References: Chronic Pain 1997; Volume 3 Issue 9

1. AUTHOR	Andary-M-T, Crewe-N, Ganzel-S-K, Haines-Pepi-C, Kulkarni-M-R, Stanton-D-F, Thompson-A, Yosef-M.
INSTITUTION	College of Osteopathic Medicine, Michigan State University, East Lansing 48823, USA.
TITLE	Traumatic brain injury/chronic pain syndrome: a case comparison study.
SOURCE	Clin-J-Pain 1997 Sep, VOL: 13 (3), P: 244-50, ISSN: 0749-8047.
ABSTRACT	OBJECTIVE: To identify the pretreatment characteristics and progress in treatment and outcomes of chronic pain patients, with and without concomitant traumatic brain injury (TBI). DESIGN AND PATIENTS: Retrospective cohort study of 12 consecutive patients in a chronic pain treatment program who were discovered to have previously untreated brain injury and a cohort of 12 chronic pain patients from the same program matched for age and sex who did not have brain injury. SETTING: Interdisciplinary university-based outpatient rehabilitation medicine clinic. MAIN OUTCOME MEASURES: Length of time in treatment and vocational outcomes. RESULTS: A surprising number of patients referred for treatment of chronic pain were found to have history and symptoms indicative of previously untreated or undiagnosed mild traumatic brain injury (n = 21 of 65). Of these, 12 received therapy for both their brain injury and chronic pain. The 12 treated, dual diagnosed patients did not differ in terms of education, employment status, or marital status from the chronic pain patients. Those with TBI were more likely to have sustained an automobile injury and less likely to have a work-related injury. On admission, 25% of each group were working, and at discharge, that proportion reached 75% for each group. Those with TBI required significantly longer treatment (459 consecutive days) from intake to discharge compared with the control group (295 days). CONCLUSION: Patients who exhibit memory or concentration problems, who express confusion about their diagnosis, who were injured in an automobile accident, or who complain of pain in the head, neck, or arms should be questioned about the possibility of concurrent TBI. Most of these patients can achieve successful employment outcomes, however, the TBI group may require a longer treatment time. Author.

2. AUTHOR	Iverson-G-L, McCracken-L-M.
INSTITUTION	Department of Psychiatry, University of British Columbia, Vancouver, Canada.
TITLE	'Postconcussive' symptoms in persons with chronic pain.
SOURCE	Brain-Inj 1997 Nov, VOL: 11 (11), P: 783-90, ISSN: 0269-9052.
ABSTRACT	The purpose of this study was to examine the base rate of cognitive and neurobehavioural complaints in patients with chronic pain (N = 170) who had not sustained a head injury. The patients completed a packet of questionnaires that contained numerous questions regarding physical, cognitive, and psychological symptoms. The 'postconcussive- like' symptoms were selected and analysed. Specific symptom endorsement rates ranged from 5% to 76.5%. Disturbed sleep, fatigue, and irritability were reported by the majority of chronic pain patients. Cognitive complaints relating to forgetfulness (29%), difficulty maintaining attention (18%), and difficulty with concentration or thinking (16.5%) were endorsed by a significant minority of patients. Most patients (80.6%) endorsed three or more symptoms from Category C of the DSM-IV Postconcussional Disorder research criteria. This study further illustrates that postconcussive-like symptoms are not unique sequelae of mild head injury, and the presence of chronic pain should be considered when interpreting patients' physical, cognitive, and psychological complaints following closed head injury. Author.

3. AUTHOR	Tait-R-C, Chibnall-J-T.
INSTITUTION	Department of Psychiatry and Human Behavior, Saint Louis University School of Medicine, MO 63104, USA.
TITLE	Physician judgments of chronic pain patients.
SOURCE	Soc-Sci-Med 1997 Oct, VOL: 45 (8), P: 1199-205, ISSN: 0277-9536.
ABSTRACT	Recent evidence has indicated that physician judgments of patients can be influenced by contextual factors. This study examined three contextual factors relevant to hypothetical patients with low back pain, using vignettes that were varied in a 2 x 2 x 2 factorial design: level of reported pain (high vs low), level of supporting medical evidence (high vs low), and the valence of the physician- patient interaction (positive vs negative). Perceived levels of pain, disability, emotional distress, and somatic preoccupation were rated by internists after reading a vignette. Ratings of pain and disability were lower for patients without supporting medical evidence; ratings of distress, somatic preoccupation, and disability were greater for patients who exhibited negative rather than positive affect; internist ratings of pain were lower than patient ratings among patients reporting high levels of pain, while ratings were inflated for patients with low levels of pain. The results suggest that characteristics of both the patient and the situation may influence medical judgments. Author.

4. AUTHOR	Chibnall-J-T, Tait-R-C, Ross-L-R.
INSTITUTION	Department of Psychiatry, Saint Louis University, School of Medicine, Missouri 63104, USA.
TITLE	The effects of medical evidence and pain intensity on medical student judgments of chronic pain patients.
SOURCE	J-Behav-Med 1997 Jun, VOL: 20 (3), P: 257-71, ISSN: 0160-7715.
ABSTRACT	This study examined symptom judgments made by medical students of hypothetical chronic low back pain patients. Eight vignettes were varied as to the pain intensity reported by the hypothetical patient (low vs. moderate vs. high vs. very high) and the availability of medical evidence supportive of the pain report (present vs. absent). Ninety-five subjects read vignettes and made judgments of patient emotional distress, pain intensity, and pain-related disability. Subjects significantly discounted pain level when intensity was high but slightly augmented pain level when intensity was low. Judgments of pain and disability were higher for patients for whom medical evidence was present compared to those for whom it was absent. The results support and extend previous research on the effects of situational and patient variables on observer pain judgments. Future research should examine the influence of these biasing variables on the assessment and treatment of chronic pain patients. Author.

5. AUTHOR	Lumley-M-A, Asselin-L-A, Norman-S.
INSTITUTION	Department of Psychology, Wayne State University, Detroit, MI 48202, USA.
TITLE	Alexithymia in chronic pain patients.
SOURCE	Compr-Psychiatry 1997 May-Jun, VOL: 38 (3), P: 160-5, ISSN: 0010-440X.
ABSTRACT	Prior studies of alexithymia in chronic pain patients have used unvalidated alexithymia measures or have not controlled for treatment-seeking status. In this study, we compared 30 patients with chronic pain and patients seeking treatment for two other problems: nicotine dependence (n = 32) or moderate obesity (n = 25). Alexithymia was assessed with the well-validated Toronto Alexithymia Scale (TAS) and also with the Alexithymia Provoked Response Questionnaire (APRQ). On both alexithymia measures, chronic pain patients were more alexithymic than nicotine-dependent and obese patients; the latter two groups did not differ. Chronic pain patients had greater psychopathology on the Minnesota Multiphasic Personality Inventory-2 (MMPI-2), and both alexithymia measures correlated positively with certain types of psychopathology. We conclude that alexithymia is increased among patients with chronic pain, that this relationship is not confounded by a treatment-seeking bias, and that alexithymia may contribute to both chronic pain and psychopathology. Author.

6. AUTHOR	Fishbain-D-A, Cutler-R, Rosomoff-H-L, Rosomoff-R-S.
INSTITUTION	Department of Psychiatry, University of Miami, School of Medicine, Florida 33131, USA.
TITLE	Chronic pain-associated depression: antecedent or consequence of chronic pain? A review.
SOURCE	Clin-J-Pain 1997 Jun, VOL: 13 (2), P: 116-37, ISSN: 0749-8047 129 Refs.
ABSTRACT	OBJECTIVE: To determine the current status for the association of chronic pain and depression and to review the evidence for whether depression is an antecedent or consequence of chronic pain (CP). DESIGN: A computer and manual literature review yielded 191 studies that related to the pain-depression association. These reports were reviewed and sorted into seven categories relating to the topic of this paper. Eighty-three studies were then selected according to inclusion criteria and subjected to a structured review. SETTING: Any medical treatment setting including pain treatment as inclusion criteria for selection of studies. PATIENTS: Any patients with any type of chronic pain. RESULTS: The reviewed studies were consistent in indicating that there is a statistical relationship between chronic pain and depression. For the relationship between pain and depression, there was greater support for the consequence and scar hypotheses than the antecedent hypothesis. CONCLUSIONS: Depression is more common in chronic pain patients (CPPs) than in healthy controls as a consequence of the presence of CP. At pain onset, predisposition to depression (the scar hypothesis) may increase the likelihood for the development of depression in some CPPS. Because of difficulties in measuring depression in the presence of CP, the reviewed studies should be interpreted with caution. Author.

7. AUTHOR	Chabal-C, Erjavec-M-K, Jacobson-L, Mariano-A, Chaney-E.
INSTITUTION	Anesthesiology Department, University of Washington, Seattle, USA.
TITLE	Prescription opiate abuse in chronic pain patients: clinical criteria, incidence, and predictors.
SOURCE	Clin-J-Pain 1997 Jun, VOL: 13 (2), P: 150-5, ISSN: 0749-8047.
ABSTRACT	OBJECTIVES: Opiates are commonly used to treat patients with chronic nonmalignant pain. There is much controversy over the definition, incidence, and risk factors of prescription opiate abuse in chronic pain treatment. The present study, done at the Seattle VA Medical Center, was designed to create opiate abuse criteria, test inter- rater reliability of the criteria, apply the criteria to a group of chronic pain patients, and correlate the risk of opiate abuse with the results of alcohol and drug testing. DESIGN/OUTCOME MEASURES: A committee of experienced pain providers designed a five-point prescription opiate abuse checklist based on DSM-III-R parameters. The criteria were then applied to patients enrolled in the pain clinic. The reliability of the criteria were determined using two providers who were familiar with every patient in the clinic. Drug, alcohol, and psychosocial testing were correlated with the risk of opiate abuse. RESULTS: A total of 19% (76/403) of all pain clinic patients were using chronic opiates. Thirty-four percent (26/76) met one, and 27.6% (21/76) met three or more of the abuse criteria. The criteria had an inter-rater reliability of > 0.9. There were no differences between chronic opiate users (n = 76) and opiate abusers (n = 21) for a history of drug or alcohol abuse or on psychosocial testing. CONCLUSIONS: Prescription opiate abuse criteria for use in patients with chronic nonmalignant pain were designed. The criteria had good reliability and can be applied during normal clinic interactions. The percentage of chronic opiate users who become opiate abusers in pain treatment is within the range reported by others. Past opiate or alcohol abuse or psychosocial testing on clinic admission failed to predict who would become an opiate abuser. The criteria can be used to identify patients who will subsequently require more intensive treatment or intervention or can be used as an outcome to measure to test the effectiveness of treatment strategies. Author.

8. AUTHOR	Kouyanou-K, Pither-C-E, Wessely-S.
INSTITUTION	Institute of Psychiatry, St. Thomas' Hospital, London, UK.
TITLE	Medication misuse, abuse and dependence in chronic pain patients.
SOURCE	J-Psychosom-Res 1997 Nov, VOL: 43 (5), P: 497-504, ISSN: 0022-3999.
ABSTRACT	We report the prevalence of drug use, misuse, abuse, and dependence in 125 chronic pain patients attending specialist pain clinics in South London. A total of 110 patients (88%) were taking medications for their pain problem. Opioid analgesics (69.6%), nonopioids (48%), antidepressants (25%), and benzodiazepines (17.6%) were the drugs most frequently used. Psychoactive substance abuse or dependence (DSM-III-R) was diagnosed in 12%. A total of 9.6% of the patients met the DSM-III-R criteria for substance abuse or dependence in remission. Data are also presented on the misuse and abuse of nonpsychoactive drugs, qualitative information on how patients use drugs, and the information they have received about medication. Author.

9. AUTHOR	Brenne-E, van-der-Hagen-K, Maehlum-E, Husebo-S.
INSTITUTION	Anestesi og intensivavdelingen, Haukeland Sykehus, Bergen.
TITLE	(Treatment chronic pain with amitriptyline. A double-blind dosage study with determination of serum levels). TT Behandling av pasienter med kroniske smerter med amitriptylin. Dobbeltblind doseringsundersokelse med serumkonsentrasjonsbestemmelse.
SOURCE	Tidsskr-Nor-Laegeforen 1997 Oct 10, VOL: 117 (24), P: 3491-4, ISSN: 0029-2001.
ABSTRACT	The aim of this study was to find an optimal analgesic dose of amitriptyline, and at the same time examine whether a therapeutic window existed for this analgesic effect. 85 patients with chronic, non-malignant pain were included in a double-blind treatment regime with four doses of amitriptyline (10, 25, 50 or 100 mg). A blood sample was taken at steady state. The results showed 25 mg amitriptyline to have a good analgesic and sleep regulatory effect. The four different doses of amitriptyline did not show any significant difference in efficacy. No therapeutic window was found, but one cannot exclude that it exists. Low-dose amitriptyline, as a non-addictive drug, is a good alternative in the treatment of chronic pain, independent of co-morbid depression. Author.

10. AUTHOR	Jung-A-C, Staiger-T, Sullivan-M.
INSTITUTION	Department of Medicine, University of Washington, Seattle 98195, USA.
TITLE	The efficacy of selective serotonin reuptake inhibitors for the management of chronic pain (see comments).
SOURCE	J-Gen-Intern-Med 1997 Jun, VOL: 12 (6), P: 384-9, ISSN: 0884-8734.
CM	Comment in: ACP-J-Club 1998 Jan-Feb; 128(1):3.
ABSTRACT	OBJECTIVE: To assess the effectiveness of selective serotonin reuptake inhibitors (SSRIs) in the management of chronic pain. METHODS: Randomized, controlled trials of SSRIs in the management of chronic pain were identified by searching MEDLINE from 1966 to 1997 and by contacting the manufacturers of SSRIs available in the United States. MAIN RESULTS: Nineteen studies were identified, including 10 on the treatment of headache, 3 on diabetic neuropathy, 3 on fibromyalgia, and 3 on mixed-chronic pain. SSRIs were consistently helpful for mixed-chronic pain. Results were conflicting for migraine headache, tension headache, diabetic neuropathy, and fibromyalgia. CONCLUSIONS: SSRIs appear to be beneficial for mixed-chronic pain. It is unclear, from the available evidence, whether SSRIs are beneficial for migraine headaches, tension headaches, diabetic neuropathy, or fibromyalgia. For those patients it may be reasonable to reserve SSRIs for those who fall to respond to other medications or who are intolerant of their side effects. Author.

11. AUTHOR	Lang-P.
TITLE	The treatment of chronic pain by epidural spinal cord stimulation--a 15 year follow up; present status.
SOURCE	Axone 1997 Jun, VOL: 18 (4), P: 71-3, ISSN: 0834-7824.
ABSTRACT	Pain is necessary for survival but chronic pain is disabling and causes significant health and economic problems. This study provides an understanding of the future for spinal cord stimulation. Stimulation by means of chronically implanted electrodes, was carried out in 200 patients with pain of varied benign organic etiology. In 177 of them, pain was confined to the failed back syndrome. Most patients were referred by a Pain Management Service. 226 epidural implants were used: 80 unipolar, 59 Resume, 12 bipolar, and 75 quadripolar. Patients were followed for periods of 6 months to 12 years, with a mean follow-up of 44 months. 84 patients (42%) were able to control their pain by stimulation alone, 22 patients (11%) needed occasional analgesic supplements along with their stimulation program. Pain secondary to failed back syndrome, multiple sclerosis, peripheral vascular disease, sympathetic dystrophy and diabetic neuropathy responded favorably. Pain due to cauda equina injury, paraplegic pain and phantom limb pain responded poorly. Complications included wound infection, displaced or fracture electrode, and fibrosis at the stimulating tip. Spinal cord stimulation has proven to be effective in the treatment of chronic benign pain. Author.

12. AUTHOR	Holsheimer-J.
INSTITUTION	Department of Electrical Engineering, University of Twente, Enschede, The Netherlands.
TITLE	Effectiveness of spinal cord stimulation in the management of chronic pain: analysis of technical drawbacks and solutions.
SOURCE	Neurosurgery 1997 May, VOL: 40 (5), P: 990-6; discussions 996-9, ISSN: 0148-396X.
ABSTRACT	OBJECTIVE: A major drawback of currently available spinal cord stimulation (SCS) systems for the management of chronic intractable pain, especially of widespread pain patterns as in reflex sympathetic dystrophy, is the generally limited paresthesia coverage. The aim of this study is to analyze the origin of this problem and to provide solutions. METHODS: Results from theoretical studies, in which a computer model was used to mimic the effects of SCS on spinal nerve fibers, were used to analyze which factors may limit paresthesia coverage. Model predictions were verified by empirical data from clinical literature. RESULTS: When using common SCS electrodes, both perception threshold and motor/discomfort threshold are generally related to dorsal root stimulation. Because these thresholds have a small ratio (approximately 1:1.4), stimulation of dorsal column fibers and paresthesia coverage is limited by this small range of stimulation. When the distance between the epidural electrode and spinal cord is large (midthoracically), the threshold for dorsal column stimulation exceeds discomfort threshold, resulting only in segmental paresthesia. The range of dorsal column stimulation and paresthesia coverage can be improved when using either an optimally dimensioned rostrocaudal bi-/tripole or a transverse tripole ("guarded cathode"). When applying the latter in combination with a dual channel pulse generator providing simultaneous pulses, paresthesias can simply be changed to optimally cover the painful area. CONCLUSION: Paresthesia coverage and pain management by SCS can be improved when using electrodes as proposed. Author.