Fibromyalgia and periodontitis: Bidirectional associations in population-based 15-year retrospective cohorts.

Abstract

To determine the bidirectional link between periodontitis and fibromyalgia. In this cohort study, 196,428 periodontitis patients and 196,428 propensity score-matched non-periodontitis controls were enrolled. A Cox proportional hazard model was utilized to estimate the risk of fibromyalgia and survival analysis was adopted to assess the time-dependent effect of periodontitis on fibromyalgia. Subgroup analyses stratified by age, sex, and tracking period were conducted to identify susceptible populations. A parallel and symmetrical cohort that recruited 141,439 fibromyalgia patients and 141,439 propensity score-matched non-fibromyalgia controls ascertained the inverse effect of fibromyalgia on incident periodontitis. Patients with periodontitis were more likely to develop fibromyalgia than non-periodontitis controls (HR=1.42, 95% CI=1.39-1.44, P<0.001), which persisted in the survival analysis (log-rank test P<0.0001). This effect was significant in both sexes and all age subgroups, and was particularly evident in males (HR=1.52, 95% CI=1.48-1.56, P<0.001) and younger periodontitis patients (HR=1.55, 95% CI=1.50-1.60, P<0.001). Fibromyalgia patients who never had periodontitis presented with greater risk for periodontitis over time (HR=1.43, 95% CI=1.40 - 1.45, P<0.001; log-rank test P<0.0001). Patients of both sexes and all age subgroups with periodontitis presented with a greater risk of fibromyalgia. Subgroups that were the most susceptible to periodontitis-associated fibromyalgia were periodontitis patients that were males and below 30 years old. Risks of periodontitis were also greater in fibromyalgia patients who never had periodontitis.