Predictors for future clinically significant pain in patients with temporomandibular disorder: A prospective cohort study

Background: Up to 30% of patients with temporomandibular disorder (TMD) run the risk of progressing to chronic pain with significant disability. This prospective cohort study assessed the effects of baseline pain and general health and psychosocial factors on the presence of clinically significant pain in patients with TMD pain at 1 year after initial consultation. Methods: 263 primary care patients with TMD pain were included. At the baseline, patients completed a pain questionnaire including a wide range of putative prognostic factors, which were assessed using validated self-report scales. The outcome, clinically significant pain at 1 year was defined as grades IV and III and grades II and I with any disability points on the Graded Chronic Pain Scale (GCPS). Multivariable logistic regression was used to study the association between the outcome and each predictor variable. Results: At 1 year, 26.9% of the patients reported clinically significant pain. The number of previous healthcare visits (OR 1.19, 95% CI 1.021.39), pain intensity/dysfunction of other pain conditions (OR 1.35, 95% CI 1.07-1.69), the number of other pain conditions (OR 1.31, 95% CI 0.98-1.74), the number of disability days (OR 1.05, 95% CI 1.00-1.12), and perceived ability to control pain (OR 0.79, 95% CI 0.61-1.01) were associated with the outcome. The area under the curve (AUC) for the whole model indicated acceptable discriminative ability (0.74, 95% CI 0.66-0.82). Conclusions: Reporting several previous healthcare visits and comorbid pains with high pain intensity and disability signal increased risk for poor prognosis of TMD pain. Significance: About 27% of primary care TMD pain patients reported clinically significant pain at 1 year after initial consultation. Reporting several previous healthcare visits and comorbid pains with high pain intensity and disability were associated with poor prognosis of TMD pain.