CRP and periodontitis: Genetically proxied IL-6 signaling downregulation was associated with a reduced odds of periodontitis (OR per 1-unit decrement in log-CRP levels = 0.81; 95% confidence interval (CI): [0.66; 0.99]; P = 0.0497) in the inverse variance weighted (multiplicative random effects) regression (Table 2, Figure 3).