Marten van Wijhe

Illness perceptions in patients with fibromyalgia and their relationship to quality of life and catastrophizing

OBJECTIVE In the last decade, illness perceptions have been identified as important in the treatment of fibromyalgia (FM). The aim of the present study was to examine illness perceptions and use of the revised Illness Perception Questionnaire in patients with FM (IPQ-R-FM) and their relationship to quality of life and catastrophizing. METHODS A domain with specific causal attributions related to FM was added to the IPQ-R-FM. The psychometric properties of the IPQ-R-FM dimensions and attribution scales were examined. The causal domain, in which patients describe the most important perceived causes for their FM, was analyzed. To analyze the relationship with quality of life and catastrophizing, the Fibromyalgia Impact Questionnaire and the Pain Catastrophizing Scale were used. RESULTS Fifty-one outpatients completed the questionnaires on 2 occasions, 3 weeks apart. FM was considered to be chronic and to have serious consequences; patients perceived little personal control and did not expect medical treatment to be effective. The psychometric properties of the IPQ-R-FM were found to be adequate. Patients most frequently attributed the causes of FM to an external somatic source (58%). Quality of life was related to experiencing more consequences attributable to FM. Catastrophizing was related to a limited understanding of the symptoms of FM, the more cyclical nature of FM, and an emotional representation. CONCLUSION The IPQ-R-FM is a useful tool to assess illness perceptions in patients with FM. Illness perceptions are related to quality of life and catastrophizing; therefore, it seems important to assess and integrate illness perceptions into the management of patients with FM.

Bilateral sensory abnormalities in patients with unilateral neuropathic pain; a quantitative sensory testing (QST) study.

In patients who experience unilateral chronic pain, abnormal sensory perception at the non-painful side has been reported. Contralateral sensory changes in these patients have been given little attention, possibly because they are regarded as clinically irrelevant. Still, bilateral sensory changes in these patients could become clinically relevant if they challenge the correct identification of their sensory dysfunction in terms of hyperalgesia and allodynia. Therefore, we have used the standardized quantitative sensory testing (QST) protocol of the German Research Network on Neuropathic Pain (DFNS) to investigate somatosensory function at the painful side and the corresponding non-painful side in unilateral neuropathic pain patients using gender- and age-matched healthy volunteers as a reference cohort. Sensory abnormalities were observed across all QST parameters at the painful side, but also, to a lesser extent, at the contralateral, non-painful side. Similar relative distributions regarding sensory loss/gain for non-nociceptive and nociceptive stimuli were found for both sides. Once a sensory abnormality for a QST parameter at the affected side was observed, the prevalence of an abnormality for the same parameter at the non-affected side was as high as 57% (for Pressure Pain Threshold). Our results show that bilateral sensory dysfunction in patients with unilateral neuropathic pain is more rule than exception. Therefore, this phenomenon should be taken into account for appropriate diagnostic evaluation in clinical practice. This is particularly true for mechanical stimuli where the 95% Confidence Interval for the prevalence of sensory abnormalities at the non-painful side ranges between 33% and 50%.

Chronic pain and severe disuse syndrome : long-term outcome of an inpatient multidisciplinary cognitive behavioural programme

OBJECTIVE Patients with chronic pain and severe disuse syndrome have pain with physiological, psychological and social adaptations. The duration and severity of complaints, combined with previously failed treatments, makes them unsuitable for treatment in primary care. DESIGN A prospective waiting list controlled study. PATIENTS A total of 32 patients with chronic pain for at least one year and severe disuse syndrome were included in an inpatient multidisciplinary cognitive behavioural treatment. METHODS Patients were assessed before the waiting list period, before the clinical phase, after the clinical phase and after follow-ups of 6 months and one year. The visual analogue scale for pain and fatigue were assessed. Muscle strength of the arms and legs, arm endurance and a 6-minute walking test were used to assess physical outcome. The Symptom Checklist-90, RAND-36, pain cognition list and the Tampa scale for kinesiophobia were used to assess psychological outcome. RESULTS Long-term significant (p < 0.001) improvements were found for pain, fatigue, walking distance, muscle strength, anxiety, depression, somatization, negative self-efficacy, and catastrophizing in the intervention period. CONCLUSION An inpatient multidisciplinary cognitive behavioural programme is beneficial for patients with chronic pain and a severe disuse syndrome.

Heart Rate Variability Parameters Do Not Correlate with Pain Intensity in Healthy Volunteers

OBJECTIVE When patients cannot indicate pain, physiological parameters may be useful. We tested whether heart rate variability (HRV) parameters, as reflection of sympathetic and vagal tone, can be used to quantify pain intensity. DESIGN Prospective study. SUBJECTS AND SETTING A standardized heat stimulus was applied to the forearm in 75 healthy volunteers during three study periods of 2 minutes. METHODS Before and after each application, pain intensity was measured by a visual analog scale (VAS) and inter beat interval (IBI) was recorded. Standard deviation of normal to normal beat intervals (SDNN) of the IBI, the power of the low (LF, 0.07-0.14 Hz) and high frequency (HF, 0.15-0.50 Hz) band, and LF/HF ratio were calculated. Log transformation resulted in normal distribution. Correlation between HRV parameters and pain intensity was assessed by Pearsons correlation coefficient. RESULTS Data from 73 volunteers (44 women) could be analyzed. The mean age was 30 ± 11 years. Compared with baseline, during all heat periods, pain intensity measured by VAS increased from 2 ± 3 mm, 3 ± 5 mm, and 2 ± 4 mm, to 40 ± 20 mm, 42 ± 21 mm, and 44 ± 22 mm, respectively. Log transformed SDNN (lnSDNN) and LF (lnLF) decreased; lnSDNN from 4.0 ± 0.4 to 3.9 ± 0.5, P = 0.002; 4.0 ± 0.4 to 3.9 ± 0.5, P = 0.016; and 4.1 ± 0.4 to 3.9 ± 0.4, P = 0.004, respectively; lnLF from 6.3 ± 1.0 to 6.1 ± 1.2, P = 0.001; 6.4 ± 1.0 to 6.2 ± 1.1, P = 0.019; and 6.5 ± 1.0 to 6.2 ± 1.1, P = 0.020, respectively. No correlation of any HRV parameter with VAS score was found. CONCLUSION HRV parameters may detect responses to heat pain, but are not suitable to assess pain intensity.

Radiating low back pain in general practice: incidence, prevalence, diagnosis, and long-term clinical course of illness.

Abstract Objective. The aim of this study was to calculate the incidence and prevalence of radiating low back pain, to explore the long-term clinical course of radiating low back pain including the influence of radiculopathy (in a subsample of the study population) and non-radiating low back pain thereon, and to describe general practitioners’ (GPs’) treatment strategies for radiating low back pain. Design. A historic prospective cohort study. Setting. Dutch general practice. Subjects. Patients over 18 years of age with a first episode of radiating low back pain, registered by the ICPC code L86. Main outcome measures. Incidence and prevalence, clinical course of illness, initial diagnoses established by the GPs, and treatment strategies. Results. Mean incidence was 9.4 and mean prevalence was 17.2 per 1000 person years. In total, 390 patients had 1193 contacts with their GPs; 50% had only one contact with their GP. Consultation rates were higher in patients with a history of non-radiating low back pain and in patients with a diagnosis of radiculopathy in the first five years. In this studys subsample of 103 patients, L86 episodes represented radiculopathy in 50% of cases. Medication was prescribed to 64% of patients, mostly NSAIDs. Some 53% of patients were referred, mainly to physiotherapists and neurologists; 9% of patients underwent surgery. Conclusion. Watchful waiting seems to be sufficient general practice care in most cases of radiating low back pain. Further research should be focused on clarifying the relationship between radicular radiating low back pain, non-radicular radiating low back pain, and non-radiating low back pain.

A Novel Magnetic Stimulator Increases Experimental Pain Tolerance in Healthy Volunteers - A Double-Blind Sham-Controlled Crossover Study

The ‘complex neural pulse’TM (CNP) is a neuromodulation protocol employing weak pulsed electromagnetic fields (PEMF). A pioneering paper reported an analgesic effect in healthy humans after 30 minutes of CNP-stimulation using three nested whole head coils. We aimed to devise and validate a stimulator with a novel design entailing a multitude of small coils at known anatomical positions on a head cap, to improve applicability. The main hypothesis was that CNP delivery with this novel device would also increase heat pain thresholds. Twenty healthy volunteers were enrolled in this double-blind, sham-controlled, crossover study. Thirty minutes of PEMF (CNP) or sham was applied to the head. After one week the other treatment was given. Before and after each treatment, primary and secondary outcomes were measured. Primary outcome was heat pain threshold (HPT) measured with thermal quantitative sensory testing. Other outcomes were warmth detection threshold, and aspects of cognition, emotion and motor performance. As hypothesized heat pain threshold was significantly increased after the PEMF stimulation. All other outcomes were unaltered by the PEMF but there was a trend level reduction of cognitive performance after PEMF stimulation as measured by the digit-symbol substitution task. Results from this pilot study suggest that our device is able to stimulate the brain and to modulate its function. This is in agreement with previous studies that used similar magnetic field strengths to stimulate the brain. Specifically, pain control may be achieved with PEMF and for this analgesic effect, coil design does not appear to play a dominant role. In addition, the flexible configuration with small coils on a head cap improves clinical applicability. Trial Registration Dutch Cochrane Centre NTR1093

Fear of movement in pre-operative patients with a lumbar stenosis and or herniated disc: Factor structure of the Tampa scale for kinesiophobia

The presence of fear of movement is related to higher disability rates in several patient groups. The purpose of this study was first to analyze fear of movement and the relation with pain and disability in pre-operative patients with low back pain and radiculopathy and secondly to analyze the factor structure of the Dutch version of the Tampa Scale for Kinesiophobia (TSK). The TSK and Pain Disability Index (PDI) were assessed in 128 patients. An explorative factor analysis (EFA) and a confirmatory factor analysis (CFA) of the TSK were performed using Structural Equation Models (SEMs). Fear of movement was significantly related to leg-pain and pain disability. A four-factor model had an explained variance of 49%. After further analyses a solution with three factors (harm, somatic focus, activity avoidance) and nine items (1, 3, 6, 7, 9, 11, 14, 15, 17) had the best fit. Based on the content of this study clinically a factor structure with three subscales with nine items is favorable for usage in pre-operative patients with low back pain and radiculopathy.

Somatosensory Profiles but Not Numbers of Somatosensory Abnormalities of Neuropathic Pain Patients Correspond with Neuropathic Pain Grading

Due to the lack of a specific diagnostic tool for neuropathic pain, a grading system to categorize pain as ‘definite’, ‘probable’, ‘possible’ and ‘unlikely’ neuropathic was proposed. Somatosensory abnormalities are common in neuropathic pain and it has been suggested that a greater number of abnormalities would be present in patients with ‘probable’ and ‘definite’ grades. To test this hypothesis, we investigated the presence of somatosensory abnormalities by means of Quantitative Sensory Testing (QST) in patients with a clinical diagnosis of neuropathic pain and correlated the number of sensory abnormalities and sensory profiles to the different grades. Of patients who were clinically diagnosed with neuropathic pain, only 60% were graded as ‘definite’ or ‘probable’, while 40% were graded as ‘possible’ or ‘unlikely’ neuropathic pain. Apparently, there is a mismatch between a clinical neuropathic pain diagnosis and neuropathic pain grading. Contrary to the expectation, patients with ‘probable’ and ‘definite’ grades did not have a greater number of abnormalities. Instead, similar numbers of somatosensory abnormalities were identified for each grade. The profiles of sensory signs in ‘definite’ and ‘probable’ neuropathic pain were not significantly different, but different from the ‘unlikely’ grade. This latter difference could be attributed to differences in the prevalence of patients with a mixture of sensory gain and loss and with sensory loss only. The grading system allows a separation of neuropathic and non-neuropathic pain based on profiles but not on the total number of sensory abnormalities. Our findings indicate that patient selection based on grading of neuropathic pain may provide advantages in selecting homogenous groups for clinical research.

Epidural steroids for lumbosacral radicular syndrome compared to usual care: quality of life and cost utility in general practice.

OBJECTIVE To investigate the effect of adding segmental epidural steroid injections (SESIs) to usual care compared with usual care alone on quality of life and cost utility in lumbosacral radicular syndrome (LRS) in general practice. DESIGN A pragmatic randomized controlled trial. Results were analyzed using mixed models. SETTING Primary care. PARTICIPANTS Patients (N=50) in the acute phase of LRS. INTERVENTIONS One epidural injection containing 80mg of triamcinolone in normal saline. MAIN OUTCOME MEASURE Back pain at 4 weeks after the start of the treatment. RESULTS Both groups experienced a significant increase in quality of life in (especially) the physical domains of the Medical Outcomes Study 36-Item Short-Form Health Survey. The intervention group scored significantly better than the control group at certain time points in the physical domain. The differences were small. The cost-utility analysis showed that with a negligible loss of utility (3d in perfect health), societal costs (193,354 euros per quality-adjusted life year lost) would be saved because of more productivity in the intervention group. CONCLUSIONS Although the beneficial effects of SESIs are small and the natural course of LRS is predominantly favorable, we think decision makers can consider implementing SESIs in daily practice with the purpose of saving resources. Caution must be taken, and further research should be directed at identifying patient subgroups who might benefit from SESIs, with additional focus on (costs of) complications and adverse effects.

Costs and Cost-effectiveness of Epidural Steroids for Acute Lumbosacral Radicular Syndrome in General Practice An Economic Evaluation Alongside a Pragmatic Randomized Control Trial

Study Design. A pragmatic, randomized, controlled, single-blinded trial in Dutch general practice. Objective. Assessing the costs and cost-effectiveness of adding segmental epidural steroid injections to care as usual in radiculopathy in general practice. Summary of Background Data. Lumbosacral radicular syndrome (radiculopathy) is a benign, generally self-limiting but painful condition caused by a herniated lumbar intervertebral disc, which results in an inflammatory process around the nerve root. Segmental epidural steroid injections could lessen pain. Low back pain and sciatica form a large financial burden on national health care systems. Improving pain treatment could lower costs to society by diminishing loss of productivity. Methods. Patients with acute radiculopathy were included by general practitioners. All patients received usual care. Patients in the intervention group received one segmental epidural steroid injection containing 80 mg of triamcinolone as well. Follow-up was performed using postal questionnaires at 2, 4, 6, 13, 26, and 52 weeks. Main outcomes were pain, disability and costs. Economic evaluation was performed from a societal perspective with a time horizon of 1 year. Results. Sixty-three patients were included in the analysis. Mean total costs were &OV0556;4414 or