A number of different diseases or injuries can damage the central or peripheral nervous system and produce neuropathic pain (NP), which seems to be more difficult to treat than many other types of ...chronic pain. As a group, patients with NP have greater medical co-morbidity burden than age- and sex-adjusted controls, which makes determining the humanistic and economic burden attributable to NP challenging.
Health-related quality of life (HR-QOL) is substantially impaired among patients with NP. Patients describe pain-related interference in multiple HR-QOL and functional domains, as well as reduced ability to work and reduced mobility due to their pain. In addition, the spouses of NP patients have been shown to experience adverse social consequences related to NP. In randomized controlled trials, several medications have been shown to improve various measures of HR-QOL. Changes in HR-QOL appear to be tightly linked to pain relief, but not to the development of adverse effects. However, in cross-sectional studies, many patients continue to have moderate or severe pain and markedly impaired HR-QOL, despite taking medications prescribed for NP. The quality of NP treatment appears to be poor, with few patients receiving recommended medications in efficacious dosages.
The substantial costs to society of NP derive from direct medical costs, loss of the ability to work, loss of caregivers’ ability to work and possibly greater need for institutionalization or other living assistance. No single study has measured all of these costs to society for chronic NP. The cost effectiveness of various interventions for the treatment or prevention of different types of NP has been assessed in several different studies. The most-studied diseases are post-herpetic neuralgia and painful diabetic neuropathy, for which tricyclic antidepressants (both amitriptyline and desipramine) have been found to be either cost effective or dominant relative to other strategies.
Increasing the use of cost-effective therapies such as tricyclic antidepressants for post-herpetic neuralgia and painful diabetic neuropathy may improve the HR-QOL of patients and decrease societal costs. Head-to-head clinical trials comparing NP therapies are needed to help assess the relative clinical efficacy of treatments, ideally using HR-QOL and utility outcomes. The full costs to society of NP, including productivity loss costs, have not been determined for chronic NP. Improved relative efficacy, utility and cost estimates would facilitate future cost-effectiveness research in NP.
Abstract A number of different treatments for neuropathic pain have been studied, but the literature is sizable, rapidly evolving, and lacks important information about practical aspects of patient ...management. Under the auspices of the International Association for the Study of Pain (IASP) Neuropathic Pain Special Interest Group (NeuPSIG), a consensus process was used to develop evidence-based guidelines for the pharmacologic management of neuropathic pain that take into account clinical efficacy, adverse effects, impact on health-related quality of life, convenience, and costs. On the basis of randomized clinical trials, medications recommended as first-line treatments for neuropathic pain included certain antidepressants (i.e., tricyclic antidepressants and dual reuptake inhibitors of both serotonin and norepinephrine), calcium channel α2 -δ ligands (i.e., gabapentin and pregabalin), and topical lidocaine. Opioid analgesics and tramadol were recommended as second-line treatments that can be considered for first-line use in selected clinical circumstances. Other medications that generally would be used as third-line treatments include certain other antidepressant and antiepileptic medications, topical capsaicin, mexiletine, and N -methyl- d -aspartate receptor antagonists. Two other national and international associations recently published pharmacologic treatment guidelines for neuropathic pain, which are summarized and contrasted with the NeuPSIG recommendations. Recent guidelines for the use of neurostimulation for the treatment of neuropathic pain also are summarized. For all treatments for neuropathic pain, long-term studies, head-to-head comparisons, and studies of treatment combinations are a priority for future research.
Neuropathic pain (NP) is often refractory to pharmacologic and noninterventional treatment. On behalf of the International Association for the Study of Pain Neuropathic Pain Special Interest Group, ...the authors evaluated systematic reviews, clinical trials, and existing guidelines for the interventional management of NP. Evidence is summarized and presented for neural blockade, spinal cord stimulation (SCS), intrathecal medication, and neurosurgical interventions in patients with the following peripheral and central NP conditions: herpes zoster and postherpetic neuralgia (PHN); painful diabetic and other peripheral neuropathies; spinal cord injury NP; central poststroke pain; radiculopathy and failed back surgery syndrome (FBSS); complex regional pain syndrome (CRPS); and trigeminal neuralgia and neuropathy. Due to the paucity of high-quality clinical trials, no strong recommendations can be made. Four weak recommendations based on the amount and consistency of evidence, including degree of efficacy and safety, are: 1) epidural injections for herpes zoster; 2) steroid injections for radiculopathy; 3) SCS for FBSS; and 4) SCS for CRPS type 1. Based on the available data, we recommend not to use sympathetic blocks for PHN nor radiofrequency lesions for radiculopathy. No other conclusive recommendations can be made due to the poor quality of available data. Whenever possible, these interventions should either be part of randomized clinical trials or documented in pain registries. Priorities for future research include randomized clinical trials, long-term studies, and head-to-head comparisons among different interventional and noninterventional treatments.
Patients with neuropathic pain (NP) are challenging to manage and evidence-based clinical recommendations for pharmacologic management are needed. Systematic literature reviews, randomized clinical ...trials, and existing guidelines were evaluated at a consensus meeting. Medications were considered for recommendation if their efficacy was supported by at least one methodologically-sound, randomized clinical trial (RCT) demonstrating superiority to placebo or a relevant comparison treatment. Recommendations were based on the amount and consistency of evidence, degree of efficacy, safety, and clinical experience of the authors. Available RCTs typically evaluated chronic NP of moderate to severe intensity. Recommended first-line treatments include certain antidepressants (i.e., tricyclic antidepressants and dual reuptake inhibitors of both serotonin and norepinephrine), calcium channel alpha2-delta ligands (i.e., gabapentin and pregabalin), and topical lidocaine. Opioid analgesics and tramadol are recommended as generally second-line treatments that can be considered for first-line use in select clinical circumstances. Other medications that would generally be used as third-line treatments but that could also be used as second-line treatments in some circumstances include certain antiepileptic and antidepressant medications, mexiletine, N-methyl-D-aspartate receptor antagonists, and topical capsaicin. Medication selection should be individualized, considering side effects, potential beneficial or deleterious effects on comorbidities, and whether prompt onset of pain relief is necessary. To date, no medications have demonstrated efficacy in lumbosacral radiculopathy, which is probably the most common type of NP. Long-term studies, head-to-head comparisons between medications, studies involving combinations of medications, and RCTs examining treatment of central NP are lacking and should be a priority for future research.
Pain is common in patients with multiple sclerosis (MS), but estimates of its prevalence have varied widely. The literature describing pain in MS patients spans four decades and has employed a range ...of different methodologies. We undertook a systematic review in order to summarize current understanding of the association between MS and pain and provide a basis for the design and interpretation of future studies. The point prevalence of pain in patients with MS is nearly 50%, and approximately 75% of patients report having had pain within one month of assessment. Pain adversely affects most aspects of health-related quality of life, including functional domains such as the ability to work. The presence of pain in patients with MS is associated with increased age, duration of illness, depression, degree of functional impairment, and fatigue. Several different types of pain are found in patients with MS, including extremity pain, trigeminal neuralgia, Lhermitte's sign, painful tonic spasms, back pain, and headache. Putative mechanisms of pain in patients with MS are discussed, and a classification of pain in MS is proposed. Few randomized clinical trials of treatments for MS pain have been conducted, and the limitations of current knowledge regarding approaches for treating MS pain are discussed. Suggestions for future studies that would increase understanding of the natural history, mechanisms, and treatment of pain in patients with MS are presented.
Background:
Painful diabetic neuropathy is common and adversely affects patients’ quality of life and function. Several treatment options exist, but their relative efficacy and value are unknown.
...Objective:
To determine the relative efficacy, costs and cost effectiveness of the first-line treatment options for painful diabetic neuropathy.
Methods:
Published and unpublished clinical trial and cross-sectional data were incorporated into a decision analytic model to estimate the net health and cost consequences of treatment for painful diabetic peripheral neuropathy over 3-month (base case), 1-month and 6-month timeframes. Efficacy was measured in QALYs, and costs were measured in $US, year 2006 values, using a US thirdparty payer perspective.
The patients included in the model were outpatients with moderate to severe pain associated with diabetic peripheral neuropathy and no contraindications to treatment with tricyclic antidepressants. Four medications were compared: desipramine 100 mg/day, gabapentin 2400 mg/day, pregabalin 300 mg/day and duloxetine 60 mg/day.
Results:
Desipramine and duloxetine were both more effective and less expensive than gabapentin and pregabalin in the base-case analysis and through a wide range of sensitivity analyses. Duloxetine offered borderline value compared with desipramine in the base case ($US47 700 per QALY), but not when incorporating baseline-observation-carried-forward analyses of the clinical trial data ($US867 000 per QALY). The results were also sensitive to the probability of obtaining pain relief with duloxetine.
Conclusions:
Desipramine (100 mg/day) and duloxetine (60 mg/day) appear to be more cost effective than gabapentin or pregabalin for treating painful diabetic neuropathy. The estimated value of duloxetine relative to desipramine depends on the assumptions made in the statistical analyses of clinical trial data.
OBJECTIVES: To determine the healthcare costs of acute and chronic pain associated with herpes zoster.
DESIGN: Retrospective cohort analysis.
SETTING: Inpatient and outpatient care.
PARTICIPANTS: ...Patients were selected from Medicare, commercial insurance, and Medicaid claims databases if they had a diagnosis of herpes zoster or postherpetic neuralgia (PHN) or were prescribed analgesics after a diagnosis of herpes zoster (possible PHN) and were matched to controls for demographic and clinical factors using propensity scores.
MEASUREMENTS: One‐year excess healthcare expenditures attributable to herpes zoster pain or PHN were calculated for inpatient, outpatient, and prescription drug services.
RESULTS: For the Medicare cohort, the average excess cost per patient was $1,300 in the year after a diagnosis of herpes zoster with 30 days or fewer of analgesic use and ranged from $2,200 to $2,300 per patient with PHN or possible PHN. Patients with possible PHN were 53% more prevalent than patients with PHN in the Medicare cohort and accounted for half of all excess expenditures. Findings were similar in the younger cohorts with commercial insurance and Medicaid except that costs attributable to PHN and possible PHN were higher, and patients with possible PHN were three to five times as prevalent as patients with PHN.
CONCLUSION: Healthcare costs associated with PHN were substantially greater than those associated with herpes zoster pain that resolved within 30 days. The data suggest that as many as 80% of patients with PHN may not be diagnosed with PHN and that these patients account for at least half of PHN expenditures.
Objectives: Pain management continues to be suboptimal in emergency departments (EDs). Several studies have documented failures in the processes of care, such as whether opioid analgesics were ...given. The objectives of this study were to measure the outcomes following administration of intravenous (IV) opioids and to identify clinical factors that may predict poor analgesic outcomes in these patients.
Methods: In this prospective cohort study, emergency patients were enrolled if they were prescribed IV morphine or hydromorphone (the most commonly used IV opioids in the study hospital) as their initial analgesic. Patients were surveyed at the time of opioid administration and 1 to 2 hours after the initial opioid dosage. They scored their pain using a verbal 0–10 pain scale. The following binary analgesic variables were primarily used to identify patients with poor analgesic outcomes: 1) a pain score reduction of less than 50%, 2) a postanalgesic pain score of 7 or greater (using the 0–10 numeric rating scale), and 3) the development of opioid‐related side effects. Logistic regression analyses were used to study the effects of demographic, clinical, and treatment covariates on the outcome variables.
Results: A total of 2,414 were approached for enrollment, of whom 1,312 were ineligible (658 were identified more than 2 hours after IV opioid was administered and 341 received another analgesic before or with the IV opioid) and 369 declined to consent. A total of 691 patients with a median baseline pain score of 9 were included in the final analyses. Following treatment, 57% of the cohort failed to achieve a 50% pain score reduction, 36% had a pain score of 7 or greater, 48% wanted additional analgesics, and 23% developed opioid‐related side effects. In the logistic regression analyses, the factors associated with poor analgesia (both <50% pain score reduction and postanalgesic pain score of ≥7) were the use of long‐acting opioids at home, administration of additional analgesics, provider concern for drug‐seeking behavior, and older age. An initial pain score of 10 was also strongly associated with a postanalgesic pain score of ≥7. African American patients who were not taking opioids at home were less likely to achieve a 50% pain score reduction than other patients, despite receiving similar initial and total equianalgesic dosages. None of the variables we assessed were significantly associated with the development of opioid‐related side effects.
Conclusions: Poor analgesic outcomes were common in this cohort of ED patients prescribed IV opioids. Patients taking long‐acting opioids, those thought to be drug‐seeking, older patients, those with an initial pain score of 10, and possibly African American patients are at especially high risk of poor analgesia following IV opioid administration.
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