic, hyperglycemic, and immunomodulating effects.
• Previous research suggests a link between cortisol and periodontitis, but human causal evidence is limited.

Purpose of the Study:

• To investigate the potential causal association between cortisol levels and periodontitis in humans.
• To triangulate findings from prospective observational and Mendelian randomization (MR) analyses.

Main Methods:

• Prospective observational study using pooled data from 3,388 participants in the Study of Health in Pomerania (SHIP) project.
• Two-sample Mendelian randomization (MR) analysis using genetic data from 17,353 periodontitis cases and 28,210 controls.
• Propensity score weighting and multiple imputation were used to adjust for confounding and selection bias in the observational analysis.

Main Results:

• Observational analysis: Cortisol levels were positively associated with clinical attachment level (CAL) and bleeding on probing, but not probing pocket depth.
• Mendelian randomization analysis: Genetically proxied plasma morning cortisol levels were not associated with periodontitis.
• Discrepancy between observational and genetic findings suggests potential confounding or reverse causation in observational data.

Conclusions:

• While observational data suggest a prospective association between cortisol and periodontitis markers, Mendelian randomization provides no evidence for a causal role of cortisol.
• The findings cast doubt on cortisol-related pathways contributing to periodontitis pathology.
• Further research is needed to clarify the complex relationship between stress hormones and periodontal disease.