Predicting Persistent Orofacial Pain: The Role of Illness Perceptions, Anxiety, and Depression.

Introduction: Persistent orofacial pain (POFP) can be caused by a range of conditions affecting the mouth and face and is often associated with significant disability. Biopsychosocial factors are known to be important predictors and have not yet been fully explored in this population. Objectives: This study aimed to explore whether illness perceptions and psychological distress (anxiety and depression) could predict long-term outcome in a community-based sample of patients receiving routine care for POFP. Methods: A longitudinal cohort design study assessed 198 patients recruited from primary or secondary health care settings on 5 separate occasions over a 2-y period. Outcome was measured by the Graded Chronic Pain Scale and dichotomized into good or poor outcome categories. Independent variables included subscale scores of the psychometrically shortened Illness Perception Questionnaire and the Patient Health Questionnaire-4 (PHQ-4, assessing anxiety and depressive symptomatology). Logistic regressions were performed to test whether scores on each subscale would be associated with different outcomes for patients at 12 and 24 mo and overall. Results: Beliefs about consequences predicted outcome category (good vs. poor) above and beyond other illness perception subscales, anxiety, and depressive symptomatology (z = 3.78; P < 0.000; odds ratio [OR], 3.05; 95% confidence interval [CI], 1.71-5.43). Both depressive symptomatology, measured by the PHQ-2 (P = 0.001; OR, 4.06; 95% CI, 1.74-9.52), and psychological distress (mixed anxiety and depression; P = 0.029; OR, 2.88; 95% CI, 1.12-7.41), measured by the PHQ-4, were also predictive of poor outcome, but these effects were no longer significant once measures of illness perceptions were added. Conclusion: Beliefs about the consequences of POFP are important predictors of outcome independent of other variables and can easily and briefly be included in assessments to inform management decisions. Knowledge Transfer Statement: The results of this study are relevant because they will allow clinicians to consider the use of brief and easy-to-administer self-report measures to identify POFP patients at higher risk of poor outcome so that management can be planned accordingly.