Clinical characteristics and patterns of healthcare utilization in patients with painful neuropathic disorders in UK general practice: a retrospective cohort study.

BACKGROUND: Clinical characteristics and patterns of healthcare utilization in patients with painful neuropathic disorders (PNDs) who are under the care of general practitioners (GPs) in the UK are not well understood. METHODS: Using a large electronic UK database, we identified all adults (age ≥ 18 years) with any GP encounters between 1 January 2006-31 December 2006 at which a diagnosis of PND was noted ("PND patients"). An age-and gender-matched comparison group also was constituted consisting of randomly selected patients with one or more GP encounters-but no mention of PNDs-during this period. Characteristics and patterns of healthcare utilization of patients in the two groups were then examined over the one-year study period. RESULTS: The study sample consisted of 31,688 patients with mention of PNDs and an equal number of matched comparators; mean age was 56 years, and 62% were women. The prevalence of various comorbidities was higher among patients in the PND group, including digestive disorders (31% vs. 17% for comparison group), circulatory disorders (29% vs. 22%), and depression (4% vs. 3%) (all p < 0.01). Receipt of prescriptions for pain-related pharmacotherapy also was higher among PND patients, including nonsteroidal anti-inflammatory drugs (56% of PND patients had one or more such prescriptions vs. only 22% in the comparison group), opioids (49% vs. 12%), tricyclic antidepressants (20% vs. 1%), and antiepileptics (12% vs. 1%) (all p < 0.01). PND patients also averaged significantly more GP visits (22.8 vs. 14.2) and referrals to specialists (2.8 vs. 1.4) over one year (both comparisons p < 0.01). CONCLUSIONS: Patients with PNDs under the care of GPs in the UK have relatively high levels of use of healthcare services and pain-related pharmacotherapy.

Reliability of a 1-week recall period for the Medical Outcomes Study Sleep Scale (MOS-SS) in patients with fibromyalgia.

OBJECTIVE: To evaluate the reliability of a one-week versus a four-week recall period of the Medical Outcomes Study Sleep Scale (MOS-SS) in patients with fibromyalgia (FM). METHODS: The MOS-SS was administered by mail to patients with a confirmed diagnosis of FM and a current pain rating of > 2 (0-10 point numerical rating scale) recruited through newspapers, support groups, and the Internet. Reliability of MOS-SS subscale domains was evaluated using test-retest methodology separated by a 1-3 day interval for the 4-week recall period and a 7-day interval for the 1-week recall period. Patient Impression of Change was evaluated for sleep, and for patients with no change, the intraclass correlation coefficient (ICC) and the Pearson correlation coefficient was calculated for MOS-SS subscales. RESULTS: Of 129 patients enrolled, 91.3% were female, mean age was 49.4 +/- 11.0 years; self-rated FM severity was moderate-to-severe in 88.1% of patients. MOS-SS subscale scores were similar for both recall periods with little variation between test-retest. The 9-item Sleep Problems Index scores ranged from 57.2 +/- 14.5 to 61.9 +/- 15.8 across all assessments and demonstrated high reliability which was similar for the 1-week (ICC 0.81) and 4-week (ICC 0.89) recall periods. For the other MOS-SS subscales, the 1-week recall period also showed good reliability, which was consistent for the ICC and Pearson correlation coefficients. CONCLUSION: A 1-week recall period is adequately reliable for use of the MOS-SS in studies evaluating sleep disturbance in patients with FM.

Magnitude of potentially inappropriate prescribing in Germany among older patients with generalized anxiety disorder.

BACKGROUND: Several medications commonly used to treat generalized anxiety disorder (GAD) have been designated "potentially inappropriate" for use in patients aged > or =65 years because their risks may outweigh their potential benefits. The actual extent of use of these agents in clinical practice is unknown, however. METHODS: Using a database with information from encounters with general practitioners (GP) in Germany, we identified all patients, aged > or =65 years, with any GP office visits or dispensed prescriptions with a diagnosis of GAD (ICD-10 diagnosis code F41.1) between 10/1/2003 and 9/30/2004 ("GAD patients"). Among GAD-related medications (including benzodiazepines, tricyclic antidepressants [TCAs], selective serotonin reuptake inhibitors, venlafaxine, hydroxyzine, buspirone, pregabalin, and trifluoperazine), long-acting benzodiazepines, selected short-acting benzodiazepines at relatively high dosages, selected TCAs, and hydroxyzine were designated "potentially inappropriate" for use in patients aged > or = 65 years, based on published criteria. RESULTS: A total of 975 elderly patients with GAD were identified. Mean age was 75 years, and 72% were women; 29% had diagnoses of comorbid depression. Forty percent of study subjects received potentially inappropriate agents - most commonly, bromazepam (10% of all subjects), diazepam (9%), doxepin (7%), amitriptyline (5%), and lorazepam (5%). Twenty-three percent of study subjects received long-acting benzodiazepines, 10% received short-acting benzodiazepines at relatively high doses, and 12% received TCAs designated as potentially inappropriate. CONCLUSION: GPs in Germany often prescribe medications that have been designated as potentially inappropriate to their elderly patients with GAD - especially those with comorbid depressive disorders. Further research is needed to ascertain whether there are specific subgoups of elderly patients with GAD for whom the benefits of these medications outweigh their risks.

Use of pregabalin in patients with painful neuropathic disorders under the care of general practitioners in the U.K.

PURPOSE: To examine the use of pregabalin in patients with painful neuropathic disorders under the care of general practitioners (GPs) in the U.K. MATERIALS AND METHODS: Using a large U.K. database of GP encounters, we identified all persons aged > or = 18 years with at least one GP encounter with a diagnosis of a painful neuropathic disorder (eg, postherpetic neuralgia, diabetic peripheral neuropathy) between January 1, 2004 and July 31, 2006. Among these patients, we then identified those who initiated therapy with pregabalin; the date of initial receipt of pregabalin was designated the "index date." We then examined use of pregabalin over the 6-month period following this date ("follow-up"), as well as changes in the use of other pain-related medications (eg, opioids, tricyclic antidepressants [TCAs], other antiepileptics [AEDs]) between the 6-month period preceding the index date ("pretreatment") and follow-up. Patients with less than 6 months of pretreatment and follow-up data were excluded, as were those without any encounters during pretreatment for a painful neuropathic disorder. RESULTS: A total of 1,400 patients (1.4% of all identified patients with painful neuropathic disorders) initiated therapy with pregabalin and met all other entry criteria; mean age was 62 years, and 58% were women. During pretreatment, most (54%) patients received three or more different types of pain-related medications. During follow-up, patients averaged four prescriptions for pregabalin, totaling 93 therapy days. Compared with pretreatment, fewer patients received other pain-related medications during follow-up, including TCAs (37% during pretreatment vs. 27% during follow-up), opioids (64% vs. 55%), and AEDs other than pregabalin (36% vs. 16%) (all P < 0.01). CONCLUSIONS: In the U.K., many patients prescribed pregabalin by their GPs may have been refractory to other pain-related medications. Use of these medications declined following initiation of pregabalin therapy.

Clinical and economic characteristics of patients with painful neuropathic disorders in Germany.

Using a large database with information from general practitioners (GP) throughout Germany, we identified all adults (age > or = 18 years) with encounters for painful neuropathic disorders (PNDs) between August 1, 2005 and July 31, 2006 (PND patients). We also constituted an age- and sex-matched comparison group, consisting of randomly selected patients without any GP encounters for PNDs during the same period. Selected characteristics were then compared between PND patients and those in the comparison group over the 1-year study period. The study sample consisted of 275,685 PND patients and a similar number in the matched comparison group; mean age was 53.7 years, and 57% were women. PND patients were more likely than matched comparators to have encounters for various comorbidities, including circulatory system disorders (47% vs. 20%, respectively), depression (9% vs. 2%), and anxiety (4% vs. 1%) (all P < 0.01). They also were more likely to have received pain-related medications (57% vs. 13% for comparison group; P < 0.01)--most commonly, nonsteroidal anti-inflammatory drugs, benzodiazepines, and opioids, and less often, tricyclic antidepressants and anti-epileptics. PND patients averaged 7.3 more GP visits during the year (mean [95% CI] = 9.9 [9.9, 9.9] vs. 2.6 [2.6, 2.7] for comparison group); they also had significantly more specialist referrals and physician-excused absences from work (all P < 0.01). Patients with PNDs under the care of GPs in Germany have comparatively more comorbidities and higher levels of use of healthcare services. The pain-related medications that these patients receive raise concerns that PNDs may not be optimally treated in these settings.

Conceptual adequacy of the neuropathic pain symptom inventory in six countries.

BACKGROUND: Neuropathic pain results from a nerve lesion or nerve damage. Because it is a subjective experience, patient-reported outcomes may measure both the symptoms and impact on the patient's life. The purpose of this study was to determine whether the Neuropathic Pain Symptom Inventory (NPSI) adequately assesses neuropathic pain symptoms in patients with diabetic peripheral neuropathy, post-herpetic neuralgia, trigeminal neuralgia, and sciatica across multiple cultures. METHODS: From data collected from 132 subjects in 6 countries, qualitative research methods identified their most important symptoms (and verbal descriptions) associated with neuropathic pain. A core set of commonly described symptoms spanning multiple cultures was also described. Moderators using a semi-structured discussion guide conducted focus groups consisting of patients in the U.S., Brazil, Japan, China, Finland, and Spain to elicit concepts that were most important and relevant (concept elicitation phase). Study subjects ranked the importance of each neuropathic pain symptom, completed the NPSI, and commented on its ability to capture key symptoms (face and content validation phase). RESULTS: Descriptive terms for sensations of neuropathic pain were similar in all countries; burning, electric shocks, and pins and needles were among the most-common sensations. Individuals with neuropathic pain experienced all sensations that were included in the NPSI. They also tended to describe pins and needles and numbness interchangeably, perhaps reflecting the relative number of DPN subjects on study. CONCLUSION: Based on data from these focus groups, the NPSI is an acceptable instrument for assessing neuropathic pain.

Relationship of American Spinal Injury Association Impairment Scale Grade to Post-injury Hospitalization and Costs in Thoracic Spinal Cord Injury.

BACKGROUND: The lifetime economic burden of thoracic spinal cord injury (SCI) is known to be high, but evidence of variability of costs in relation to the American Spinal Injury Association Impairment Scale (AIS) grade is limited. OBJECTIVE: To estimate lifetime economic costs of hospitalization by AIS grade in thoracic SCI. METHODS: Using SCI Model Systems data from January 2000 to March 2016 from the National Spinal Cord Injury Statistical Center, we estimated mean total annual days of all-cause hospitalization by AIS grade among persons with thoracic SCI, based on assessments 1, 5, and 10 yr post-injury. We combined this information with secondary cost data and projections of life expectancy to estimate lifetime economic costs of hospitalization by AIS grade in persons aged 35 yr at time of thoracic SCI. Future costs were discounted to present value at 3% annually. RESULTS: One year post-injury, mean total annual days of hospitalization ranged from 2.1 for persons with AIS-D injuries to 5.9 for those who were AIS-A. Similar differences were noted 5 and 10 yr post-SCI. The estimated net present value of expected lifetime costs of hospitalization following thoracic SCI at age 35 yr was $321 534, $249 514, $188 989, and $68 120 (2015 US$) for AIS-A, AIS-B, AIS-C, and AIS-D injuries, respectively. CONCLUSION: Persons with less severe thoracic SCI, as reflected in AIS grade, spend fewer days in hospital over their lifetimes, leading to lower costs of inpatient care. Therapies improving AIS grade following thoracic SCI may provide cost savings in addition to addressing substantial unmet need.

Clinical characteristics and pain management among patients with painful peripheral neuropathic disorders in general practice settings.

Alleviating chronic pain is a global healthcare priority. Understanding the medical profile and current treatment patterns in patients with painful neuropathic disorders (PNDs) is crucial to the development of effective pain management strategies. Thus, our objective was to describe the demographic and clinical characteristics of persons with PNDs and their use of pain medications. Using the general practice research database, we categorized PNDs in two ways: Pure PNDs (which include diabetic neuropathy, postherpetic neuralgia, etc.; N=16,690) and Mixed PNDs (which include back/neck pain with neuropathic involvement; N=14,309). On average, PND patients were 55 years old (Pure, 55.4 [SD=16.9] years; Mixed, 54.3 [SD=16.4] years). Over a third had other chronic pain-related (Pure, 37.5%; Mixed, 37.1%) and nearly a quarter had non-pain related (Pure, 28.1%; Mixed, 24.1%) comorbidities. Use of medications with clinically demonstrated efficacy in PNDs was higher among patients with Pure PNDs (tricyclic antidepressants [Pure, 16.6%; Mixed, 10.1%]; 2nd generation antidepressants [Pure, 11.0%; Mixed, 9.7%]; and antiepileptics [Pure, 12.2%; Mixed, 2.6%]), whereas use of NSAIDs (Pure, 43.1%; Mixed, 65.2%) and opioids (Pure, 8.5%; Mixed, 14.3%) was higher among patients with Mixed PNDs. Average daily doses of select neuropathic pain-related medications among PND patients (Pure and Mixed) were lower than those recommended for neuropathic pain. Among both Pure and Mixed PND patients, use and doses of evidenced-based neuropathic pain-related medications was low, and lower than the use of NSAIDs (a medication class with no proven efficacy for PNDs) in each group, suggesting possible sub-optimal neuropathic pain management among these patients.

Use of tricyclic antidepressants in older patients with diabetic peripheral neuropathy.

PURPOSE: To describe patterns of use of tricyclic antidepressants (TCAs) (eg, amitriptyline, nortriptyline) among older patients with diabetic peripheral neuropathy (DPN). MATERIALS AND METHODS: Using a large, integrated, US health-insurance claims database, we identified all patients who received TCAs between January 1, 1999 and June 30, 2001 ("study period"). Among these persons, we then selected those who: (1) were aged >or=65 years as of the date of first receipt of a TCA during the study period; and (2) had one or more healthcare encounters with a diagnosis of DPN in the 30-day period immediately preceding date of first receipt of a TCA. We then examined the prevalence of selected comorbidities and concurrent use of medications which might render inappropriate the prescribing of TCAs, based on a listing of contraindications, warnings, and precautions found in the package inserts for these medications. Patterns of TCA prescribing were examined, based on information on paid claims. RESULTS: There were 349 DPN patients, aged >or=65 years, who received TCAs. Mean age was 73.8 years, 55.9% were women, and 17.9% had diagnoses of depression. Most patients (84.0%) began therapy with amitriptyline. Almost one-half of study patients had indicators of potentially inappropriate TCA use, primarily cardiovascular comorbidities. Mean TCA dose among patients with and without these indicators was 23.3 (+/-13.4) mg and 25.4 (+/-15.3) mg, respectively (P=0.42). CONCLUSIONS: The high prevalence of contraindications, warnings, or precautions and the low level of TCA exposure suggest that many older patients with DPN who receive TCAs may be inappropriately treated.

Cost-effectiveness of pregabalin for the management of neuropathic pain associated with diabetic peripheral neuropathy and postherpetic neuralgia: a Canadian perspective.

BACKGROUND: Neuropathic pain (NeP) is a chronic condition that occurs frequently with diabetes and herpes zoster infection. In addition to potentially lasting many years, the relationship between chronic pain, anxiety/depression, and sleep, also referred to as the triad of pain, causes functional impairment in many areas of life. OBJECTIVE: The aim of this study was to examine the 12-week cost-effectiveness of 2 treatments of NeP, pregabalin versus gabapentin, in managing diabetic peripheral neuropathy (DPN) and postherpetic neuralgia (PHN) in a Canadian setting. METHODS: A stochastic simulation model evaluating NeP treatment was adapted to the Canadian setting. Using data from clinical trials of pregabalin (150-600 mg/d) and gabapentin (900-3600 mg/d), the model simulated 12-week treatment outcomes for patients with DPN or PHN. Resource utilization was identified through an Internet-based survey among 80 Canadian physicians. Utility values (as measured using the EuroQol EQ-5D) were obtained from 126 NeP patients participating in a cross-sectional study conducted at Canadian primary care sites. The economic analysis was expressed as incremental cost per quality-adjusted life year (QALY) gained and as incremental cost per day with no or mild pain. Model sensitivity to changes in key parameters was assessed. RESULTS: Following 12-week treatment, compared with gabapentin, pregabalin was projected to result in 6 and 9 additional days with no or mild pain for patients with DPN and PHN, respectively. Pregabalin therapy was estimated to provide an additional 0.0047 QALY and 0.0086 QALY over gabapentin administration, for DPN and PHN, respectively. Mean (SE) direct costs per DPN patient were estimated as 837.53 Can dollars (37.31 dollars) (2004 dollars) with gabapentin and 818.49 dollars (36.50 dollars) with pregabalin, and per PHN patient as 720.61 dollars (33.70 dollars) with gabapentin and 667.07 dollars (25.33 dollars) with pregabalin. Model findings were sensitive to variation in the dose and corresponding cost of the comparator, but not in other parameters. CONCLUSION: Based on the results of this analysis, in the treatment of NeP associated with DPN or PHN, pregabalin was a dominant or cost-effective treatment strategy compared with gabapentin.

Treatment of peripheral neuropathic pain: a simulation model.

OBJECTIVE: To describe the use of a generalizable stochastic-simulation model of the treatment of neuropathic pain associated with peripheral neuropathies. METHODS: We developed a model to simulate treatment outcomes in a hypothetical cohort of patients with peripheral neuropathies. Each patient was randomly assigned an average pretreatment daily pain score (on a 0-10 scale), based on an assumed distribution of mean pretreatment pain scores in the cohort. Patients were randomly assigned daily pain scores, based on their pretreatment average and an assumed distribution of daily pain scores around this mean. Treatment outcomes were then simulated using the expected mean change (vs. baseline) in pain scores. Model outcomes include the expected increase in days with no or mild pain (score < or = 3), days with > or = 30% and > or = 50% reductions in pain intensity, and days with 2- and 3-point absolute reductions in pain intensity. To illustrate its use, the model was estimated over a 12-week period using data from a recent clinical trial of a new antiepileptic (pregabalin). RESULTS: Treatment over 12 weeks (84 days) was projected to result in 26 (+/-0.4) (mean [+/-SE]) additional (vs. no treatment) days with no or mild pain, 33 (+/-0.5) days with a > or = 30% reduction in pain intensity, 28 (+/-0.4) days with > or = 50% reduction in pain intensity, and 34 (+/-0.5) and 30 (+/-0.5) days with > or = 2-point and > or = 3-point absolute reductions in pain intensity. CONCLUSIONS: When combined with data on health-state utilities and treatment costs, this new analytical tool can provide a foundation for formal cost-effectiveness evaluations of interventions for painful peripheral neuropathies.

The burden of neuropathic pain: results from a cross-sectional survey.

BACKGROUND: There are few published data on the treatment patterns and burden of neuropathic pain. We have investigated this in a large, observational, cross-sectional survey. METHODS: We surveyed 602 patients with neuropathic pain recruited from general practitioners in six European countries. Physicians recorded demographic and treatment information, including prescription medications. Patients completed Brief Pain Inventory (BPI) severity and interference questions, the EuroQol (EQ-5D), and questions about their productivity, non-prescription treatments, and frequency of physician visits. The BPI Pain Severity score (range: 0-10) is the mean of worst, least, average, and current pain ratings, with scores of 4-6 and 7-10 considered moderate and severe, respectively. We evaluated the impact of pain severity on functioning using analysis of variance models and chi2 tests. RESULTS: Mean (SD) age was 62.9 (14.4) years (50% female). Most patients reported moderate (54%) or severe (25%) pain. Nearly all patients (93%) were prescribed medications for their neuropathic pain: analgesics (71%); anti-epileptics (51%); antidepressants (29%); sedatives/hypnotics (15%). Seventy-six percent visited their physician at least once in the past month. Employment status was affected in 43% of patients; those employed missed a mean (SD) of 5.5 (9.8) workdays during the past month. Pain severity was associated significantly (P<0.001) with poorer EQ-5D scores (mild=0.67, moderate=0.46, severe=0.16), greater disruption of employment status (mild=24%, moderate=48%, severe=54%), and more frequent physician visits (% with one or more visits: mild=66%, moderate=79%, severe=83%). CONCLUSIONS: Patients with neuropathic pain visit their physician frequently and report substantial pain that interferes with daily functioning despite receiving treatment.

Patient burden of trigeminal neuralgia: results from a cross-sectional survey of health state impairment and treatment patterns in six European countries.

Trigeminal neuralgia (TN) is an uncommon neuropathic condition associated with excruciating facial pain. It is important to determine the effect of TN pain on patient functioning and to characterize relevant pharmacologic treatment patterns and health resource utilization in general practice. Eighty-two patients with TN were identified in a general practice setting during an observational survey of broad neuropathic pain syndromes in six European countries. Patients answered a questionnaire that included pain severity and interference items from the modified Short Form Brief Pain Inventory (mBPI-SF), the EuroQol Survey of functioning and well-being (EQ-5D), and questions related to current treatment, health status, and resource utilization. Physicians provided information on medications prescribed for TN pain and pain-related comorbidities (anxiety, depression, and sleep disturbance). The mean patient age was 62.7 +/- 15.8 years, 46% were > or =65 years, and 66% of patients had TN >1 year of duration. The mean Pain Severity Index was 4.2 (range 0-10), reflecting moderate pain despite 94% of patients taking prescription medications for their TN pain. Prescription medications included carbamazepine (mean daily dose 534.1 +/- 269.8 mg), the recommended first-line pharmacologic therapy for TN. Pain severity was significantly associated with reduced EQ-5D health state valuation (P < 0.001) and greater pain interference (mBPI-SF) (P < 0.001). These findings demonstrate that TN pain presents a substantial patient burden expressed as interference with daily functioning and reduced health status associated with pain severity. This burden may result from both suboptimal management strategies and the frequent resistance of this neuropathic condition to treatment, and suggests a need for more effective pain management strategies.

Prevalence of contraindicated medical conditions and use of precluded medications in patients with painful neuropathic disorders prescribed amitriptyline.

Amitriptyline is a tricyclic antidepressant that is historically indicated and used to manage depression. More recently, due to clinical evidence demonstrating efficacy, it is often prescribed in the management of painful neuropathic disorders (PNDs). However, the amitriptyline label contains numerous preclusions (contraindications, warnings/precautions, drug interactions). Our objective was to measure the frequency of amitriptyline prescriptions in PND patients using the U.K. General Practice Research Database and assess whether any prescriptions were given to patients with preclusions listed in the product label. We identified a total of 13,546 patients (mean age 59 +/- 16.2 years; 66.7% female) who had a diagnosis of a PND and received > or =1 prescription for amitriptyline between July 1998 and June 2001. Nearly half (46.7%) of PND patients prescribed amitriptyline had > or =1 preclusion for its use; 3.5% had > or =1 contraindication; 22% had > or =1 warning/precaution; and 33% received > or =1 medication with a potential for drug interactions with amitriptyline. Preclusions were more likely in women than in men (48.3% vs. 43.4%, P < 0.0001); their incidence increased with age (42.8%, 50.4%, 55.1%, and 52.3% among those ages <65, 65-74, 75-84, and 85+ years, P < 0.0001), and the number of patients with preclusions was the highest in the phantom limb pain group (67.4%) and lowest in the atypical facial pain group (42.9%), P < 0.001. The average daily amitriptyline doses (starting: 33.6 +/- 32.4 mg; maintenance: 42.1 +/- 39.9 mg) were low compared to those used for the treatment of depression. Results indicate that, in a significant number of cases, the existence of preclusions did not prevent the prescribing of amitriptyline. Our findings raise a potential concern about the way this medication is being used. However, the clinical significance of these data is, as yet, unclear. Although, in theory, adverse outcomes may have been associated with this practice, we could not confirm this with this database analysis.

Identification of cut-points for mild, moderate and severe pain due to diabetic peripheral neuropathy.

This study identified discrete categories of pain severity in a sample of patients with painful diabetic peripheral neuropathy (DPN), through derivation of cut-points on a 0-10 scale of pain severity (Brief Pain Inventory-DPN, BPI-DPN). Subjects were participants in a burden of illness survey (N=255). Serlin and colleagues' method establishing cut-points for cancer pain was adapted, considering all possible cut-points between 4 and 8. Optimal cut-points were those that created three pain severity categories producing maximum between-category differences on the seven BPI-DPN Interference items, using MANOVA. Cut-points of 4 and 7 optimally classified the sample for both Worst Pain and Average Pain, creating categories of mild, 0-3; moderate, 4-6; severe, 7 and higher (Hotelling's T(2)=22.95 and 16.20 for Worst and Average Pain, P<0.0001). Mean BPI-DPN Interference was 2.1 (SD=2.1), 4.9 (SD=1.9) and 7.4 (SD=1.6) for the mild, moderate and severe pain categories. Patients in the three categories differed significantly on patient-rated outcomes (Medical Outcomes Study Short Form-12v2 Mental and Physical Component Summaries and EuroQOL utility score), and on DPN-related healthcare visits (P<0.001). The labels 'mild, moderate and severe' Worst and Average Pain corresponded with patients' ratings of their pain using a verbal rating scale. This research shows that three categories of DPN pain severity can be identified based on interference with daily function, and that these categories are associated with patient outcomes and medical utilization.

Pain, medication use, and health-related quality of life in older persons with postherpetic neuralgia: results from a population-based survey.

UNLABELLED: Persons aged >65 years with pain caused by postherpetic neuralgia (PHN) were recruited via advertisements in 24 US newspapers and were mailed a questionnaire that addressed pain intensity (average, worst, least, current), pain interference (with general activity, mood, relations with other people, sleep, enjoyment of life), and health-related quality of life (using the EuroQoL health measure [EQ-5D] and a global rating scale). Respondents also were asked about their use of medication for shingles pain. A total of 385 persons completed the survey; 61% were >75 years of age. Mean (+/-standard deviation) duration of PHN was 3.3 (+/-4.0) years. Only about one half had taken prescription medication for shingles pain during the prior week; dosages were typically low. Mean average, worst, least, and current pain caused by shingles (0- to 10-point scale) was 4.6 (+/-2.1), 6.0 (+/-2.4), 2.9 (+/-2.3), and 4.0 (+/-2.7), respectively. Mean pain interference with general activity, mood, relations with other people, sleep, and enjoyment of life (0- to 10-point scale) was 3.7 (+/-3.1), 4.3 (+/-2.9), 3.0 (+/-2.8), 3.8 (+/-2.9), and 4.5 (+/-3.1), respectively. The mean EQ-5D health index score was 0.61; respondents rated their overall health as 65.7 (+/-21.1) on a 100-point scale. PHN causes substantial pain, dysfunction, and poor health-related quality of life in older persons, many of whom might be suboptimally treated. PERSPECTIVE: Many older persons (age >65 years) with PHN experience longstanding, severe, and debilitating pain and poor health-related quality of life; levels of dissatisfaction with treatment are high. Our study highlights the need for improved management of this disease.

Validation of a modified version of the brief pain inventory for painful diabetic peripheral neuropathy.

Neuropathic pain is the focus of current clinical research, clinical identification, and treatment. It is unique from nociceptive pain and requires evaluation of the relevance and utility of common pain measures created for other painful conditions. This study evaluated the psychometric properties of a modified Brief Pain Inventory (BPI) for patients with painful diabetic peripheral neuropathy (BPI-DPN). Participants were patients with painful DPN (n=255) enrolled in a DPN Burden of Illness survey referred through 17 outpatient settings (primary care physicians, endocrinologists, neurologists, and anesthesiologists). Patients completed the BPI-DPN, and self-report measures of health-related quality of life, mood sleep, and healthcare utilization. Construct, criterion and discriminant validity, and internal consistency reliability were evaluated. Principal axis factoring with oblimin rotation revealed two interpretable factors (eigenvalues>1.0), consistent with most published BPI validation studies; a severity scale comprising the four BPI Severity items and an interference scale comprising the seven Interference items, which satisfied criteria for interpretability and model fit. Cronbach's alpha was high (0.94) for both scales. Mean pain Severity was highly correlated with Bodily Pain from the Medical Outcomes Study Short Form-12, version 2 (rs=0.63, P < 0.001), the Pain/Discomfort item in the Euro-QoL (rs=0.58, P < 0.001), and a verbal rating scale measure of pain severity (rs=0.74, P < 0.001). Individual BPI-DPN Interference domains were moderately correlated (rs's >0.5, P < 0.001) with analogous measures, and the Sleep Interference item had a high, significant association with the three primary Medical Outcome Study-Sleep scale subscales (rs's=0.66-71, P < 0.001). Worst Pain and Interference ratings were significantly associated with hospital utilization and outpatient visits due to DPN. These results replicate, in a pure peripheral neuropathic pain condition, the BPI psychometric characteristics documented in populations with nociceptive or mixed pain conditions. The BPI-DPN is a promising instrument in the evaluation of painful DPN.

Pain severity in diabetic peripheral neuropathy is associated with patient functioning, symptom levels of anxiety and depression, and sleep.

Our goal was to evaluate pain severity, pain-related interference with function, sleep impairment, symptom levels of anxiety and depression, and quality of life among patients with painful diabetic peripheral neuropathy (DPN). Participants in a burden of illness survey (n = 255) completed the modified Brief Pain Inventory-DPN (BPI-DPN), MOS Sleep Scale, Hospital Anxiety and Depression Scale (HADS), Short Form Health Survey-12v2 (SF-12v2), and the EuroQoL (EQ-5D). Patients were 61 +/- 12.8 years old (51.4% female), had diabetes for 12 +/- 10.3 years and painful DPN for 6.4 +/- 6.4 years. Average and Worst Pain scores (BPI-DPN, 0-10 scales) were 5.0 +/- 2.5 and 5.6 +/- 2.8. Pain substantially interfered (>or=4 on 0-10 scales) with walking ability, normal work, sleep, enjoyment of life, mood, and general activity. Moderate to severe symptom levels of anxiety and depression (HADS-A and HADS-D scores >or=11 on 0-21 scales) occurred in 35% and 28% of patients, respectively. Patients reported greater sleep problems compared with the general U.S. population and significant impairment in both physical and mental functioning (SF-12v2) compared with subjects with diabetes. The mean EQ-5D utility score was 0.5 +/- 0.3. Greater pain levels in DPN (mild to moderate to severe) corresponded with higher symptom levels of anxiety and depression, more sleep problems, and lower utility ratings and physical and mental functioning, (all Ps < 0.01). Painful DPN is associated with decrements in many aspects of patients' lives: physical and emotional functioning, affective symptoms, and sleep problems. The negative impact is higher in patients with greater pain severity.

Validation of a modified version of the Brief Pain Inventory for painful diabetic peripheral neuropathy.

Neuropathic pain is the focus of current clinical research, clinical identification, and treatment. It is unique from nociceptive pain and requires evaluation of the relevance and utility of common pain measures created for other painful conditions. This study evaluated the psychometric properties of a modified Brief Pain Inventory (BPI) for patients with painful diabetic peripheral neuropathy (BPI-DPN). Participants were patients with painful DPN (n = 255) enrolled in a DPN Burden of Illness survey referred through 17 outpatient settings (primary care physicians, endocrinologists, neurologists, and anesthesiologists). Patients completed the BPI-DPN and self-report measures of health-related quality of life, mood sleep, and health care use. Construct, criterion and discriminant validity, and internal consistency reliability were evaluated. Principal axis factoring with oblimin rotation revealed two interpretable factors (eigenvalues > 1.0), consistent with most published BPI validation studies: a severity scale comprising the four BPI Severity items and an interference scale comprising the seven Interference items, which satisfied criteria for interpretability and model fit. Cronbach's alpha was high (0.94) for both scales. Mean pain Severity was highly correlated with Bodily Pain from the Medical Outcomes Study Short Form-12, version 2 (r(s) = 0.63, P < .001), the Pain/Discomfort item in the Euro-QoL (r(s) = 0.58, P < .001), and a verbal rating scale measure of pain severity (r(s) = 0.74, P < .001). Individual BPI-DPN Interference domains were moderately correlated (r(s)'s > 0.5, P < .001) with analogous measures, and the Sleep Interference item had a high, significant association with the three primary Medical Outcome Study-Sleep scale subscales (r(s)'s = 0.66-71, P < .001). Worst Pain and Interference ratings were significantly associated with hospital use and outpatient visits because of DPN. These results replicate, in a pure peripheral neuropathic pain condition, the BPI psychometric characteristics documented in populations with nociceptive or mixed pain conditions. The BPI-DPN is a promising instrument in the evaluation of painful DPN.

Development of a metric for a day of manageable pain control: derivation of pain severity cut-points for low back pain and osteoarthritis.

The objective of this study was to adapt the concept of 'episode-free day', a metric for measuring symptom relief in daily units, to the clinical outcome literature for persistent pain. The episode-free day metric is widely used in other medical literature, but no analogous measure exists in pain literature. Prior focus groups with this population suggested that a 'Day of Manageable Pain Control' was an appropriate name for the metric. In the present study, in order to derive a statistical criterion for 'Manageable Day', we used Serlin et al.'s (Pain 61 (1995) 277) cut-point derivation method to derive a single cut-point on a 0-10 scale of average pain that divided groups with significant persistent pain optimally on pain-related functional interference. Participants were 194 patients with moderate-severe low back pain (n=96) or osteoarthritis (n=98). For both patient samples, '5' was the cut-point that optimally distinguished groups on pain-related interference. '5-8' and '5-7' were double cut-point solutions that optimally divided LBP and OA samples into three categories (e.g. lowest, medium and highest average pain), respectively. Derived cut-points were confirmed using a variety of measures of functional disability. Together with research that showed that average pain ratings of approximately 5 and below permit increased function and quality of life in patients with moderate to severe low back pain and osteoarthritis, our findings provide support for the use of 0-5 on a 0-10 numeric average pain severity scale as one possible criterion for a Manageable Day.