Hematological biomarkers of systemic inflammation in predicting long-term treatment response of temporomandibular disorders

Abstract Background Chronic systemic inflammation has been proposed as the underlying mechanism of pain chronicity in several pain conditions. In spite of the growing evidence supporting the role of systemic inflammatory markers as a diagnostic tool, their role has not been analyzed in a well-defined group of temporomandibular disorders (TMD) patients until now. This study aimed to investigate the association between various clinical features and comorbidity levels of TMD in relation to hematological markers and seek its association with long-term treatment response. Methods Clinical features and hematological indices including those for systemic inflammation were assessed in TMD patients (n = 154). Examinations were re-done after 6 months of conservative treatment. Patients were divided into pain improved and unimproved groups based on ≥ 2 numeric rating scale improvement in pain intensity at 6 months for final analysis. Results The portion of patients with low lymphocyte-to-monocyte ratio (p = 0.026), total protein (p = 0.014), hemoglobin (p = 0.040), and mean corpuscular hemoglobin concentration (p = 0.042) values showed significant differences according to prognosis groups. Low hemoglobin levels were significantly associated with unfavorable response to long-term treatment (β = 1.706, p = 0.018). High pre-treatment pain intensity (β=-0.682, p