Chronic pain and posttraumatic stress disorder: mutual maintenance?

Common sequelae following a traumatic event include chronic pain and posttraumatic stress disorder (PTSD). Over the last decade, the literature relating to PTSD has become progressively more sophisticated, resulting in well-supported theories and treatments for sufferers. Equivalent research relating to chronic pain has more recently gathered momentum. However, to date there has been minimal attention devoted to the concurrence of the two disorders, even though high comorbidity has been noted. This review begins by briefly summarizing the literature relating to the two disorders in terms of symptoms, prevalence and comorbidity. It explicates the major psychological theories of chronic pain and PTSD and reviews the evidence relating what factors maintain the disorders. A number of pathways by which chronic pain and PTSD may be mutually maintaining are highlighted. We conclude that chronic pain and PTSD are mutually maintaining conditions and that there are several pathways by which both disorders may be involved in the escalation of symptoms and distress following trauma. Treatment implications are considered, as are issues for future research.

Chronic pain: a reformulation of the cognitive-behavioural model.

The last few decades has seen psychological theories of chronic pain dominated by behavioural concepts and particularly, by the operant model as described by Fordyce et al. (1968: Fordyce, W., Fowler, R., & DeLateur, B. (1968) An application of behavior modification technique to a problem of chronic pain. Behaviour Research and Therapy, 6, 105-107, 1976: Fordyce, W.E. (1976) Behavioral methods for chronic pain and illness. St Louis, MO: C. V Moseby). More recently, cognitive constructs have been included, giving the impression that the operant theory of chronic pain has been replaced by a cognitive-behavioural theory (CBT). Given the fact that CBTs were introduced essentially to overcome some inherent problems with operant theory, it is notable that they are still very much based on operant theory and continue to be founded upon operant principles. Further, the extent to which CBTs (at this stage) have included contemporary cognitive research has been limited. This paper argues that it is of questionable validity to continue to include problematic concepts (e.g., operant principles) into a revised theory (e.g., CBT). Instead, consistent with research from other areas (particularly the anxiety disorders), chronic pain and the problems associated with it may be better explained by a reformulated cognitive-behavioural theory which although not ignoring the observable behaviours of pain patients and their associations with social reinforcers, interprets these phenomena from a cognitive perspective. Thus, a modified CBT is proffered, focusing more directly on patients' thoughts about, and appraisals of, their pain. Evidence in support of such a theory is provided, as are suggestions for further research and the implications such a theory has for treatment.

Assessing the significant others of chronic pain patients: the psychometric properties of significant other questionnaires.

Contemporary reviews of psychological models of chronic pain have favoured behavioural and cognitive-behavioural formulations. These have often assumed that pain behaviours are maintained by environmental reinforcers. One of the most commonly hypothesized sources of reinforcement has been patients' significant others. Further, it has often been recognized that significant others may also be affected by pain behaviours and that they may experience changes in their lifesyles and in their mood as a consequence of living with someone who has pain. Somewhat surprisingly, relatively little clinical research has been published investigating significant others and their relationships with pain patients. Among other things, one of the limiting factors has been the lack of measurement tools available for assessing the relevant variables thought to be important with regards to significant others (such as their responses to, and perceptions of, chronic pain). This study attempted to remedy this situation by developing and testing the psychometric properties of a number of questionnaires specifically designed for significant others of chronic pain patients. The questionnaires have been selected to assess both significant others' (behavioural and cognitive) responses to pain as well as the extent to which pain impacts on their lives. Although not all of the questionnaires were found to possess equally strong psychometric properties, the availability of several solid measures opens the way for more empirical analyses of significant others and their interactions with chronic pain patients.

Immediate postgadolinium spoiled gradient-echo MRI for evaluating the abdominal aorta in the setting of abdominal MR examination.

To assess the reproducibility and image quality of immediate postgadolinium chelate spoiled gradient-echo MRI in demonstrating disease of the abdominal aorta. All patients (27 patients: 21 men, 6 women) with substantial disease of the abdominal aorta, who underwent abdominal MR examinations at 1.5 T between 1991 and 1995, were entered in the study. Patients were referred for evaluation of suspected aortic disease (14 patients) or other abdominal diseases (13 patients). Three experienced investigators manually measured luminal and external aortic wall diameters and rated image quality, definition of inner and outer walls, extent of disease, and presence of other abdominal abnormalities, in an independent fashion. A cardiovascular surgeon then rated all studies to determine whether clinical management could be based on the MR findings alone. There was 98 to 99% agreement in measurements of luminal and external wall diameter between the three investigators. Overall image quality was rated as good in 77.8 to 88.9% of patients. A total of 31 additional nonaortic abdominal abnormalities were detected by all observers. The cardiovascular surgeon rated 25 of 27 studies as adequate to determine clinical management based on MR findings alone. Immediate postgadolinium spoiled gradient-echo MRI is a reproducible technique for the demonstration of abdominal aortic disease and possesses good image quality. Advantages of this technique include simultaneous evaluation of other nonvascular diseases of the abdomen, short examination time, and easy implementation as part of routine abdominal MRI scanning protocol.

Comparison of manual and automated probing in an untreated periodontitis population.

Diagnosis of periodontal disease progression involves recording two probing attachment level measurements over an adequate time interval. A diagnostic instrument which exhibits less measurement variability allows for increased sensitivity and earlier disease detection. Traditionally, a manual probe with an occlusal stent of the cementoenamel junction (CEJ) as a reference landmark has been the method of choice. Automated probes that use an occlusal disk as the reference landmark have been developed as an alternative means of measure. The aim of this study was to compare the variability of these two probing methods. Four hundred eleven (411) interproximal sites in 46 untreated periodontitis patients were monitored by a single examiner over a 6-month period. Each site was measured on a monthly basis, first with an automated probe (AP) followed by a manual probe (MP) in combination with a custom-fabricated acrylic stent. Measurement variability of the two probing methods was also compared over a 7-day interval. The AP measurements were significantly more variable than the MP measurements (P < 0.001) when considering the variability between two passes at the same visit. Over the 6-month period, the MP measurements demonstrated significantly more variability than the AP measurements (P < 0.001). It was also noted that MP measurements exhibited more variability at sites with frequent bleeding during the 6 months of the study (P = 0.006). The results of this study demonstrate that AP may have less variability of attachment level measurements over a 6-month period and may be less influenced by local inflammatory changes. However, future comparison studies should include multiple examiners to reduce examiner bias and should alternate the probing method to reduce bias created by local tissue changes from multiple probings.

Identifying adverse events caused by medical care: degree of physician agreement in a retrospective chart review.

OBJECTIVE: To 1) assess the degree of agreement among physicians on the cause of previously flagged adverse outcomes and 2) relate the findings to systems of quality assurance and performance assessment and proposals for no-fault compensation for medical injuries. DESIGN: Observational study of 7533 pairs of "structured implicit" reviews (subjective opinions based on guidelines) of medical records done by 127 physicians working independently. SETTING: Random sample of 51 inpatient facilities in New York State. PATIENTS: Random sample of inpatient medical records from the selected facilities. MEASUREMENTS: 1) Number of agreed-upon adverse events compared with the number of cases of extreme disagreement and 2) internally and indirectly standardized rates at which physician reviewers found adverse events (injuries to patients caused at least in part by medical management). RESULTS: In 12.9% of cases (971 of 7533), the two physicians in a pair had extreme disagreement about the occurrence of an adverse event. These cases outnumbered those in which both reviewers found an adverse event (10%; n = 757). Agreement was highest for wound infections and lowest for adverse events attributed to failure to diagnose or lack of therapy. The amount of experience the physicians had in reviewing records tended to increase the level of agreement. Even after standardization to the results of the entire sample, individual physicians' rates of finding at least slight evidence of an adverse event varied widely (range, 9.9% to 43.7%) (P < 0.001). CONCLUSIONS: Structured implicit reviews produced disagreement on the causes of adverse patient outcomes. If systems of quality assurance, performance audits, or no-fault patient compensation are to succeed, methods for overcoming the common tendency toward disagreement among experts must be developed.

Pancreatic masses with inconclusive findings on spiral CT: is there a role for MRI?

This prospective study evaluates the ability of MRI using T1-weighted fat-suppressed spin-echo (T1FS) and dynamic gadolinium chelate (Gd) enhanced spoiled-gradient echo (SGE) to detect the presence of pancreatic tumor in patients in whom spiral CT findings are inconclusive. Sixteen consecutive patients who underwent spiral CT and had findings that were considered inconclusive for pancreatic tumor underwent MR within 2 weeks of CT. Spiral CT and MR images were interpreted in prospective fashion by separate individual investigators blinded to the results of the other imaging modality. CT was performed on a spiral CT scanner. MRI was performed on on a 1.5-T MR machine. Imaging sequences included T1FS pre-Gd and post-Gd and SGE pre-Gd and immediately post-Gd. Data were analyzed using receiver operating characteristic (ROC) analysis. Confirmation was obtained by pancreatic biopsy (n = 4), surgical resection (n = 1), and clinical imaging (n = 4) or clinical follow-up (n = 7). MRI was superior to spiral CT (P = .027) in this selected patient group at detecting or excluding pancreatic tumor by ROC analysis, with areas under the curve of .982 and .764, respectively, which was significant (P = .041). The greatest advantage of MRI was in patients in whom spiral CT demonstrated enlargement of the pancreatic head without clear definition of tumor, which was significant (P = .033). In 10 patients with this CT appearance, MRI demonstrated a high confidence for presence of tumor in four and a high confidence of absence in six. Association of imaging findings with patient diagnosis was significant for MRI (P = .001) but not significant for CT (P = .148). The results of our study suggest that MRI may add significant diagnostic information in patients in whom spiral CT is inconclusive for the presence of pancreatic tumor. The greatest advantage of MRI was in the evaluation of patients in whom spiral CT findings revealed an indeterminate enlarged pancreatic head.

MR findings in diffuse renal parenchymal disease.

This study evaluates the MR appearance of the kidney in diffuse renal parenchymal diseases, using precontrast, and immediate and delayed postgadolinium chelate (Gd), spoiled gradient echo (SGE), and pre- and post-Gd, T1-weighted, fat-suppressed spin-echo MR images to determine if characteristic findings exist for various types of renal disease. One hundred twenty-one patients with renal disease underwent MRI. Underlying diagnoses included: (a) glomerular disease (GD), (b) tubulointerstitial disease (TID), (c) microvascular disease (MVD), (d) ischemic nephropathy (INP), (e) obstructive nephropathy (ON), (f) infectious renal disease (IRD), (g) sickle cell disease (SCD), (h) renal cortical necrosis (CN), and (i) renal insufficiency of unknown etiology (UE). MR examinations of 22 patients with normal kidneys (NK) were evaluated as a control group. The presence of corticomedullary differentiation (CMD) demonstrated strong inverse correlation with serum creatinine concentration (SCr) (r = -.568, P < .001). Mean thickness of the renal cortex was 8.4 and 7.8 mm in patients with NK and Gd, respectively. The mean cortical thickness in patients with MVD, TID/Chemo, INP, and ON was 5.2, 5.6, 5.5, and 4.3 mm, respectively, significantly thinner than the renal cortex in the NK and GD groups (P < .01). Irregularity of the renal cortex was more frequent in MVD (60.9%), IRD (62.5%), ON (55.6%), and TID/other (53.8%) than in GD (3.8%) and NK (0%) (P < .01). Diffuse high SI of the entire medulla on delayed postcontrast images was observed in 25 (20.7%) of the patients with renal disease and none of the NK group. Although no pathognomonic features were found, certain findings were observed that may correlate with the etiology of the kidney disease and, therefore, assist in the differential diagnosis of renal parenchymal disease.

Validation of a screening survey to assess local public health performance.

The study seeks to validate an abbreviated protocol for measuring local public health performance. Primary data were collected during 1993 on a series of indicators keyed to defined public health core functions and their associated practices. The data were obtained from responses provided by local health department directors and were reviewed for accuracy by respective state health department personnel. All local public health jurisdictions (370) in six states were surveyed with a screening protocol. A sample of 36 of these jurisdictions was then resurveyed by means of a full-length protocol using 84 different indicators of public health performance. Correlations between scores obtained from the screening survey and those from the reference survey were high for overall public health performance, for each of the three functions, and for some of the ten practices. A group of only four queries was shown to predict reliably the overall scores. Findings support the conclusion that public health practice can be defined, measured, and monitored. A proposed surveillance system is feasible.

Comparing hospital mortality in adult patients with pneumonia. A case study of statistical methods in a managed care program.

OBJECTIVE: To compare and contrast a managed care program's analysis of differences in hospital mortality with results obtained by accepted statistical methods. DESIGN: A re-analysis of computerized discharge data using the same method used by a managed care program, and using conventional methods of categorical data analysis. One thousand computer simulations of a method for comparing hospitals by severity-adjusted mortality were done to determine the probability of falsely identifying hospitals as high-mortality outliers. SETTING: 22 acute care hospitals in central Pennsylvania. PATIENTS: All adult patients with pneumonia (n = 4587; diagnosis-related groups 089-090) less than 65 years of age who were discharged from the 22 hospitals in 1989, 1990, and 1991, excluding patients with the acquired immunodeficiency syndrome and transplant recipients. MEASUREMENTS: In-hospital mortality adjusted for age and severity of illness using MedisGroups admission severity group score. RESULTS: The hospital that had the highest mortality for adult pneumonia according to the managed care program's analysis did not, according to an appropriate analysis, differ significantly from other area hospitals (likelihood ratio test, P = 0.23). Random variation in this sample of patients with a low average mortality rate (3.5%) showed a 60% chance that 1 or more of the 22 hospitals would be falsely identified as a "high-mortality outlier" when simplistic statistical methods were used. CONCLUSION: Organizations seeking to compare the quality of hospitals and physicians through outcome data need to recognize that simplistic methods applicable to large samples fail when applied to the outcomes of typical patients, such as those admitted for pneumonia. Although these comparisons are much in demand, careful attention must be paid to their statistical methods to ensure validity and fairness.

Longitudinal evaluation of elastase as a marker for the progression of periodontitis.

To determine whether elastase levels in gingival crevicular fluid (GCF) could serve as a marker for the progression of periodontitis, we monitored GCF elastase and periodontal status in selected sites in 32 periodontally healthy volunteers and 31 periodontitis patients at intervals over a 6-month period. Clinical measurements included plaque index, gingival index, bleeding on probing, suppuration, probing depth, clinical attachment level, and relative attachment level measured with an automated disk probe. GCF elastase, detected by reaction with a fluorescent substrate, was assessed visually against fluorescence standards and quantitatively with a fluorometer. Bone loss was detected by subtraction radiography of standardized vertical bite-wing radiographs at baseline and 6 months. Mean visual elastase scores (VES) and quantitative elastase measurements were significantly higher (P < 0.001) in sites from periodontitis patients than in sites from healthy volunteers. When bone loss was used as the criterion for disease progression, significantly higher (P < 0.001) visual and quantitative GCF elastase levels were found at progressing sites than in nonprogressing sites in the periodontitis patients. The odds ratios (OR) for the event of developing bone loss with positive 4-minute and 8-minute VES tests were 4.2 (P < 0.001) and 7.4 (P < 0.001), respectively. When corrected for the tendency of progressing sites to be clustered within a subpopulation of patients, the OR for developing bone loss with the 4-minute and 8-minute VES tests were 3.1 (P < 0.007) and 4.9 (P < 0.001), respectively. These data indicate that sites with high levels of elastase are at significantly greater risk for progressive bone loss as assessed by digital subtraction radiography.