Previous Pain and Stress Experiences Predict Persistent Jaw Muscle Pain

The aim of the present study was to assess possible predictive factors for persistent myofascial pain (MFP) diagnosed over a 1-year period in a non-patient working population. Objectives: All 30-to 55-year-old employees of the Finnish Broadcasting Company (YLE) whose current employment had lasted at least five years in the Helsinki area (n=1784) were invited. Of these, 1339 (75%) completed a standardized questionnaire. Clinical examinations were performed on 241 randomly selected participants (18%) at baseline and, eventually, on 211 subjects who participated also in the 1-year follow-up examinations (88%). The mean age of these 211 employees (females 53%) was 46 years (SD 6) in both genders. Methods: Studied prognostic factors were gathered from the baseline questionnaire (Occupational Stress Questionnaire) which included demographic items, pain perceptions, and biopsychosocial questions. Clinical examinations were performed according to the Finnish translation of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Results: Altogether 7% had persistent myofascial pain. Studied age groups were not significantly associated with MFP, although the youngest age group was relatively larger in those with persistent MFP. In the bivariate analyses, those with previous frequent orofacial pain experience (p=0.004) and those with severe stress (p=0.037) were significantly more often diagnosed to have persistent MFP. A slight association was seen with previous frequent neck pain experience and persistent MFP (NS). Logistic regression also revealed that previous frequent orofacial pain experience (P=0.016) and perceived severe stress (P=0.049) were independently significantly associated with the probability of persistent myofascial pain. Conclusions: Previous frequent orofacial pain experience and perceived stress may predict persistent myofascial pain in the jaw muscles.