Neuropathic Pain Affects Quality of Life in Breast Cancer Survivors with Chemotherapy-Induced Peripheral Neuropathy.

BACKGROUND: Despite the significant impact of chemotherapy-induced peripheral neuropathy on the quality of life for breast cancer survivors, there is a notable lack of comprehensive research. Therefore, a crucial need exists for further systematic investigation and inquiry into this matter. AIMS: This study examined predictors of quality of life in breast cancer survivors with chemotherapy-induced peripheral neuropathy. DESIGN: A cross-sectional, correlational design. SETTINGS: This study was conducted at a medical center in northern Taiwan and a teaching hospital in northeastern Taiwan. PARTICIPANTS/SUBJECTS: One hundred and thirty adult women with breast cancer, who have undergone chemotherapy and obtained a Total Neuropathy Scale-Clinical Version score>0, were enrolled. METHODS: Neuropathic pain, sleep disturbances, depression, and quality of life were evaluated using multiple regression analysis to identify quality of life predictors. Clinical importance was established using the minimally important difference of Functional Assessment of Cancer Therapy-Breast. RESULTS: The study indicated that improving depression (B = -10.87, p < .001) and neuropathic pain (B = -8.33, p = .004) may enhance the quality of life of breast cancer survivors with chemotherapy-induced peripheral neuropathy. Moreover, the individual's marital status and family history of breast cancer were identified as predictive factors. CONCLUSIONS: This study illuminates quality of life determinants for breast cancer survivors with chemotherapy-induced peripheral neuropathy, advocating comprehensive care and addressing depression and neuropathic pain for better outcomes.

Mindfulness is associated with severity of peripheral neuropathy and related patient-reported outcomes among colorectal cancer patients.

PURPOSE: Despite the detrimental impact of chronic (chemotherapy-induced) peripheral neuropathy PN on patients' lives, treatment options remain limited. We examined the association between mindfulness and chronic PN symptom severity and impairments in related patient-reported outcomes (PROs) among colorectal cancer (CRC) patients up to 2 years after diagnosis. METHODS: Newly diagnosed stage I-IV CRC patients from four Dutch hospitals were eligible for participation. Patients (N = 336) completed a questionnaire on mindfulness (MAAS) at 1 year after diagnosis, and questionnaires on sensory (SPN) and motor peripheral neuropathy (MPN) (EORTC QLQ-CIPN20), anxiety and depressive symptoms (HADS), sleep quality (PSQI), and fatigue (EORTC QLQ-C30) before initial treatment (baseline) and 1 and 2 years after diagnosis. RESULTS: At 1-year follow-up, 115 patients (34%) and 134 patients (40%), respectively, reported SPN or MPN symptoms. In multivariable regression analyses, higher mindfulness at 1-year follow-up was associated with less severe MPN and fewer anxiety and depressive symptoms, better sleep quality, and less fatigue. Of the patients with SPN or MPN at 1-year follow-up, symptoms had not returned to baseline level at 2-year follow-up in 59 (51%) and 72 (54%) patients, respectively. In this subgroup, higher mindfulness was associated with less severe SPN and fewer anxiety symptoms, depressive symptoms, and fatigue at 2-year follow-up. CONCLUSION: Mindfulness was associated with less severe PN and better related PROs among CRC patients with chronic PN. More research is needed to examine the role of mindfulness in the transition from acute to chronic PN.

Yoga for cancer survivors with chemotherapy-induced peripheral neuropathy: Health-related quality of life outcomes.

BACKGROUND: Yoga is a meditative movement therapy focused on mind-body awareness. The impact of yoga on health-related quality of life (HRQOL) outcomes in patients with chemotherapy-induced peripheral neuropathy (CIPN) is unclear. METHODS: We conducted a pilot randomized wait-list controlled trial of 8 weeks of yoga (n = 21) versus wait-list control (n = 20) for CIPN in 41 breast and gynecological cancer survivors with persistent moderate to severe CIPN. HRQOL endpoints were Hospital Anxiety and Depression Scale (HADS), Brief Fatigue Inventory (BFI), and Insomnia Severity Index (ISI). The Treatment Expectancy Scale (TES) was administered at baseline. We estimated mean changes and 95% confidence intervals (CIs) from baseline to weeks 8 and 12 and compared arms using constrained linear mixed models. RESULTS: At week 8, HADS anxiety scores decreased -1.61 (-2.75, -0.46) in the yoga arm and -0.32 (-1.38, 0.75) points in the wait-list control arm (p = 0.099). At week 12, HADS anxiety scores decreased -1.42 (-2.57, -0.28) in yoga compared to an increase of 0.46 (-0.60, 1.53) in wait-list control (p = 0.017). There were no significant differences in HADS depression, BFI, or ISI scores between yoga and wait-list control. Baseline TES was significantly higher in yoga than in wait-list control (14.9 vs. 12.7, p = 0.019). TES was not associated with HADS anxiety reduction and HADS anxiety reduction was not associated with CIPN pain reduction. CONCLUSIONS: Yoga may reduce anxiety in patients with CIPN. Future studies are needed to confirm these findings. CLINICAL TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Identifier: NCT03292328.

Peripheral neuropathic pain.

Neuropathic pain (NP) can have either central nervous system causes or ones from the peripheral nervous system. This article will focus on the epidemiology, classifications, pathology, non-invasive treatments and invasive treatments as a general review of NP involving the peripheral nervous system. NP has characteristic symptomatology such as burning and electrical sensations. It occurs in up to 10% of the general population. Its frequency can be attributed to its occurrence in neck and back pain, diabetes and patients receiving chemotherapy. There are a wide range of pharmacologic options to control this type of pain and when such measures fail, numerous interventional methods can be employed such as nerve blocks and implanted stimulators. NP has a cost to the patient and society in terms of emotional consequences, quality of life, lost wages and the cost of assistance from the medical system and thus deserves serious consideration for prevention, treatment and control.

Effects of aroma self-foot reflexology on peripheral neuropathy, peripheral skin temperature, anxiety, and depression in gynaecologic cancer patients undergoing chemotherapy: A randomised controlled trial.

PURPOSE: Chemotherapy-induced peripheral neuropathy (CIPN) can interfere with activities of daily living and can negatively affect symptoms. Thus, this study aimed to develop and implement an aroma self-foot reflexology regimen based on Cox's Interaction Model of Client Health Behaviour (IMCHB) as an intervention that can be self-performed at home and at any time. The effects of aroma self-foot reflexology on peripheral neuropathy, peripheral skin temperature, anxiety, and depression were examined in patients with gynaecologic cancer who were undergoing chemotherapy. METHODS: This randomized controlled trial included 32 experimental and 31 control patients with CIPN. Data were collected using self-reported questionnaires (CIPN assessment tool, HADS). In the experimental group, peripheral neuropathy, peripheral skin temperature, anxiety, and depression were measured before and after aroma self-foot reflexology therapy for 6 weeks. The control group was provided with identical aroma self-foot reflexology training 6 weeks later and underwent the intervention at that time. RESULTS: The intervention resulted in lower levels of symptoms of peripheral neuropathy, less interference with activities (p < .001), and higher peripheral skin temperature level (p < .001). Anxiety and depression decreased in the experimental group (p < .001). The ratio of borderline and definite cases of anxiety and depression did not differ between groups. CONCLUSIONS: An aroma self-foot reflexology intervention can reduce CIPN, anxiety, and depression in gynaecologic cancer patients. Further research is required to assess the effects of differences in the content of the intervention and the effects of various numbers of applications and durations of applications based on each individual patient's condition.

Impact of Somatic Yoga and Meditation on Fall Risk, Function, and Quality of Life for Chemotherapy-Induced Peripheral Neuropathy Syndrome in Cancer Survivors.

OBJECTIVE: Chemotherapy-induced peripheral neuropathy (CIPN) syndrome causes significant pain as an adverse effect of treatment, with few nonpharmacological interventions tested. A somatic yoga and meditation (SYM) intervention on functional outcomes and quality of life (QOL) was investigated. DESIGN AND METHODS: Individuals diagnosed with CIPN were enrolled in an open-label, single-arm, mixed-methods feasibility trial. PARTICIPANTS AND SETTING: In an outpatient rehabilitation center, ten participants with median age 64.4 years (47-81) attended 61% of the sessions with no adverse events. INTERVENTION: SYM twice a week for 8 weeks for 1.5 hours, with home program and journaling. MAIN OUTCOME MEASURES: Primary functional outcomes included Sit and Reach (SR), Functional Reach (FR), and Timed Up and Go (TUG). Self-reported Patient Neurotoxicity Questionnaire (PNQ) and Functional Assessment of Cancer Therapy-Neurotoxicity (FACT-GOG-NTX) were secondary CIPN outcomes. Biomarkers included salivary cortisol (stress) and bioesthesiometer (vibration). RESULTS: Quantitative findings. Significant improvements were found in flexibility (SR; P = .006); balance (FR; P = .001) and fall risk (TUG; P = .004). PNQ improved significantly ( P = .003) with other measures improving non-significantly. Qualitative findings. Five themes emerged: (1) vacillation of CIPN pain perception over time; (2) transferability of skills to daily activities; (3) improvement in physical function; (4) perceived relaxation as an effect of SYM; and (5) group engagement provided a social context for not feeling isolated with CIPN. CONCLUSION: Preliminary data suggest SYM may improve QOL, flexibility, and balance in cancer survivors with CIPN, with a fully powered randomized controlled trial indicated. TRIAL REGISTRATION: NCT03786055.

Dissociable Contributions of Precuneus and Cerebellum to Subjective and Objective Neuropathy in HIV.

Neuropathy, typically diagnosed by the presence of either symptoms or signs of peripheral nerve dysfunction, remains a frequently reported complication in the antiretroviral (ART)-treated HIV population. This study was conducted in 109 healthy controls and 57 HIV-infected individuals to investigate CNS regions associated with neuropathy. An index of objective neuropathy was computed based on 4 measures: deep tendon ankle reflex, vibration sense (great toes), position sense (great toes), and 2-point discrimination (feet). Subjective neuropathy (self-report of pain, aching, or burning; pins and needles; or numbness in legs or feet) was also evaluated. Structural MRI data were available for 126/166 cases. The HIV relative to the healthy control group was impaired on all 4 signs of neuropathy. Within the HIV group, an objective neuropathy index of 1 (bilateral impairment on 1 measure) or 2 (bilateral impairment on at least 2/4 measures) was associated with older age and a smaller volume of the cerebellar vermis. Moderate to severe symptoms of neuropathy were associated with more depressive symptoms, reduced quality of life, and a smaller volume of the parietal precuneus. This study is consistent with the recent contention that ART-treated HIV-related neuropathy has a CNS component. Distinguishing subjective symptoms from objective signs of neuropathy allowed for a dissociation between the precuneus, a brain region involved in conscious information processing and the vermis, involved in fine tuning of limb movements. Graphical Abstract In HIV patients, objective signs of neuropathy correlated with smaller cerebellar vermis (red) volumes whereas subjective symptoms of neuropathy were associated with smaller precuneus (blue) volumes.

The evaluation of changes in peripheral neuropathy and quality-of-life using low-frequency electrostimulation in patients treated with chemotherapy for breast cancer: a study protocol.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a progressive, enduring, and sometimes irreversible neurotoxic symptom that occurs in 30-40% of chemotherapy-treated cancer patients. CIPN negatively affects both the patient's abilities to perform daily activities and their health-related quality of life (HRQOL) after chemotherapy treatment. Although this neuropathy has been treated with duloxetine and/or gabapentin, limited therapeutic benefits have been reported, thereby necessitating the development of an integrated approach that combines pharmacological management and complementary methods such as acupuncture and electric nerve stimulation. Therefore, this study is designed to examine the effect of a portable, low-frequency electrostimulation (ES) device on CIPN symptoms and HRQOL of female patients diagnosed with CIPN immediately after chemotherapy for breast cancer. METHODS: This study is a single-center, randomized, placebo-controlled trial with two parallel groups and a 2-week follow-up. We will enroll 80 breast cancer patients who are newly diagnosed with CIPN after chemotherapy. Duloxetine or pregabalin will be prescribed to all participants from the initial assessment. Half of the patients will be assigned into the experimental group and the other half to the control group. The CarebandR (Piomed Inc., Seoul, Korea), a wearable wristband that generates low-frequency electrostimulation, will be administered only to the experimental group. Electrostimulation will be administered on the unilateral PC6 acupoint. A numerical rating scale will be used to assess the overall intensity of CIPN symptoms. The key secondary outcome variables include patient-reported CIPN symptom distress tested by a self-rated questionnaire, physician-rated symptom severity assessed by the Total Neuropathy Score, and HRQOL. DISCUSSION: It is expected that the combination of a low-frequency electrostimulation device and pharmacological intervention (duloxetine or pregabalin) will produce synergistic effects in breast cancer patients with CIPN after treatment. To our knowledge, this is the first study to investigate the beneficial effect of a new integrated approach for CIPN management after breast cancer treatment. The study findings can expand our knowledge and understanding of the occurrence of CIPN and the efficacy of integrated intervention efforts to ameliorate CIPN symptoms. TRIAL REGISTRATION: Clinical Research Information Service (CRIS), Republic of Korea, ID: KCT0002357 . Registered retrospectively on 13 June 2017.

High dose subcutaneous immunoglobulin for idiopathic inflammatory myopathies and dysimmune peripheral chronic neuropathies treatment: observational study of quality of life and tolerance.

BACKGROUND: In patients with autoimmune diseases who still derive benefit from high dose intravenous immunoglobulin (IVIg) treatment, some physicians resort to subcutaneous (SC) Ig as a replacement therapy. OBJECTIVE: To collect quality of life (QoL) and tolerance data on SCIg in patients for whom the switch from IVIg to SCIg is essential to maintain treatment. METHODS: This observational study included patients with either idiopathic inflammatory myopathies (IIM) or chronic dysimmune peripheral neuropathies (CDPN) treated with IVIg, who had been switched to SCIg administration for at least three months. The main objective was to describe the impact of SCIg on QoL after six months, using the generic Short-Form 36 questionnaire (SF-36). The secondary objectives were to evaluate SCIg tolerance and clinical efficiency. RESULTS: Eight centres recruited 12 IIM patients and two centres recruited 11 CDPN patients. Neither the physical nor the mental health SF-36 component summaries showed any QoL deterioration during the six-month study period and all IIM and CDPN patients remained clinically stable during the same period. The most frequent adverse effects were injection site reactions (50%), cutaneous tissue disorders (18.2%), and nervous system disorders (13.6%). Two serious adverse events (myocarditis and cerebrovascular accident) occurred in two patients. CONCLUSION: In these rare inflammatory diseases, high dose SCIg administration (which can be home based) has no deleterious effect on patient QoL. It appears to be a safe and efficient alternative to hospital-based IVIg.

Improvement in Neuropathy Specific Quality of Life in Patients with Diabetes after Vitamin D Supplementation.

OBJECTIVE: To assess the effect of vitamin D supplementation on neuropathy specific quality of life (NeuroQoL) in patients with painful diabetic neuropathy. METHODS: This prospective, open label study was conducted between June 2012 and April 2013. Patients with symptomatic diabetic neuropathy were given a single dose of 600,000 IU intramuscular vitamin D, and NeuroQol was assessed at baseline and at five follow-up visits every 4 weeks. RESULTS: Of 143 participants, 41.3% were vitamin D deficient (vitamin D < 20 ng/ml). Treatment with vitamin D resulted in a significant increase in 25(OH)D (P < 0.0001) and a significant improvement in the NeuroQoL subscale score for emotional distress (P = 0.04), with no significant change in the other NeuroQoL domains of painful symptoms and paresthesia, loss of temperature and touch sensation, unsteadiness, limitation in daily activities, and interpersonal problems. There was a significant reduction in patient perception about foot problems on QoL of "quite a lot" (P < 0.05) and "very much" (P < 0.0001) with a significant reduction in the baseline response of having a "poor" QoL from 5.2% to 0.7% (P < 0.0001) and an increase in the response of an "excellent QoL" from 1.5% to 7.4% (P < 0.0001). CONCLUSION: Vitamin D is effective in improving quality of life in patients with painful diabetic neuropathy.

Complexity-based measures inform Tai Chi's impact on standing postural control in older adults with peripheral neuropathy.

BACKGROUND: Tai Chi training enhances physical function and may reduce falls in older adults with and without balance disorders, yet its effect on postural control as quantified by the magnitude or speed of center-of-pressure (COP) excursions beneath the feet is less clear. We hypothesized that COP metrics derived from complex systems theory may better capture the multi-component stimulus that Tai Chi has on the postural control system, as compared with traditional COP measures. METHODS: We performed a secondary analysis of a pilot, non-controlled intervention study that examined the effects of Tai Chi on standing COP dynamics, plantar sensation, and physical function in 25 older adults with peripheral neuropathy. Tai Chi training was based on the Yang style and consisted of three, one-hour group sessions per week for 24 weeks. Standing postural control was assessed with a force platform at baseline, 6, 12, 18, and 24 weeks. The degree of COP complexity, as defined by the presence of fluctuations existing over multiple timescales, was calculated using multiscale entropy analysis. Traditional measures of COP speed and area were also calculated. Foot sole sensation, six-minute walk (6MW) and timed up-and-go (TUG) were also measured at each assessment. RESULTS: Traditional measures of postural control did not change from baseline. The COP complexity index (mean ± SD) increased from baseline (4.1 ± 0.5) to week 6 (4.5 ± 0.4), and from week 6 to week 24 (4.7 ± 0.4) (p=0.02). Increases in COP complexity-from baseline to week 24-correlated with improvements in foot sole sensation (p=0.01), the 6MW (p=0.001) and TUG (p=0.01). CONCLUSIONS: Subjects of the Tai Chi program exhibited increased complexity of standing COP dynamics. These increases were associated with improved plantar sensation and physical function. Although more research is needed, results of this non-controlled pilot study suggest that complexity-based COP measures may inform the study of complex mind-body interventions, like Tai Chi, on postural control in those with peripheral neuropathy or other age-related balance disorders.

High-tone external muscle stimulation in endstage renal disease: effects on quality of life in patients with peripheral neuropathy.

OBJECTIVE: High-tone external muscle stimulation (HTEMS) has been shown to ameliorate painful peripheral neuropathy of dialysis patients. We hypothesized that HTEMS could also lead to improved parameters of health-related quality of life (HRQOL). METHODS: 25 end-stage renal disease (ESRD) patients (17 men/8 women, mean age 62.2 ± 14.2 years) were enrolled for the study. For evaluation of HRQOL the short form SF-36 was used. In addition, the Hospital Anxiety and Depression Scale (HADS) and the pain severity score were investigated. HTEMS was applied intradialytically for 1 hour, 3 times a week. Its effect was evaluated just before the beginning and both 6 and 12 weeks after onset of this study. RESULTS: SF-36 showed a significant effect of time for the subscales of physical role functioning and social functioning. A marginal significant positive trend could be observed for physical functioning. The pain symptom questionnaire sum scores improved significantly after 12 weeks. The HADS did not change significantly. CONCLUSION: The data indicate that intradialytic HTEMS treatment of ESRD patients with peripheral neuropathy ameliorates various components of physical health.

Characteristics of chronic pain associated with sleep difficulty in older adults: the Maintenance of Balance, Independent Living, Intellect, and Zest in the Elderly (MOBILIZE) Boston study.

OBJECTIVES: To evaluate pain severity and distribution in relation to sleep difficulty in older adults. DESIGN: Population-based cross-sectional study. SETTING: Community within a 5-mile radius of the study center at the Institute for Aging Research, Hebrew SeniorLife (HSL), Boston. PARTICIPANTS: Seven hundred sixty-five participants of the Maintenance of Balance, Independent Living, Intellect, and Zest in the Elderly (MOBILIZE) Boston Study aged 64 and older. MEASUREMENTS: Pain severity was measured using the Brief Pain Inventory (BPI) Pain Severity Subscale. Musculoskeletal pain distribution was grouped according to no pain, single site, two or more sites, and widespread pain (upper and lower extremities and back pain). Three aspects of sleep difficulty were measured using items from the Center for Epidemiologic Studies Depression Scale, Revised (trouble getting to sleep, sleep more than usual, and restless sleep). RESULTS: Prevalence of trouble getting to sleep according to BPI severity was 17.8%, 19.7%, 32.0%, and 37.0% for the lowest to highest pain severity quartiles, respectively. Similar relationships between pain and sleep were observed across sleep measures according to pain severity and distribution. Adjusted for sociodemographic characteristics, chronic conditions, and health behaviors, chronic pain was strongly associated with trouble sleeping (≥ 1 d/wk) (single-site pain, odds ratio (OR)=1.77, 95% confidence interval (CI)=1.10-2.87; multisite pain, OR=2.38, 95% CI=1.48-3.83; widespread pain, OR=2.55, 95% CI=1.43-4.54, each compared with no pain). Similar associations were observed for restless sleep and sleeping more than usual. For specific pain sites alone or in combination with other sites of pain, only modest associations were observed with sleep problems. CONCLUSION: Widespread or other multisite pain and moderate to severe pain are strongly associated with sleep difficulty in older adults. Further research is needed to better understand the burden and consequences of pain-related sleep problems in older adults.

The effects of Ginkgo biloba extract EGb 761 on mechanical and cold allodynia in a rat model of neuropathic pain.

BACKGROUND: Neuropathic pain is chronic pain that is caused by an injury to the peripheral or central nervous system. The symptoms of neuropathic pain are continuing pain, hyperalgesia, and allodynia. Ginkgo biloba extract is an oriental herbal medicine that has various pharmacological actions. We examined the effect of Ginkgo biloba extract, EGb 761, on the mechanical and cold allodynia in a rat model of neuropathic pain. METHODS: Male Sprague-Dawley rats were prepared by tightly ligating the left L5 and L6 spinal nerves. All the rats developed mechanical and cold allodynia 7 days after surgery. Fifty neuropathic rats were assigned into five groups for the intraperitoneal administration of drugs. The study was double-blind and the order of the treatments was randomized. Normal saline and EGb 761 (50, 100, 150, and 200 mg/kg) were administered, respectively, to the individual groups. We examined mechanical and cold allodynia at preadministration and at 15, 30, 60, 90, 120, 150, and 180 min after intraperitoneal drug administration. Mechanical allodynia was quantified by measuring the paw withdrawal threshold to stimuli with von Frey filaments of 1.0, 1.4, 2.0, 4.0, 6.0, 8.0, 10.0, 12.0, 15.0, and 26.0 g. Cold allodynia was quantified by measuring the frequency of foot lift with applying 100% acetone. We measured the locomotor function of the neuropathic rats by using the rotarod test to reveal if EGb 761 has side effects, such as sedation or reduced motor coordination. RESULTS: The control group showed no differences for mechanical and cold allodynia. For the EGb 761 groups, the paw withdrawal thresholds to mechanical stimuli and withdrawal frequencies to cold stimuli were significantly reduced versus the preadministration values and versus the control group. The duration of antiallodynic effects increased in a dose-dependent fashion, and these were maintained for 120 min at the highest dose (P < 0.05). Only at the highest dose (200 mg/kg) did EGb 761 reduce the rotarod performance time. CONCLUSION: We conclude that Ginkgo biloba extract, EGb 761, attenuates mechanical and cold allodynia in a rat model of neuropathic pain, and it may be useful for the management of neuropathic pain.

Intact Adelta-fibers up-regulate transient receptor potential A1 and contribute to cold hypersensitivity in neuropathic rats.

Mechanisms underlying cold hypersensitivity in neuropathic states are unclear. Recent data indicate both transient receptor potential (TRP) M8 and TRPA1 play a role. In relation to TRPA1, there are reported increases in mRNA. However, it is unknown whether TRPA1 mRNA is translated into functional receptors, whether these receptors are found on peripheral nociceptors and what population of primary afferents expresses the receptors. The present study provides several lines of evidence that TRPA1 receptors are expressed on intact primary sensory neurons and contribute to cold hypersensitivity following spinal nerve ligation (SNL). Immunohistochemical studies show that expression of TRPA1 is significantly increased in the ipsilateral compared with the contralateral L4 dorsal root ganglion (DRG). Using mustard oil (MO, selective TRPA1 agonist), Ca(2+) imaging demonstrates an increase in the percentage of MO-sensitive L4 DRG cells in SNL compared with sham and naive rats. The magnitude of the Ca(2+) response evoked by MO is also significantly larger in SNL compared with sham and naive rats. Behavioral studies demonstrate that SNL results in increased nocifensive behaviors to mechanical and cold stimulation that is not seen in sham or naive rats. Behavioral responses in sham rats are no different from naive rats. In vitro single fiber recordings demonstrate Adelta-fibers (intact L4 axons) in the nerve-injured hind paw have conduction velocities no different from naive rats. In contrast, compared with naive rats, mechanical thresholds of the Adelta-fibers in SNL rats are significantly decreased, the proportion of cold-sensitive and MO-sensitive Adelta-fibers is significantly increased and the response magnitude of Adelta-fibers to MO is significantly increased. MO-induced activity in Adelta-fibers is significantly reduced by Ruthenium Red (TRPA1 receptor antagonist). These results demonstrate that TRPA1 is expressed on peripheral nociceptors, and they are up-regulated on intact Adelta-fibers following nerve injury, contributing to cold hypersensitivity.

Quality of life, resource consumption and costs of spinal cord stimulation versus conventional medical management in neuropathic pain patients with failed back surgery syndrome (PROCESS trial).

BACKGROUND: Chronic back and leg pain conditions result in patients' loss of function, reduced quality of life and increased costs to the society. AIMS: To assess health-related quality of life (HRQoL) and cost implications of spinal cord stimulation plus non-surgical conventional medical management (SCS group) versus non-surgical conventional medical management alone (CMM group) in the management of neuropathic pain in patients with failed back surgery syndrome. METHODS: A total of 100 patients were randomised to either the SCS or CMM group. Healthcare resource consumption data relating to screening, the use of the implantable generator in SCS patients, hospital stay, and drug and non-drug pain-related treatment were collected prospectively. Resource consumption was costed using UK and Canadian 2005-2006 national figures. HRQoL was assessed using the EuroQol-5D (EQ-5D) questionnaire. Costs and outcomes were assessed for each patient over their first 6-months of the trial. RESULTS: The 6-month mean total healthcare cost in the SCS group (CAN$19,486; 12,653 euros) was significantly higher than in the CMM group (CAN$3994; 2594 euros), with a mean adjusted difference of CAN$15,395 (9997 euros) (p<0.001). However, the gain in HRQoL with SCS over the same period of time was markedly greater in the SCS group, with a mean EQ-5D score difference of 0.25 [p<0.001] and 0.21 [p<0.001], respectively at 3- and 6-months after adjusting for baseline variables. CONCLUSIONS: The addition of SCS to CMM in patients with neuropathic leg and back pain results in higher costs to health systems but also generates important improvements in patients' EQ-5D over the same period.

Movement imagery increases pain in people with neuropathic pain following complete thoracic spinal cord injury.

Spinal cord injury (SCI) results in deafferentation and the onset of neuropathic pain in a substantial proportion of people. Based on evidence suggesting motor cortex activation results in attenuation of neuropathic pain, we sought to determine whether neuropathic SCI pain could be modified by imagined movements of the foot. Fifteen subjects with a complete thoracic SCI (7 with below-level neuropathic pain and 8 without pain) were instructed in the use of movement imagery. Movement imagery was practiced three times daily for 7days. On the eighth day, subjects performed the movement imagery in the laboratory and recorded pain ratings during the period of imagined movement. Six out of 7 subjects with neuropathic pain reported an increase in pain during imagined movements from 2.9+/-0.7 during baseline to 5.0+/-1.0 during movement imagery (p<0.01). In SCI subjects without neuropathic pain, movement imagery evoked an increase in non-painful sensation intensity from a baseline of 1.9+/-0.7 to 4.8+/-1.3 during the movement imagery (p<0.01). Two subjects without a history of pain or non-painful phantom sensations had onset of dysesthesia while performing imagined movements. This study reports exacerbation of pain in response to imagined movements and it contrasts with reports of pain reduction in people with peripheral neuropathic pain. The potential mechanisms underlying this sensory enhancement with movement imagery are discussed.

IMF-Therapy (Intention controlled Myo-Feedback)--an innovative method in the treatment of peripheral nerve lesions.

Physiotherapy is a well established part of the rehabilitation of peripheral nerve paralysis. The aim of this type of treatment is to re-establish arbitrary functions by improving the patients' active and passive mobility as well as their strength and stamina. IMF-Therapy (Intention controlled Myo-Feedback) is an innovative method in the treatment of peripheral nerve lesions that goes beyond the purely neuro-scientific framework and also takes into account methods and concepts of the psychology of learning. The essential assumption is that things learnt in the past are firmly established in the long term motor memory and can be reactivated by the patient. From results achieved in 32 patients treated with this therapy it can be concluded that IMF-Therapy may be a promising additional rehabilitation tool in peripheral nerve lesion.

Cannabis in painful HIV-associated sensory neuropathy: a randomized placebo-controlled trial.

OBJECTIVE: To determine the effect of smoked cannabis on the neuropathic pain of HIV-associated sensory neuropathy and an experimental pain model. METHODS: Prospective randomized placebo-controlled trial conducted in the inpatient General Clinical Research Center between May 2003 and May 2005 involving adults with painful HIV-associated sensory neuropathy. Patients were randomly assigned to smoke either cannabis (3.56% tetrahydrocannabinol) or identical placebo cigarettes with the cannabinoids extracted three times daily for 5 days. Primary outcome measures included ratings of chronic pain and the percentage achieving >30% reduction in pain intensity. Acute analgesic and anti-hyperalgesic effects of smoked cannabis were assessed using a cutaneous heat stimulation procedure and the heat/capsaicin sensitization model. RESULTS: Fifty patients completed the entire trial. Smoked cannabis reduced daily pain by 34% (median reduction; IQR = -71, -16) vs 17% (IQR = -29, 8) with placebo (p = 0.03). Greater than 30% reduction in pain was reported by 52% in the cannabis group and by 24% in the placebo group (p = 0.04). The first cannabis cigarette reduced chronic pain by a median of 72% vs 15% with placebo (p < 0.001). Cannabis reduced experimentally induced hyperalgesia to both brush and von Frey hair stimuli (p < or = 0.05) but appeared to have little effect on the painfulness of noxious heat stimulation. No serious adverse events were reported. CONCLUSION: Smoked cannabis was well tolerated and effectively relieved chronic neuropathic pain from HIV-associated sensory neuropathy. The findings are comparable to oral drugs used for chronic neuropathic pain.

Spinal cord stimulation: a seven-year audit.

OBJECTIVE: To evaluate the outcome and complications of spinal cord stimulation (SCS) for chronic neuropathic pain in an Australian population. MATERIALS AND METHODS: An independent researcher retrospectively examined the records of 138 patients trialing SCS between 1995 and 2002 at our institution. Information collected included pain relief, ability to perform activities of daily living (ADLs), return to work and reduction in opiate analgesia. Clinical, psychological, demographic and financial data were also collected. RESULTS: Of 138 patients who trialed SCS, 103 (74.7%) achieved a greater than 50% reduction in their pain and proceeded to permanent implantation. At 1 year following permanent implantation, 84.4% of these still had a reduction in their pain by greater than 50%. The majority of patients, 59.1%, stated that their analgesia was good (50-74% pain reduction). All patients required opiate analgesics prior to SCS implantation, but this fell to 54.6% after SCS implantation. Additionally, 73.6% had a significant improvement in their ability to perform ADLs and 24% of patients were able to return to work. CONCLUSION: SCS is an effective treatment in the control of chronic neuropathic pain, particularly in combination with comprehensive medical management within a multidisciplinary pain management centre.