RESUMO
Previous studies have demonstrated a strong association between primary headaches (HAs) and temporomandibular disorders (TMDs), specifically the myofascial pain subtype of TMD (MP TMD). The role of anxiety and depression in presentation and maintenance of MP TMD and migraine is previously demonstrated. Therefore, the objective of the current study was to evaluate the modification effect of anxiety and depression on the possible association of MP TMD and migraine. Methods: In this retrospective case–control study, individuals between 15 and 45 years old who were diagnosed with migraine HA according to the international classification of headache disorder-II (ICHD-II) were selected as case subjects (n = 65). Non-HA control subjects were matched by sex and age (n = 63). Research diagnostic criteria (RDC/TMD) (Axis I) was used to diagnose patients with MP TMD; other subtypes of RDC/TMD Axis I were excluded from the study. Subjects' anxiety and depression were screened using Persian version of Hospital Anxiety and Depression Scale-14. Chi-square and Mantel–Haenszel tests were used to analyze the data. P < 0.05 was considered statistically significant. Results: A significant association was found between migraine and MP TMD so that subjects with MP TMD had a five times chance of developing HA (P < 0.001). Further analysis using stratification method revealed that anxiety and depression have a modification effect in the association of MP TMD and HA and MP TMD patients with anxiety or depression had more chance of developing migraine HA (P = 0.003). Conclusion: Association between HA and TMD was observed in this study. Besides, we depicted that anxiety and depression interact in this association so that patients who did not have anxiety or depression did not demonstrate an association between TMD and HA. We suggest further studies to confirm the modifying effects of anxiety and depression.