Expectations of treatment outcome in complex cases of patients with chronic pain: A study on the DATAPAIN cohort.

BACKGROUND: A better insight in how the biopsychosocial factors influence patient outcome(s) may provide information that helps selecting the optimal pain management for a specific group. METHODS: Categorization was made in the prospective DATAPAIN registry, in which patients with pain severity (Numeric Rating Scale [NRS]: 7-10), depression or anxiety (Hospital Anxiety and Depression Scale: > 10), and pain catastrophizing (Pain Catastrophizing Scale: > 31) were identified as complex cases. Patient outcomes; treatment satisfaction on the Patient Global Impression of Change (PGIC), pain relief (NRS), pain interference on the Brief Pain Inventory (BPI) and quality of life indicator General Perceived Health (GPH) were evaluated. Logistic regression analyzed if belonging to the complex cases showed modification in the outcome of the PGIC and GPH. Linear regression was observed if complex cases differed in average reduction in pain relief and interference compared to non-complex cases. RESULTS: 1637 patients were included, of which 345 (21.08%) were considered complex cases. The changes in scores of pain relief and BPI active subscale were not significantly different between groups. The BPI affective subscale had a different change in score (-0.509; p: 0.002). The complex cases had an odds ratio (OR) of 0.59 (95% confidence interval [CI]: 0.36-0.77) on treatment satisfaction compared to non-complex cases, and an OR of 0.28 (95% CI: 0.11-0.56) on the GPH. CONCLUSION: When treating patients with complex cases, desired treatment outcome(s) should be recognized by specialists and patients, as these may be less likely to occur.

Long-Term Evaluation of Spinal Cord Stimulation in Patients With Painful Diabetic Polyneuropathy: An Eight-to-Ten-Year Prospective Cohort Study.

OBJECTIVE: This study aimed to evaluate the long-term effects of spinal cord stimulation (SCS) in patients with painful diabetic polyneuropathy (PDPN). MATERIALS AND METHODS: This prospective cohort study was the eight-to-ten-year follow-up of a previously performed pilot and randomized controlled trial on the effects of SCS in PDPN, initiated by the multidisciplinary pain center of Maastricht University Medical Center+. The study population consisted of a subgroup of patients who still used SCS treatment ≥ eight years after implantation (n = 19). Pain intensity scores (numeric rating scale [NRS]) during the day and night and data on secondary outcomes (ie, quality of life, depression, sleep quality) were reported during yearly follow-up consultations. Long-term efficacy of SCS was analyzed by comparing the most recently obtained data eight to ten years after implantation with those obtained at baseline. RESULTS: Pain intensity, day and night, was significantly (p < 0.01) reduced by 2.3 (NRS 6.6-4.3) and 2.2 (NRS 6.8-4.6) points, respectively, when comparing the long-term data with baseline. Moreover, for > 50% of patients, the pain reduction was > 30%, which is considered clinically meaningful. No differences were found regarding the secondary outcomes. CONCLUSION: This eight-to-ten-year follow-up study indicates that SCS can remain an effective treatment in the long term to reduce pain intensity in a subcohort of patients with PDPN who still had an SCS device implanted after eight years.

'What you suggest is not what I expected': How pre-consultation expectations affect shared decision-making in patients with low back pain.

OBJECTIVE: Existing studies on shared decision-making (SDM) have hardly taken into consideration that patients could have independently developed expectations prior to their consultation with a healthcare provider, nor have studies explored how such expectations affect SDM. Therefore, we explore how pre-consultation expectations affect SDM in patients with low back pain. METHODS: We performed a qualitative study through telephone interviews with 10 patients and seven care professionals (physicians, nurse, physician assistants) and 63 in-person observations of patient-physician consultations in an outpatient clinic in the Netherlands. Transcripts were analyzed through an open coding process. RESULTS: A discrepancy existed between what patients expected and what care professionals could offer. Professionals perceived they had to undertake additional efforts to address patients' 'unrealistic' expectations while attempting SDM. Patients, in turn, were often dissatisfied with the outcomes of the SDM encounter, as they believed their own expectations were not reflected in the final decision. CONCLUSION: Unaddressed pre-consultation expectations form a barrier to constructive SDM encounters. PRACTICAL IMPLICATIONS: Patients' pre-consultation expectations need to be explored during the SDM encounter. To achieve decisions that are truly shared by care professionals and patients, patients' pre-consultation expectations should be better incorporated into SDM models and education.

Do Men and Women Have a Different Association between Fear-Avoidance and Pain Intensity in Chronic Pain? An Experience Sampling Method Cohort-Study.

BACKGROUND: Fear-avoidance is one of the factors associated with chronic pain. However, it remains unclear whether the association between fear-avoidance and pain depends on sex. The present study aimed to investigate whether the association between fear-avoidance and pain intensity differed between men and women in chronic pain patients. Additionally, the potential confounding effect of affective experiences on the association between fear-avoidance and pain intensity was analyzed. METHOD: This cohort study included hospital referred chronic pain patients (n = 45). Short momentary assessment questions according to the experience sampling method (ESM) were used to repeatedly assess patients' pain intensity, level of fear-avoidance and positive as well as negative affect during their daily life. Linear mixed-effects models were applied in the statistical analysis. Unadjusted and adjusted models were made, in which the latter corrected for statistically significant affective experiences and baseline variables, taking the Aikake Information Criterion into account to assess a better model of fit. RESULTS: The results demonstrated an association between fear-avoidance and pain intensity that differed for men and women. In men (n = 13), no association between these variables was found (-0.04 (95% CI: -0.14, 0.06) with a p-value of 0.48), whereas in women (n = 32), an increase in fear-avoidance was associated with a (slight) increase in pain intensity (0.18 (95% CI 0.06, 0.30) with a p-value of 0.003). Affect did not confound the above-mentioned findings. CONCLUSION: Our data supports previous research highlighting the importance of sex differences in pain experience. These findings may be relevant for clinicians to consider more personalized (i.e., gender specific) pain management in chronic pain patients.

Clinical important improvement of chronic pain patients in randomized controlled trials and the DATAPAIN cohort.

BACKGROUND: Change on the Numeric Rating Scale (NRS) is based on subjective pain experience, hampering the establishment of clinically important improvement. An anchor-based method, the Patients' Global Impression of Change (PGIC), is often added to determine whether a patient has improved. A two-point change on the NRS has been shown to be equivalent to a moderate clinically important improvement in randomized controlled trials (RCT's) on medication effects. We contemplated whether these findings could be reproduced in cohort and data and in non-drug interventional RCT's. METHODS: The NRS change was quantified by subtracting the NRS of baseline from the NRS at 6-month follow-up. Categorization of success/nonsuccess was applied on the PGIC, and their average NRS raw changes were calculated. The Spearman correlation coefficient quantified the overall relationship, while the discriminative ability was explored through the receiver operating characteristic curve. Data were stratified on design, sex, and pain intensity at baseline. Besides, the cohort evaluated treatment status at follow-up. RESULTS: The records of 1661 patients were examined. Overall, the observed NRS change needed for moderate clinically important improvement was larger than the average two points. Yet, the changes in the cohort were smaller compared with the RCT's. Moreover, it modified with pain intensity at baseline and treatment statuses indicated differences in mean clinical importance of -4.15 (2.70) when finalized at 6 months and -2.16 (2.48) when treatment was ongoing. CONCLUSION: The moderate clinically important improvement varied substantially, representing heterogeneity in pain relief and its relation to treatment success in chronic pain patients.

Efficacy and Long-term Effect of Radiofrequency Denervation in Patients with Clinically Diagnosed Cervical Facet Joint Pain: A Double-blind Randomized Controlled Trial.

STUDY DESIGN: Multicenter double-blind randomized sham-controlled trial. OBJECTIVE: To assess the efficacy of radiofrequency (RF) denervation of the cervical facet joints in chronic cervical facet joint pain. SUMMARY OF BACKGROUND DATA: One randomized controlled trial showed efficacy of RF denervation in whiplash-associated disease. There are no randomized controlled trials on RF denervation in patients with chronic cervical facet joint pain. METHODS: Patients were randomized to receive RF denervation combined with bupivacaine (intervention group) or bupivacaine alone (control group). In the intervention group, an RF thermal lesion was made at the cervical medial branches after the injection of bupivacaine. The primary outcome was measured at 6 months and consisted of pain intensity, self-reported treatment effect, improvement on the Neck Disability Index, and the use of pain medication. Duration of effect was determined using telephone interviews. RESULTS: We included 76 patients. In the intervention group, 55.6% showed > 30% pain decrease versus 51.3% in the control group (P = 0.711); 50.0% reported success on the Patients' Global Impression of Change in the intervention group versus 41.0% (P = 0.435); the Neck Disability Index was 15.0 ±â€Š8.7 in the intervention group compared with 16.5 ±â€Š7.2 (P = 0.432), the need for pain medication did not differ significantly between groups (P = 0.461). The median time to end of treatment success for patients in the RF group was 42 months, compared with 12 months in the bupivacaine group (P = 0.014). CONCLUSIONS: We did not observe significant differences between RF denervation combined with injection of local anesthesia compared with local anesthesia only at 6 months follow-up. We found a difference in the long-term effect after 6 months follow-up in favor of the RF treatment.Level of Evidence: 2.

Biopsychosocial baseline values of 15 000 patients suffering from chronic pain: Dutch DataPain study.

BACKGROUND AND OBJECTIVES: Chronic pain affects many adults. To improve our daily practice, we need to understand multidisciplinary approaches, integrated treatment plans and the biopsychosocial context of these patients. To date, almost 15 000 chronic pain patients have been referred to the Maastricht University Pain Center in the Netherlands. METHODS: This study describes 11 214 of these patients suffering from chronic pain. Chronic pain was analyzed using relevant Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials instruments. RESULTS: Most patients were female (59.3%). The prevalence of low education was 59%, and unemployment/disability was 35.9%. The mean age was 55.6 years. Severe pain (Numerical Rating Sale score 7-10) was reported by 71.9% of the patients; psychological and quality of life values deteriorated when pain severity increased. Approximately 36% of patients showed severe signs of depression or anxiety, and 39% displayed high pain catastrophizing. Of all patients, 17.8% reported high values for pain severity, catastrophizing and anxiety or depression. CONCLUSIONS: Based on baseline biopsychosocial values, this study shows the complexity of patients referred to pain centers. Pain management with a biopsychosocial approach in an integrated multidisciplinary setting is indispensable. Above all, adjusted education on chronic pain and attention to its biopsychosocial aspects are deemed necessary.

Quality indicators to assess quality of pain clinic care from the perspective of patients with chronic pain: development, usability, comprehensibility, and psychometric quality of the QiPPP questionnaire.

To address the lack of appropriate patient-defined quality indicators (QIs) for assessment of pain clinic care in the Netherlands, we developed the "Quality Indicators Pain Patients' Perspective" (QiPPP) questionnaire. Quality indicators are widely used to measure the quality of the structure, process, and outcome of health care. The Pain Patient United Consortium, together with the University Pain Centre of Maastricht, developed QIs for assessment of care. The aim of this study was to develop QIs from the perspective of patients with chronic pain for assessment of the care provided by a pain clinic, and to validate them on usability, comprehensibility, and psychometric quality in daily pain practice. Quality as defined by patients with chronic pain (in survey and focus groups) was prioritized by consensus and transformed into QI. A first set was tested and fine-tuned, resulting in the QiPPP questionnaire. Five participating pain clinics distributed 200 questionnaires among consecutive patients with chronic pain under treatment. To examine the dimensionality of the QIs, patient responses were analyzed on the basis of reporting frequencies and findings of principal component analysis. For construct validation, the influence of patient characteristics was observed in 3 components. A total of 547 (54.7%) populated QiPPP questionnaires (response rate, 58.9%) were analyzed. The mean score for patient comprehensibility was 8.6 ± 1.4. The final QiPPP questionnaire included 21 QIs (18 process; 3 outcome) distributed over 7 domains. The QiPPP questionnaire was of sufficient psychometric quality and found to be useful and understandable by patients with chronic pain.

Developing a core outcome domain set to assessing effectiveness of interdisciplinary multimodal pain therapy: the VAPAIN consensus statement on core outcome domains.

Interdisciplinary multimodal pain therapy (IMPT) is a biopsychosocial treatment approach for patients with chronic pain that comprises at least psychological and physiotherapeutic interventions. Core outcome sets (COSs) are currently developed in different medical fields to standardize and improve the selection of outcome domains, and measurement instruments in clinical trials, to make trial results meaningful, to pool trial results, and to allow indirect comparison between interventions. The objective of this study was to develop a COS of patient-relevant outcome domains for chronic pain in IMPT clinical trials. An international, multiprofessional panel (patient representatives [n = 5], physicians specialized in pain medicine [n = 5], physiotherapists [n = 5], clinical psychologists [n = 5], and methodological researchers [n = 5]) was recruited for a 3-stage consensus study, which consisted of a mixed-method approach comprising an exploratory systematic review, a preparing online survey to identify important outcome domains, a face-to-face consensus meeting to agree on COS domains, and a second online survey (Delphi) establishing agreement on definitions for the domains included. The panel agreed on the following 8 domains to be included into the COS for IMPT: pain intensity, pain frequency, physical activity, emotional wellbeing, satisfaction with social roles and activities, productivity (paid and unpaid, at home and at work, inclusive presentism and absenteeism), health-related quality of life, and patient's perception of treatment goal achievement. The complexity of chronic pain in a biopsychosocial context is reflected in the current recommendation and includes physical, mental, and social outcomes. In a subsequent step, measurement instruments will be identified via systematic reviews.

Predictive Factors for Successful Outcome of Pulsed Radiofrequency Treatment in Patients with Intractable Lumbosacral Radicular Pain.

BACKGROUND: In a previous prospective study on pulsed radiofrequency (PRF) treatment adjacent to the lumbar dorsal root ganglion (DRG) for patients with chronic lumbosacral radicular pain, we reported success in 55.4% of the patients at 6 months. Identification of predictors for success after PRF may improve outcome. We assessed the predictors of PRF in patients with chronic intractable lumbosacral radicular pain. METHODS: Patients with monosegmental chronic lumbosacral radicular pain of L5 or S1 first received a selective nerve root block at the corresponding level. Independent of the result of this block a PRF treatment at the same level was performed. At 6 weeks, 3 months, and 6 months after the procedure the outcome was evaluated. RESULTS: A positive diagnostic nerve root block and age ≥ 55 were predictive factors for successful outcome at 6 months, while disability was a negative predictor.The use of failed back surgery syndrome, gender, duration of pain, Numerical Rating Scale, level and side of treatment, DN4, and RAND-36 as predictors for success was not supported. CONCLUSIONS: Successful outcome after PRF adjacent to the DRG, in patients with intractable chronic lumbosacral radicular pain, is more likely in patients ≥ 55 years, with limited disability and after a positive diagnostic nerve root block. A combination of all these factors creates a fair predictive value (AUC: 0.73).

First Dutch Consensus of Pain Quality Indicators for Pain Treatment Facilities.

BACKGROUND: There is a general consensus about the need to define and improve the quality of pain treatment facilities. Although guidelines and recommendations to improve the quality of pain practice management have been launched, provision of appropriate pain treatment is inconsistent and the quality of facilities varies widely. The aim of the study was to develop an expert-agreed list of quality indicators applicable to pain treatment facilities. The list was also intended to be used as the basis for a set of criteria for registered status of pain treatment facilities. METHODS: The University Pain Center Maastricht at the Department of Anesthesiology and Pain Management of the Maastricht University Medical Center conducted a 3-round Delphi study in collaboration with the Board of the Pain Section of the Dutch Society of Anesthesiologists (NVA). RESULTS: Twenty-five quality indicators were selected as relevant to 2 types of pain treatment facilities, pain clinics and pain centers. The final expert-agreed list consisted of 22 quality indicators covering 7 quality domains: supervision, availability of care, staffing level and patient load, quality policy, multidisciplinarity, regionalization, and research and education. CONCLUSIONS: This set of quality indicators may facilitate organizational evaluation and improve insight into service quality from the perspectives of patients, pain specialists, and other healthcare professionals. Recommendations for improvements to the current set of quality indicators are made. In 2014 the process of registering pain treatment facilities in the Netherlands started; facilities can register as a pain clinic or pain center.

Pulsed radiofrequency for chronic intractable lumbosacral radicular pain: a six-month cohort study.

BACKGROUND AND OBJECTIVES: There is little evidence concerning the medical management of lumbosacral radicular pain. The prognosis for patients suffering pain for more than 3 months is poor. Pulsed radiofrequency (PRF) treatment of the dorsal root ganglion (DRG) has been suggested as a minimally invasive treatment. We studied the effect on pain and quality of life of PRF treatment of the DRG in patients with chronic, severe lumbosacral radicular pain. METHODS: Patients with lumbosacral radicular pain were screened to select a homogeneous population. PRF treatment of the DRG was performed at L5 or S1. Evaluation was carried out at 6 weeks, 3 months, and 6 months. Pain reduction and "fully recovered" or "much improvement," in terms of the global perceived effect, were the primary outcomes. Quality of life (RAND-36), disability (Oswestry Disability Index), and the neuropathic pain scales leeds assessment of neuropathic symptoms and signs (LANSS) and DN4 were registered at each time point. Medication use was scored with the Medication Quantification Scale. RESULTS: Out of 461 screened patients, 65 were included. According to the intention to treat analysis, clinical success was achieved in 56.9%, 52.3%, and 55.4% of the patients at respectively 6 weeks, 3 months, and 6 months. DN4, Oswestry Disability Index and physical component for the RAND-36 quality of life improved significantly while the mental component remained unchanged. The number of patients on opioids was reduced. CONCLUSIONS: PRF treatment of the DRG may be considered for patients with chronic, severe lumbosacral radicular pain refractory to conventional medical management.

Pain treatment facilities: do we need quantity or quality?

RATIONALE, AIMS AND OBJECTIVES: Chronic pain patients referred to a pain treatment facility have no guarantee that they will receive a proper diagnostic procedure or treatment. To obtain information about organizational aspects of pain treatment facilities and the content of their daily pain practice, we performed a questionnaire survey. The aim of the study was to evaluate the amount of pain treatment facilities, the content of organized specialized pain care and adherence to the criteria of the internationally accepted guidelines for pain treatment services. METHOD: The University Pain Centre Maastricht in the Department of Anaesthesiology and Pain Management at Maastricht University Medical Centre developed a questionnaire survey based on the Recommendations for Pain Treatment Services of the International Association for the Study of Pain (IASP). The questionnaire was sent to the medical boards of all hospitals in the Netherlands (n=94). RESULTS: The response rate was 86% (n=81). Of all hospitals, 88.9% (n=72) reported the provision of organized specialized pain care, which was provided by a pain management team in 86.1% (n=62) and by an individual specialist in 13.9% (n=10). Insight was obtained from pain treatment facilities in five different domains: the organizational structure of pain management, composition of the pain team, pain team practice, patient characteristics, and research and education facilities. CONCLUSION: Although 88.9% of all hospitals stated that organized specialized pain care was provided, only a few hospitals could adhere to the criteria for pain treatment services of the IASP. The outcome of the questionnaire survey may help to define quality improvement standards for pain treatment facilities.

Long-term follow-up of cervical facet medial branch radiofrequency treatment with the single posterior-lateral approach: an exploratory study.

BACKGROUND: Over 50% of patients presenting to pain clinic with neck pain have the cervical facet joints as the source of pain. Radiofrequency (RF) treatment of the medial branch, innervating the facet joint, is a therapeutic option. The objectives of this study were to evaluate the therapeutic effect and its duration of RF treatment, using the single posterior-lateral approach in patients suffering from facet joint degeneration and to identify predictors for a long-term effect. METHODS: Of the 130 consecutive patients with axial neck pain referred to the University Pain Center Maastricht, 67 fulfilled the inclusion criteria. The therapeutic effect was measured using the Patients' Global Impression of Change (PGIC) scale. Retrospective data were made complete using newly collected PGIC follow-up data. A Kaplan-Meier curve evaluated the long-term therapeutic effect. Possible predictors of outcome were evaluated. RESULTS: Two patients refused to participate and in the remaining 65 patients, overall pain relief was reported in 55.4% at 2-month follow-up. Moderately, important change of improvement and substantial change of improvement were seen in 50.8% of patients. At 3-year follow-up, 30% still reported pain reduction. Spinal treatment level was the only predictor found. CONCLUSIONS: Radiofrequency treatment of the cervical facet joints using a single posterior-lateral approach is a promising technique in patients with chronic neck pain due to facet degeneration. The short-term and long-term therapeutic effects of this intervention justify a randomized controlled trial to estimate the efficacy of cervical facet joint RF treatment in a chronic neck pain population.

Pulsed radiofrequency treatment adjacent to the lumbar dorsal root ganglion for the management of lumbosacral radicular syndrome: a clinical audit.

INTRODUCTION: Lumbosacral radicular syndrome (LRS) is probably the most frequent neuropathic pain syndrome. Three months to 1 year after onset, 30% of the patients still experience ongoing pain. The management of those patients is complex, and treatment success rates are rather low. The beneficial effect of pulsed radiofrequency (PRF) therapy has been described for the treatment of LRS in case reports and in retrospective and prospective studies. Up until now, no neurological complications have been reported after PRF treatment. The current clinical audit has been performed to assess the amount of pain relief after a single PRF treatment. METHODS: Sixty consecutive patients who received a PRF treatment adjacent to the lumbar dorsal root ganglion for the management of LRS in the period 2007-2009 were included. The main study objective was to measure the reduction of pain after the pulsed radiofrequency treatment by using the global perceived effect. The primary end point was defined as at least 50% pain relief for a period of 2 months or longer. RESULTS: The primary end point was achieved in 29.5% of all the PRF interventions. After 6 months, 50% pain relief was still present in 22.9% of the cases and after 12 months in 13.1% of the cases. The need for pain medication was significantly lower after pulsed radiofrequency treatment in the success group compared with the nonsuccess group. CONCLUSIONS: PRF treatment can be considered for the management of LRS patients. These results need to be confirmed in a randomized clinical trial.