Pain following hysterectomy: epidemiological and clinical aspects

It is well known that different surgical procedures like amputation, thoracotomy, inguinal herniotomy, and mastectomy are associated with a risk of developing chronic postsurgical pain. Hysterectomy is the most frequent gynecological procedure with an annual frequency of 5000 hysterectomies for a benign indication in Denmark, but is has not previously been documented in detail to what extent this procedure leads to chronic pain. The aim of this PhD thesis was therefore to describe the epidemiology, type of pain, risk factors, and predictive factors associated with chronic pain after hysterectomy for a benign indication. The thesis includes four papers, of which one is based on a questionnaire study, two are based on a prospective clinical study, and one is a review of chronic pain after hysterectomy. The questionnaire paper included 1135 women one year after hysterectomy. A postal questionnaire about pain before and after hysterectomy was combined with data from the Danish Hysterectomy Database. Chronic postoperative pain was described by 32%, and the identified risk factors were preoperative pelvic pain, previous cesarean section, other pain problems and pain as an indication for hysterectomy. Spinal anesthesia was associated with a decreased risk of having pain after one year. The type of surgery (i.e. abdominal or vaginal hysterectomy) did not influence chronic pain. The prospective paper included 90 women referred for a hysterectomy on benign indication. The tests were performed before, on day 1, and 4 months after surgery and included questionnaires about pain, coping, and quality of life together with quantitative sensory testing of pain thresholds. Seventeen percent had pain after 4 months, and the risk factors were preoperative pain problems elsewhere and a high intensity of acute postoperative pain. Type of surgery was not a risk factor. Preoperative brush-evoked allodynia, pinprick hyperalgesia, and vaginal pain threshold were associated with a high intensity of acute postoperative pain, and preoperative brush-evoked allodynia was also associated with pelvic pain after 4 months. This PhD thesis shows that chronic postoperative pain is present after hysterectomy in 17-32% of women. The identified main risk factors are described above. The findings indicate that it is not the nerve injury itself, but more likely the underlying individual susceptibility to pain that is important for the development of chronic pain after hysterectomy.

Randomized trial of group cognitive behavioral therapy compared with a pain education control for low-literacy rural people with chronic pain

Chronic pain is a common and costly experience. Cognitive behavioral therapies (CBT) are efficacious for an array of chronic pain conditions. However, the literature is based primarily on urban (white) samples. It is unknown whether CBT works in low-socioeconomic status (SES) minority and nonminority groups. To address this question, we conducted a randomized controlled trial within a low-SES, rural chronic pain population. Specifically, we examined the feasibility, tolerability, acceptability, and efficacy of group CBT compared with a group education intervention (EDU). We hypothesized that although both interventions would elicit short- and long-term improvement across pain-related outcomes, the cognitively-focused CBT protocol would uniquely influence pain catastrophizing. Mixed design analyses of variance were conducted on the sample of eligible participants who did not commence treatment (N=26), the intention-to-treat sample (ITT; N=83), and the completer sample (N=61). Factors associated with treatment completion were examined. Results indicated significantly more drop-outs occurred in CBT. ITT analyses showed that participants in both conditions reported significant improvement across pain-related outcomes, and a nonsignificant trend was found for depressed mood to improve more in CBT than EDU. Results of the completer analyses produced a similar pattern of findings; however, CBT produced greater gains on cognitive and affect variables than EDU. Treatment gains were maintained at 6-month follow-up (N=54). Clinical significance of the findings and the number of treatment responders is reported. Overall, these findings indicate that CBT and EDU are viable treatment options in low-SES minority and nonminority groups. Further research should target disseminating and sustaining psychosocial treatment options within underserved populations.

Predictive relationships between chronic pain and negative emotions: a 4-month daily process study using Therapeutic Interactive Voice Response (TIVR)

This article examines temporal relationships between negative emotions and pain in a cohort of 33 patients with chronic musculoskeletal pain enrolled in a telephone-based relapse prevention program (Therapeutic Interactive Voice Response [TIVR]), after 11 weeks of group cognitive behavioral therapy (CBT). Patients were asked to make daily reports to the TIVR system for 4 months after CBT. Patients' daily reports were analyzed with path analysis to examine temporal relationships between 3 emotion variables (anger, sadness, and stress) and 2 pain variables (pain and pain control). As expected, same-day correlations were significant between emotion variables and both pain and pain control. The lagged associations revealed unidirectional relationships between pain and next-day emotions: increased pain predicted higher reports of sadness the following day (P < .05). Conversely, increased pain control predicted decreased sadness and anger the following day (P < .05). Unlike some previous studies, this study did not reveal that an increase of negative emotions predicted increased next-day pain. We speculate that CBT treatment followed by the relapse prevention program teaches patients how to modulate negative emotions such that they no longer have a negative impact on next-day pain perception. The clinical implications of our findings are discussed.

Pain persists in DAS28 rheumatoid arthritis remission but not in ACR/EULAR remission: a longitudinal observational study

INTRODUCTION

Disease remission has become a feasible goal for most rheumatoid arthritis (RA) patients; however, patient-reported symptoms, such as pain, may persist despite remission. We assessed the prevalence of pain in RA patients in remission according to the Disease Activity Score (DAS28-CRP4) and the American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) remission criteria.

METHODS

Data were analyzed from RA patients in the Brigham Rheumatoid Arthritis Sequential Study with data at baseline and 1 year. DAS28 remission was defined as DAS28-CRP4 <2.6. The ACR/EULAR remission criteria included (a) one or more swollen joints, (b) one or more tender joints, (c) C-reactive protein ≤1 mg/dl, and (d) patient global assessment score ≤1. Pain severity was measured by using the pain score from the Multi-Dimensional Health Assessment Questionnaire (MDHAQ). The associations between baseline clinical predictors and MDHAQ pain at baseline and 1 year were assessed by using multivariable linear regression.

RESULTS

Among the 865 patients with data at baseline and 1 year, 157 (18.2%) met DAS28-CRP4 remission criteria at both time points. Thirty-seven (4.3%) met the ACR/EULAR remission criteria at baseline and 1 year. The prevalence of clinically significant pain (MDHAQ pain ≥4) at baseline ranged from 11.9% among patients meeting DAS28-CRP4 remission criteria to none among patients meeting ACR/EULAR remission criteria. Patient global assessment, MDHAQ function, MDHAQ fatigue, MDHAQ sleep, and arthritis self-efficacy were significantly associated with MDHAQ pain in cross-sectional (P ≤ 0.0005) and longitudinal analyses (P ≤ 0.03). Low swollen-joint counts were associated with high MDHAQ pain in longitudinal analyses (P = 0.02) but not cross-sectional analyses. Other measures of inflammatory disease activity and joint damage were not significantly associated with MDHAQ pain at baseline or at 1 year.

CONCLUSIONS

Clinically significant pain continues among a substantial proportion of patients in DAS28 remission but not among those in ACR/EULAR remission. Among patients in DAS28 remission, patient global assessment, disability, fatigue, sleep problems, and self-efficacy are strongly associated with pain severity at baseline and 1 year, whereas inflammatory disease activity and joint damage are not significantly associated with elevated pain severity at either baseline or 1 year.

Bowel function during pain therapy with oxycodone/naloxone prolonged-release tablets in patients with advanced cancer

BACKGROUND

The World Health Organization (WHO) step-III opioids are often required right from the start of pain therapy in order to achieve sufficient symptom control. Bowel dysfunction, particularly constipation, is one of the most frequent and persistent side effects of opioid therapy, and it is known to cause considerable distress in many patients. The aim of the study was to evaluate whether patients with advanced cancer and moderate to severe cancer pain will benefit from treatment with oxycodone/naloxone prolonged-release tablets (OXN), with particular regard to constipation.

MATERIAL AND METHODS

In this exploratory, non-randomised, open-label, mono-centre study we evaluated the bowel function in palliative care patients treated with OXN. During the treatment phase patients were titrated up to an adequate pain control. The Bristol Stool Form Scale (BSFS) (type 1-7) and Bowel Function Index (BFI) (0-100) were used to assess consistency and frequency of bowel movements. Global patient satisfaction was assessed with Patient Global Impression of Change Scale (PGIC) (1-7).

STATISTICS

mean ± SD, significance p<0.05.

RESULTS

Twenty-six patients [10 male patients (38.5%)] were included; mean age 70.6 ± 14.0 years, length of stay 22.6 ± 21.2 days. At admission all patients had opioid-induced constipation. During the observation period of 14 days the daily mean dose of OX was 36.2 ± 17.2 mg and of N 15.4 ± 5.3 mg. In five cancer patients pain control was not sufficient under the approved maximum total daily dose of 40/20 mg OXN; therefore switching to hydromorphone. BFI improved significantly in 21 patients (72.4 ± 17.0 vs. 36.8 ± 13.4) (p<0.0001); stool consistency (BSFS) improved from type 2.0 ± 0.7 to 4.9 ± 1.0 (p<0.0001). PGIC at discharge was 1.9 ± 0.8.

DISCUSSION

Patients with OXN treatment throughout the whole study phase showed a clinically relevant improvement in pain intensity and bowel function as well as increased satisfaction. Well-known disadvantages of laxative treatment might be spared or even circumvented under OXN treatment, if appropriate.

International guidelines for prevention and management of post-operative chronic pain following inguinal hernia surgery

PURPOSE

To provide uniform terminology and definition of post-herniorrhaphy groin chronic pain. To give guidelines to the scientific community concerning the prevention and the treatment of chronic groin and testicular pain.

METHODS

A group of nine experts in hernia surgery was created in 2007. The group set up six clinical questions and continued to work on the answers, according to evidence-based literature. In 2008, an International Consensus Conference was held in Rome with the working group, with an audience of 200 participants, with a view to reaching a consensus for each question.

RESULTS

A consensus was reached regarding a definition of chronic groin pain. The recommendation was to identify and preserve all three inguinal nerves during open inguinal hernia repair to reduce the risk of chronic groin pain. Likewise, elective resection of a suspected injured nerve was recommended. There was no recommendation for a procedure on the resected nerve ending and no recommendation for using glue during hernia repair. Surgical treatment (including all three nerves) should be suggested for patients who do not respond to no-surgery pain-management treatment; it is advisable to wait at least 1 year from the previous herniorraphy.

CONCLUSION

The consensus reached on some open questions in the field of post-herniorrhaphy chronic pain may help to better analyze and compare studies, avoid sending erroneous messages to the scientific community, and provide some guidelines for the prevention and treatment of post-herniorraphy chronic pain.

Aberrant drug-related behavior observed during clinical studies involving patients taking chronic opioid therapy for persistent pain and fentanyl buccal tablet for breakthrough pain

CONTEXT

Information on aberrant drug-related behaviors in the clinical study setting is limited.

OBJECTIVES

This retrospective analysis was designed to identify the types and frequency of aberrant drug-related behaviors (including misuse and abuse) and associated patient characteristics in opioid-tolerant patients with chronic pain.

METHODS

Data from opioid-tolerant patients participating in clinical studies of fentanyl buccal tablet (FBT) for breakthrough pain (up to 18 months of clinical study case-report forms) were retrospectively reviewed and coded for abuse, overdose, and aberrant behavior. Aberrant behaviors were categorized as those involving FBT (overuse, lost or stolen study drug) and those not involving FBT (patients seeking prescriptions from other sources, not returning for follow-up).

RESULTS

Of the 1,160 patients evaluated, 10 (<1%) patients had an abuse-related event, 18 (<2%) had a positive urine drug screening (nonprescribed drug or illicit substance), and 12 (1%) had an event consistent with opioid overdose; 124 (11%) had aberrant behaviors related to FBT, and 68 (6%) had aberrant behaviors that were not. Aberrant behaviors were more frequent in men (odds ratio [OR]: 1.5; 95% confidence interval [CI]: 1.1, 2.1; P<0.01), in patients 42 years or younger (OR: 2.5; 95% CI: 1.6, 4.0; P<0.01), and in patients 43 years to 49 years (OR: 1.9; 95% CI: 1.2, 3.1; P<0.01).

CONCLUSION

The incidence of drug abuse events and aberrant drug-related behaviors was relatively low, probably because of the implementation of universal precautions and the controlled clinical study setting. Even in this setting, events occurred, highlighting the limits of screening and the need for ongoing monitoring of aberrant behavior.

Position paper: appropriate use of pharmacotherapeutic agents by the orofacial pain dentist

Orofacial Pain Dentistry is concerned with the prevention, evaluation, diagnosis, treatment, and management of persistent and recurrent orofacial pain disorders. The American Dental Association, through the Commission on Dental Accreditation (CODA), now recognizes Orofacial Pain as an area of advanced education in Dentistry. It is mandated by CODA that postgraduate orofacial pain programs be designed to provide advanced knowledge and skills beyond those of the standard curriculum leading to the DDS or DMD degrees. Postgraduate programs in orofacial pain must include specific curricular content to comply with CODA standards. The intent of CODA standards is to assure that training programs develop specific educational goals and objectives that describe the student/resident’s expected knowledge and skills upon successful completion of the program. A standardized core curriculum, required for accreditation of dental orofacial pain training programs, has now been adopted.Among the various topics mandated in the curriculum are pharmacology and, specifically, pharmacotherapeutics. The American Academy of Orofacial Pain (AAOP) recommends, and the American Board of Orofacial Pain (ABOP) requires, that the minimally competent orofacial pain dentist* be knowledgeable in the management of orofacial pain conditions using medications when indicated. Basic knowledge of the appropriate use of pharmacotherapeutics is essential for the orofacial pain dentist and, therefore, constitutes part of the examination specifications of the ABOP. The minimally competent orofacial pain clinician must demonstrate knowledge, diagnostic skills, and treatment expertise in many areas, such as musculoskeletal, neurovascular, and neuropathic pain syndromes; sleep disorders related to orofacial pain; orofacial dystonias; and intraoral, intracranial, extracranial, and systemic disorders that cause orofacial pain or dysfunction. The orofacial pain dentist has the responsibility to diagnose and treat patients in pain that is often chronic, multifactorial, and complex. Failure to understand pain mechanisms can lead to inaccurate diagnoses and ineffective, delayed, or harmful treatment. It is the responsibility of the orofacial pain dentist to accurately diagnose the cause(s) of the pain and decide if treatment should be dentally, medically, or psychologically oriented, or if optimal management requires a combination of all three treatment approaches. Management may consist of a number of interdisciplinary modalities including, eg, physical medicine, behavioral medicine, and pharmacology or, in rare instances, surgical interventions. Among the essential armamentarium is the knowledge and proper use of pharmacologic agents.

Attributes of response in depressed patients switched to treatment with duloxetine

BACKGROUND

This study was designed to assess clinical and functional outcomes associated with switching to duloxetine treatment in patients with major depressive disorder (MDD) experiencing emotional and painful physical symptoms in their current episode.

METHODS

In this 8-week, multinational, multicentre, single-arm, open-label clinical trial, 242 MDD patients were switched to duloxetine 60 mg/day after selective serotonin reuptake inhibitor (SSRI) or serotonin and norepinephrine reuptake inhibitor (SNRI) treatment. The primary analysis compared mean change from baseline in Brief Pain Inventory-Modified Short Form (BPI-SF) interference score between initial responders [≥ 50% reduction from baseline on the 17-item Hamilton Depression Rating Scale (HAMD(17)) Maier subscale] and initial non-responders after 4 weeks. Initial responders continued with duloxetine 60 mg/day. Initial non-responders received duloxetine 120 mg/day for the remaining 4 weeks. Depression, pain, anxiety and functional outcomes were also compared after 8 weeks.

RESULTS

BPI-SF interference decreased from baseline in initial responders (n = 108) and initial non-responders (n = 85) after 4 weeks of duloxetine treatment, with greater reductions in initial responders [BPI-SF mean difference in reduction: 1.01 (95% CI 0.42-1.61); p < 0.001]. Reductions in pain interference favouring initial responders were also apparent after 8 weeks [0.68 (95% CI: 0.03-1.33); p = 0.042]. Depression, pain, anxiety and function improved over 8 weeks across patient groups.

CONCLUSIONS

Elements of core mood and pain are important residual symptoms following poor treatment response in MDD. Early improvement in these symptoms after switching to duloxetine indicated an increased chance of functional recovery.