Prevalence, Course, and Associated Factors of Pain in the Temporomandibular Joint in Early Rheumatoid Arthritis: Results of a Longitudinal Cohort Study.

AIMS: To assess the prevalence, 3-year course, and associated factors of temporomandibular joint (TMJ) pain in patients with newly diagnosed rheumatoid arthritis (RA).

METHODS

A total of 264 patients with newly diagnosed RA were included. Patients were assessed after 3 months, 6 months, 9 months, 1 year, 1.5 years, 2 years, and 3 years. TMJ pain was scored by manual palpation, and the prevalence of TMJ pain was calculated at baseline and at all seven follow-up intervals during 3 years. Factors assessed for a potential association with TMJ pain at baseline included: demographic factors (gender and age), disease-related factors (symptom duration, rheumatoid factor [RF], anti-cyclic citrullinated protein [anti-CCP], C-reactive protein [CRP], and Disease Activity Score 28 [DAS28]), and functional factors (Health Assessment Questionnaire [HAQ] and European Quality of Life 5 Dimensions Questionnaire [EQ5D]-anxiety/depression). A stepwise logistic regression model was used to determine factors associated with TMJ pain in patients with RA.

RESULTS

The prevalence of TMJ pain in patients with RA was 10.6% at baseline, which decreased to 3.6% in the first year after inclusion and remained stable thereafter. Disease activity as determined by the DAS28 was significantly associated with TMJ pain (odds ratio [OR] = 1.51; 95% confidence interval [95% CI] = 1.12-2.05; P = .009) at baseline. A second logistic regression analysis was performed with the following variables of the DAS28: erythrocyte sedimentation rate (ESR), tender joint count, swollen joint count, and global health. Tender joint count (OR = 1.06; 95% CI = 1.01-1.12; P = .03) and global health (OR = 1.02; 95% CI = 1.00-1.03; P = .03) were significantly associated with TMJ pain at baseline. The remaining factors included in the analysis were not significantly associated with TMJ pain at baseline.

CONCLUSION

The prevalence of TMJ pain in patients with newly diagnosed RA is approximately 10% and decreases during follow-up, especially in the first year. Disease activity is a risk factor for TMJ pain in patients with newly diagnosed RA.