Lloyd Mancl

Mediators, moderators, and predictors of therapeutic change in cognitive-behavioral therapy for chronic pain

Abstract Although cognitive–behavioral therapies (CBT) have been demonstrated to be effective for a variety of chronic pain problems, patients vary in their response and little is known about patient characteristics that predict or moderate treatment effects. Furthermore, although cognitive–behavioral theory posits that changes in patient beliefs and coping mediate the effects of CBT on patient outcomes, little research has systematically tested this. Therefore, we examined mediators, moderators, and predictors of treatment effects in a randomized controlled trial of CBT for chronic temporomandibular disorder (TMD) pain. Pre‐ to post‐treatment changes in pain beliefs (control over pain, disability, and pain signals harm), catastrophizing, and self‐efficacy for managing pain mediated the effects of CBT on pain, activity interference, and jaw use limitations at one year. In individual mediator analyses, change in perceived pain control was the mediator that explained the greatest proportion of the total treatment effect on each outcome. Analyzing the mediators as a group, self‐efficacy had unique mediating effects beyond those of control and the other mediators. Patients who reported more pain sites, depressive symptoms, non‐specific physical problems, rumination, catastrophizing, and stress before treatment had higher activity interference at one year. The effects of CBT generally did not vary according to patient baseline characteristics, suggesting that all patients potentially may be helped by this therapy. The results provide further support for cognitive–behavioral models of chronic pain and point to the potential benefits of interventions to modify specific pain‐related beliefs in CBT and in other health care encounters.

Changes in temporomandibular pain and other symptoms across the menstrual cycle

&NA; The objective of this study was to assess changes in levels of clinical temporomandibular (TMD) pain in relation to phases of the menstrual cycle. TMD cases were 35 women not using oral contraceptives (OCs); 35 women using OCs; and 21 men. Controls were 35 normally cycling women without TMD or other chronic pains. Subjects kept daily diaries over three menstrual cycles, reporting average and worst pain, general and premenstrual symptoms. Data were subject‐centered and de‐trended using the residuals from a random‐effects linear regression model. To test for cyclic variation, cycles were standardized to 28 days and data were grouped into 9 periods/cycle (Days 1–3, 4–6,…, 22–24, 25–28). Overall levels of average pain, worst pain and symptoms did not differ across TMD subject groups. For worst pain, multivariate analysis of variance revealed a statistically significant difference across 3‐day periods for normally cycling women with TMD (P=0.011) and for women using OCs (P=0.017). In both groups, TMD pain levels rose toward the end of the cycle and peaked during menstruation. In women not using OCs, there was a secondary pain peak at Days 13–15, around the time of ovulation. This peak was not seen in women using OCs. There was no statistically significant difference over time periods for men (P=0.94). Similar patterns were found for average pain, as well as PMS symptoms and general somatic symptoms. These results suggest that TMD pain in women is highest at times of lowest estrogen, but rapid estrogen change may also be associated with increased pain.

Origins of childhood dental fear

This study explored Rachmans theory of fear acquisition applied to fear of the dentist in a large sample of low income American primary school children. Children and their mother/guardians were interviewed or completed questionnaires in the home about fear acquisition and related concerns. A multivariate logistic regression model was evaluated in order to explore the relationship of direct conditioning and modeling variables to fear levels. Both direct conditioning and parent modeling factors were significant independent predictors of fear level even when controlling for gender, age and other sociodemographic and attitudinal factors.

Relationship of pain and symptoms to pubertal development in adolescents

&NA; Temporomandibular disorder (TMD) pain, abdominal pain, migraine and tension‐type headache are more prevalent in women than in men. This study assessed the relationship of back pain, headache, abdominal pain, TMD pain, and the presence of multiple pain conditions to gender and pubertal development in a cross‐sectional, population‐based survey of adolescents. We also examined the association between pubertal development and depressive and somatic symptoms, factors often associated with pain in adults. We hypothesized that prevalence of all pain conditions, as well as rates of other symptoms, would increase as puberty progresses in females, but not males. Subjects (3101 boys and girls, 11–17 years old, selected from an HMO population) reported on the presence of each pain condition in the prior 3 months and completed scales assessing pubertal development, and depressive and somatic symptoms. Data were analyzed using descriptive statistics and multivariate logistic regression. Prevalence rates were weighted for factors affecting response. Prevalence of back pain, headache and TMD pain increased significantly (odds ratios, OR=1.4–2.0, P<0.001) and stomach pain increased marginally with increasing pubertal development in girls. Rates of somatization, depression and probability of experiencing multiple pains also increased with pubertal development in girls (P<0.0001). For boys, prevalence of back (OR=1.9, P<0.0001) and facial pain (OR=1.5, P<0.01) increased, stomach pain decreased somewhat and headache prevalence was virtually unchanged with increasing maturity. For both sexes, pubertal development was a better predictor of pain than was age. Thus it appears that pain, other somatic symptoms and depression increase systematically with pubertal development in girls.

Short- and long-term efficacy of brief cognitive-behavioral therapy for patients with chronic temporomandibular disorder pain: a randomized, controlled trial.

Abstract We evaluated the short‐ and long‐term efficacy of a brief cognitive‐behavioral therapy (CBT) for chronic temporomandibular disorder (TMD) pain in a randomized controlled trial. TMD clinic patients were assigned randomly to four sessions of either CBT (n = 79) or an education/attention control condition (n = 79). Participants completed outcome (pain, activity interference, jaw function, and depression) and process (pain beliefs, catastrophizing, and coping) measures before randomization, and 3 (post‐treatment), 6, and 12 months later. As compared with the control group, the CBT group showed significantly greater improvement across the follow‐ups on each outcome, belief, and catastrophizing measure (intent‐to‐treat analyses). The CBT group also showed a greater increase in use of relaxation techniques to cope with pain, but not in use of other coping strategies assessed. On the primary outcome measure, activity interference, the proportion of patients who reported no interference at 12 months was nearly three times higher in the CBT group (35%) than in the control group (13%) (P = 0.004). In addition, more CBT than control group patients had clinically meaningful improvement in pain intensity (50% versus 29% showed ≥50% decrease, P = 0.01), masticatory jaw function (P < 0.001), and depression (P = 0.016) at 12 months (intent‐to‐treat analyses). The two groups improved equivalently on a measure of TMD knowledge. A brief CBT intervention improves one‐year clinical outcomes of TMD clinic patients and these effects appear to result from specific ingredients of the CBT.

Reliability of clinical temporomandibular disorder diagnoses.

&NA; Temporomandibular disorders (TMD) diagnoses can be viewed as the most useful clinical summary for classifying subtypes of TMD. The Research Diagnostic Criteria for TMD (RDC/TMD) is the most widely used TMD diagnostic system for conducting clinical research. It has been translated into 18 languages and is used by a consortium of 45 RDC/TMD‐based international researchers. While reliability of RDC/TMD signs and symptoms of TMD has been amply reported, the reliability of RDC/TMD diagnoses has not. The aim of the study was to determine the reliability of clinical TMD diagnoses using standardized methods and operational definitions contained in the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Data came from reliability assessment trials conducted at 10 international clinical centers, involving 30 clinical examiners assessing 230 subjects. Intraclass correlation coefficients (ICC) were calculated to characterize the reliability. The reliability of the diagnoses was fair to good. Median ICCs for the diagnoses myofascial pain with and without limited opening were 0.51 and 0.60, respectively. Median ICC for arthralgia was 0.47 and 0.61 for disc displacement with reduction. RDC/TMD diagnoses of disc displacement without reduction, osteoarthritis and osteoarthrosis were not prevalent enough to calculate ICCs, but percent agreement was always >95%. The reliability of diagnostic classification improved when diagnoses were grouped into pain versus non‐pain diagnoses (ICC=0.72) and for detecting any diagnosis versus no diagnosis (ICC=0.78). In clinical decision‐making and research, arriving at a reliable diagnosis is critical in establishing a clinical condition and a rational approach to treatment. The RDC/TMD demonstrates sufficiently high reliability for the most common TMD diagnoses, supporting its use in clinical research and decision making.

Predictors of onset of facial pain and temporomandibular disorders in early adolescence.

Abstract There are few prospective studies assessing risk factors for onset of temporomandibular (TMD) pain disorders in any age group. The aim of this prospective cohort study was to identify risk factors for onset of clinically significant TMD pain (i.e., pain meeting research diagnostic criteria for myofascial pain and/or arthralgia) during early adolescence. Subjects were 1,996 boys and girls, initially 11 years old, randomly selected from a large nonprofit health care system. Subjects completed a baseline telephone interview and were followed up with mailed questionnaires every 3 months for 3 years. At baseline and all follow ups, subjects were asked to report the presence of facial pain in the past 3 months. Subjects reporting a first onset of facial pain received a standardized clinical examination. In multivariate analyses, baseline predictors of clinically significant pain included female gender [Odds Ratio (OR) = 2.0, 95% Confidence Interval (CI) = 1.2–3.3] and negative somatic and psychological symptoms including somatization (OR = 1.8, CI = 1.1–2.8), number of other pain complaints (OR = 3.2, CI = 1.7–6.1) and life dissatisfaction (OR = 4.1, CI = 1.9–9.0). Many of the risk factors for onset of clinically significant TMD pain in adolescents are similar to risk factors for onset of TMD and other pain problems in adults, as well as risk factors for onset of other pain conditions in adolescents. These findings suggest that the development of TMD pain in adolescence may reflect an underlying vulnerability to musculoskeletal pain that is not unique to the orofacial region.

The roles of beliefs, catastrophizing, and coping in the functioning of patients with temporomandibular disorders

&NA; Pain‐related beliefs, catastrophizing, and coping have been shown to be associated with measures of physical and psychosocial functioning among patients with chronic musculoskeletal and rheumatologic pain. However, little is known about the relative importance of these process variables in the functioning of patients with temporomandibular disorders (TMD). To address this gap in the literature, self‐report measures of pain, beliefs, catastrophizing, coping, pain‐related activity interference, jaw activity limitations, and depression, as well as an objective measure of jaw opening impairment, were obtained from 118 patients at a TMD specialty clinic. Controlling for age, gender, and pain intensity, significant associations were found between (1) pain beliefs and activity interference, depression, and non‐masticatory jaw activity limitations, (2) catastrophizing and activity interference, depression, and non‐masticatory jaw activity limitations, and (3) coping and activity interference and depression. Controlling for age, gender, pain intensity, and the other process variables, significant associations were found between (1) beliefs and activity interference and depression, and (2) catastrophizing and depression. No process variable was associated significantly with the objective measure of jaw impairment. The results suggest that for patients with moderate or high levels of TMD pain and dysfunction, beliefs about pain play an important role in physical and psychosocial functioning.

An Explanatory Model of the Dental Care Utilization of Low-Income Children

OBJECTIVES Factors related to the utilization of dental care by 5- to 11-year-old children from low-income households were investigated using a comprehensive multivariate model that assessed the contribution of structure, history, cognition, and expectations. The influence of dentist-patient interactions, psychosocial and health beliefs, particularly fear of the dentist, on utilization were investigated. METHODS Children were chosen randomly from public schools, and 895 mothers were surveyed and their children were interviewed in the home. Utilization was studied during the 1991-1992 school year, including a 6-month follow-up period after the interview. RESULTS The overall utilization rate was 63.2%, and the rate for nonemergent (preventive) visits was 59.9%. Utilization was unrelated to actual oral health status. Race and years the guardian lived in the United States were predictive of an episode of care. Preventive medical visits and perceived need were strong predictors of a visit to the dentist, as were beliefs in the efficacy of dental care. Mothers who were satisfied with their own care and oral health and whose children were covered by insurance were more likely to utilize childrens dental care. In contrast, child dental fear and absences from school for family problems were associated with lower rates of utilization. CONCLUSIONS Mutable factors that govern the use of care in this population were identified. These findings have implications for the design of dental care delivery systems for children and their families.

Pain-related catastrophizing: a daily process study.

&NA; Little is known about the extent to which individuals vary versus remain stable in their pain‐related catastrophizing, or to which catastrophizing is associated with pain and related problems on a daily basis. We used daily electronic interviews to examine the: (1) reliability and validity of a brief daily catastrophizing measure; (2) stability of catastrophizing; (3) patient characteristics associated with catastrophizing; (4) associations between catastrophizing and concurrent and subsequent outcomes (pain, activity interference, jaw use limitations, and negative mood), between and within patients; and (5) associations between pain and subsequent catastrophizing. One hundred patients with chronic temporomandibular disorder pain completed electronic interviews three times a day for 2 weeks [mean (SD) number of interviews=46 (15)]. The catastrophizing scale had high internal consistency (Cronbachs &agr;=0.95) and validity (r=0.65 with the Coping Strategy Questionnaire Catastrophizing scale), and catastrophizing was stable (ICC=0.72) over time. Younger age and greater baseline depression, pain, and disability predicted greater daily catastrophizing. Daily catastrophizing was associated significantly with concurrent outcomes, between‐ and within‐subjects (P<0.0001); however, associations with same‐day subsequent outcomes were greatly attenuated after adjusting for prior outcome levels. Similarly, daily pain was associated significantly with subsequent catastrophizing, but this association was no longer statistically significant after adjusting for prior catastrophizing. The data indicate that catastrophizing is stable over short periods of time in the absence of substantial change in pain, and that within patients, times of greater catastrophizing are associated with worse pain, disability, and mood.