The effect of lacosamide in peripheral neuropathic pain: A randomized, double-blind, placebo-controlled, phenotype-stratified trial.

BACKGROUND: Neuropathic pain is common and difficult to treat. The sodium channel blocker lacosamide is efficacious in animal models of pain, but its effect on neuropathic pain in humans is inconclusive. METHODS: In a multicentre, randomized, double-blinded placebo-controlled phenotype stratified trial, we examined if lacosamide produced better pain relief in patients with the irritable nociceptor phenotype compared to those without. The primary outcome was the change in daily average pain from baseline to last week of 12 weeks of treatment. Secondary and tertiary outcomes included pain relief, patient global impression of change and presence of 30% and 50% pain reduction. RESULTS: The study was prematurely closed with 93 patients included and 63 randomized to lacosamide or placebo in a 2:1 ratio, of which 49 fulfilled the per protocol criteria and was used for the primary objective. We did not find a better effect of lacosamide in patients with the irritable nociceptor phenotype, the 95% CI for the primary objective was 0.41 (-1.2 to 2.0). For all patients randomized, lacosamide had no effect on the primary outcome, but significantly more patients were responders to lacosamide than during placebo, with an NNT of 4.0 (95% CI 2.3-16.1) and 5.0 (95% CI 2.8-24.5) for 30% and 50% pain reduction respectively. We did not identify any predictors for response. Lacosamide was generally well tolerated. CONCLUSION: We could not confirm that lacosamide was more efficacious in patients with the irritable nociceptor type, but the study was prematurely closed, so we cannot exclude a small difference. SIGNIFICANCE: Treatment of neuropathic pain is often a trial and error process. Little is known about which patient benefit from which kind of medication. The sodium channel blocker lacosamide shows variable effect on neuropathic pain. Pain sensory phenotype, as defined by quantitative sensory testing, did not predict response to treatment with lacosamide.

CSF Findings in Relation to Clinical Characteristics, Subtype, and Disease Course in Patients With Guillain-Barré Syndrome.

BACKGROUND AND OBJECTIVES: To investigate CSF findings in relation to clinical and electrodiagnostic subtypes, severity, and outcome of Guillain-Barré syndrome (GBS) based on 1,500 patients in the International GBS Outcome Study. METHODS: Albuminocytologic dissociation (ACD) was defined as an increased protein level (>0.45 g/L) in the absence of elevated white cell count (<50 cells/µL). We excluded 124 (8%) patients because of other diagnoses, protocol violation, or insufficient data. The CSF was examined in 1,231 patients (89%). RESULTS: In 846 (70%) patients, CSF examination showed ACD, which increased with time from weakness onset: ≤4 days 57%, >4 days 84%. High CSF protein levels were associated with a demyelinating subtype, proximal or global muscle weakness, and a reduced likelihood of being able to run at week 2 (odds ratio [OR] 0.42, 95% CI 0.25-0.70; p = 0.001) and week 4 (OR 0.44, 95% CI 0.27-0.72; p = 0.001). Patients with the Miller Fisher syndrome, distal predominant weakness, and normal or equivocal nerve conduction studies were more likely to have lower CSF protein levels. CSF cell count was <5 cells/µL in 1,005 patients (83%), 5-49 cells/µL in 200 patients (16%), and ≥50 cells/µL in 13 patients (1%). DISCUSSION: ACD is a common finding in GBS, but normal protein levels do not exclude this diagnosis. High CSF protein level is associated with an early severe disease course and a demyelinating subtype. Elevated CSF cell count, rarely ≥50 cells/µL, is compatible with GBS after a thorough exclusion of alternative diagnoses. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that CSF ACD (defined by the Brighton Collaboration) is common in patients with GBS.

Assessing Corneal Confocal Microscopy and Other Small Fiber Measures in Diabetic Polyneuropathy.

BACKGROUND AND OBJECTIVES: Damage to small nerve fibers is common in diabetic polyneuropathy (DPN), and the diagnosis of DPN relies on subjective symptoms and signs in a combination with objective confirmatory tests, typically electrophysiology or intraepidermal nerve fiber density (IENFD) from skin biopsy. Corneal confocal microscopy (CCM) has been introduced as a tool to detect DPN. However, it is unclear if CCM can reliably be used to diagnose DPN and how the technique compares with other commonly used measures of small fiber damage, such as IENFD, cold detection threshold (CDT), and warm detection threshold (WDT). Therefore, we assessed and compared the use of CCM, IENFD, CDT, and WDT in the diagnosis of DPN in patients with type 2 diabetes. METHODS: In this cohort study, the participants underwent detailed neurologic examination, electrophysiology, quantification of IENFD, CCM, and quantitative sensory testing. Definition of DPN was made in accordance with the Toronto criteria for diabetic neuropathy (without relying on IENFD and thermal thresholds). RESULTS: A total of 214 patients with at least probable DPN, 63 patients without DPN, and 97 controls without diabetes were included. Patients with DPN had lower CCM measures (corneal nerve fiber length [CNFL], nerve fiber density, and branch density), IENFD, CDT, and WDT compared with patients without DPN (p ≤ 0.001, <0.001, 0.002, p < 0.001, p = 0.003, and <0.005, respectively), whereas there was no difference between controls and patients with diabetes without DPN. All 3 CCM measures showed a very low diagnostic sensitivity with CNFL showing the highest (14.4% [95% CI 9.8-18.4]) and a specificity of 95.7% (88.0-99.1). In comparison, the sensitivity of abnormal CDT and/or WDT was 30.5% (24.4-37.0) with a specificity of 84.9% (74.6-92.2). The sensitivity of abnormal IENFD was highest among all measures with a value of 51.1% (43.7-58.5) and a specificity of 90% (79.5-96.2). CCM measures did not correlate with IENFD, CDT/WDT, or neuropathy severity in the group of patients with DPN. DISCUSSION: CCM measures showed the lowest sensitivity compared with other small fiber measures in the diagnosis of DPN. This indicates that CCM is not a sensitive method to detect DPN in recently diagnosed type 2 diabetes. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that CCM measures aid in the detection of DPN in recently diagnosed type 2 diabetics but with a low sensitivity when compared with other small fiber measures.

Comparison of diabetic and idiopathic sensory polyneuropathies with respect to nerve fibre affection and risk factors.

Background and purpose: Chronic distal sensory or sensorimotor polyneuropathy is the most common pattern of polyneuropathy. The cause of this pattern is most often diabetes or unknown. This cross-sectional study is one of the first studies to compare the demographics, cardiovascular risk factors and clinical characteristics of diabetic polyneuropathy (DPN) with idiopathic polyneuropathy (IPN). Methods: Patients with DPN were included from a sample of 389 patients with type 2 diabetes mellitus (T2DM) enrolled from a national cohort of patients with recently diagnosed T2DM (Danish Centre for Strategic Research in Type 2 Diabetes cohort). Patients with IPN were included from a regional cohort of patients with symptoms of polyneuropathy referred for workup at a combined secondary and tertiary neurological centre (database cohort). Results: A total of 214 patients with DPN were compared with a total of 88 patients with IPN. Patients with DPN were older (67.4 vs 59 years) and had a longer duration of neuropathy symptoms. Patients with DPN had greater body mass index (32 vs 27.4 kg/m2) and waist circumference (110 cm vs 97 cm); higher frequency of hypertension diagnosis (72.9% vs 30.7%); lower total cholesterol, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol levels; and a higher prevalence of use of statins (81.8% vs 19.3%). DPN was associated with a slightly higher autonomic score and total score on the Neuropathy Symptom Score; lower frequency of hyperalgesia, allodynia and decreased vibration on quantitative sensory testing; lower intraepidermal nerve fibre density count and higher frequency of small-fibre neuropathy. Conclusion: DPN and IPN showed clear differences in neuropathy characteristics, indicating that these two entities are to be regarded as aetiologically and pathogenetically distinct.

Association Between Incident Cancer and Guillain-Barré Syndrome Development: A Nationwide Case-Control Study.

BACKGROUND AND OBJECTIVES: Cancer may increase the risk of developing Guillain-Barré syndrome (GBS) due to molecular mimicry or immunosuppression, but the exact relationship is unclear. We aimed to determine the association between incident cancer and the following risk of GBS development. METHODS: We conducted a nationwide population-based case-control study of all patients with first-time hospital-diagnosed GBS in Denmark between 1987 and 2016 and 10 age-, sex-, and index date-matched population controls per case. We identified incident cancer diagnoses between 6 months before and 2 months after the GBS index date. We used conditional logistic regression to compute odds ratios (ORs) as a measure of relative risk and performed stratified analyses to assess the impact of cancer on GBS risk in strata of calendar periods, sex, and age. In sensitivity analyses, to assess any potential risk of survival bias induced by including cancer diagnoses potentially made after GBS diagnosis, we examined incident cancers in both a broader exposure window (1 year before to 3 months after GBS index date) and a narrower window (6 months to 1 month before the GBS index date). RESULTS: Of the 2,414 patients with GBS and 23,909 controls included, 49 cases (2.0%) and 138 controls (0.6%) had a recent cancer diagnosis, yielding a matched OR of 3.6 (95% CI 2.6-5.1) for GBS associated with cancer. Stratification by calendar time, sex, and age showed robust results for the association between cancer and GBS, with no major variations. Broadening and narrowing the exposure window produced slightly weakened associations of OR of 2.4 (95% CI 1.8-3.3) and 2.5 (95% CI 1.5-4.1), respectively. The GBS ORs were highest for cancers of the lymphatic and hematopoietic tissue (OR 7.2, 95% CI 2.9-18.0), respiratory tract (OR 5.6, 95% CI 2.7-11.9), prostate and other male genital organ (OR 5.0, 95% CI 2.1-11.6), and breast (OR 5.0, 95% CI 1.7-14.5) cancer. DISCUSSION: In this large nationwide epidemiologic study, incident cancer was associated with a markedly increased risk of subsequent GBS development. The results suggest that as-yet unidentified factors present in several types of cancer drive this association.

The characteristics of pain and dysesthesia in patients with diabetic polyneuropathy.

INTRODUCTION/AIMS: Patients with diabetic polyneuropathy (DPN) may experience paresthesia, dysesthesia, and pain. We aimed to characterize the predictors, symptoms, somatosensory profile, neuropathy severity, and impact of painful DPN and dysesthetic DPN. METHODS: This study was a cross-sectional study of type 2 diabetes patients with confirmed DPN, diagnosed using widely accepted methods including a clinical examination, skin biopsy, and nerve conduction studies. FINDINGS: Of 126 patients with confirmed DPN, 52 had DPN without pain or dysesthesia, 21 had dysesthetic DPN, and 53 painful DPN. Patients with painful DPN were less physically active and suffered from more pain elsewhere than in the feet compared to patients with DPN without pain. Patients with painful DPN had the largest loss of small and large sensory fiber function, and there was a gradient of larger spatial distribution of sensory loss from DPN without dysesthesia/pain to dysesthetic DPN and to painful DPN. This could indicate that patients with dysesthesia had more severe neuropathy than patients without dysesthesia but less than patients with painful DPN. Patients with dysesthetic and painful DPN had higher symptom scores for depression and fatigue than those without dysesthesia/pain with no difference between dysesthetic and painful DPN. CONCLUSIONS: There was a gradient of increasing sensory loss from DPN without dysesthesia/pain to dysesthetic DPN and to painful DPN. Pain and dysesthesia are common in DPN and both interfere with daily life. It is therefore important to consider dysesthesia when diagnosing and treating patients with neuropathy.

Small and large fiber sensory polyneuropathy in type 2 diabetes: Influence of diagnostic criteria on neuropathy subtypes.

Diabetic polyneuropathy (DPN) can be classified based on fiber diameter into three subtypes: small fiber neuropathy (SFN), large fiber neuropathy (LFN), and mixed fiber neuropathy (MFN). We examined the effect of different diagnostic models on the frequency of polyneuropathy subtypes in type 2 diabetes patients with DPN. This study was based on patients from the Danish Center for Strategic Research in Type 2 Diabetes cohort. We defined DPN as probable or definite DPN according to the Toronto Consensus Criteria. DPN was then subtyped according to four distinct diagnostic models. A total of 277 diabetes patients (214 with DPN and 63 with no DPN) were included in the study. We found a considerable variation in polyneuropathy subtypes by applying different diagnostic models independent of the degree of certainty of DPN diagnosis. For probable and definite DPN, the frequency of subtypes across diagnostic models varied from: 1.4% to 13.1% for SFN, 9.3% to 21.5% for LFN, 51.4% to 83.2% for MFN, and 0.5% to 14.5% for non-classifiable neuropathy (NCN). For the definite DPN group, the frequency of subtypes varied from: 1.6% to 13.5% for SFN, 5.6% to 20.6% for LFN, 61.9% to 89.7% for MFN, and 0.0% to 6.3% for NCN. The frequency of polyneuropathy subtypes depends on the type and number of criteria applied in a diagnostic model. Future consensus criteria should clearly define sensory functions to be tested, methods of testing, and how findings should be interpreted for both clinical practice and research purpose.

Pediatric Guillain-Barré Syndrome in a 30-Year Nationwide Cohort.

BACKGROUND: Guillain-Barré syndrome is the most common cause of acute flaccid paresis in childhood. Few validated large-scale population-based data are available concerning pediatric Guillain-Barré syndrome, including incidence, risk factors, and initial clinical characteristics. METHODS: In the Danish National Patient Registry, we identified all children aged below 16 years (N = 212) diagnosed with Guillain-Barré syndrome and admitted to any Danish department of pediatrics between 1987 and 2016. A total of 145 (68%) medical files could be retrieved and reviewed, enabling classification of patients with true Guillain-Barré syndrome. The nationwide Guillain-Barré syndrome incidence rate was calculated and stratified by age, gender, time periods, and season. Risk factors and initial Guillain-Barré syndrome characteristics were assessed by medical record review. RESULTS: The positive predictive value of Guillain-Barré syndrome diagnosis codes was 86%. The crude Guillain-Barré syndrome incidence rate was 0.69 per 100,000 person years and peaked at two years of age. The incidence rate was higher among men (0.80) than women (0.58) and was relatively stable over the 30-year period. No seasonal difference of the incidence rate was found. Of the 125 Guillain-Barré syndrome cases, 63% were preceded by infection, whereas none were preceded by surgery or malignant disease. Medically treated pain was documented in 70%, mainly confined to the lower extremities. CONCLUSIONS: Pediatric Guillain-Barré syndrome diagnoses in the Danish National Patient Registry have high validity, the incidence peaks at age two years, and is preceded by infection in two-thirds of children. Lower extremity pain is a common clinical presentation in the acute setting.

Statin use and peripheral nerve function-A prospective follow-up study.

PURPOSE: To examine the association between use of statins and risk of deterioration of peripheral nerve function. METHODS: We prospectively followed patients who initiated statin treatment and compared them with statin never-users (non-users). At the time of inclusion and at 1-year follow-up, participants underwent tests for peripheral nerve function (ie nerve conduction studies, quantitative sensory testing), skin biopsies and ratings of symptoms and signs of neuropathy. We selected five tests of nerve function and the intraepidermal nerve fibre density (IENFD) a priori as primary outcomes. We used linear regression to test for differences between statin users and non-users with Holm-Bonferroni-corrected statistical significance level of .05. RESULTS: Comparisons were based on 57 statin users and 46 non-users. Changes in nerve function test results during follow-up were not uniform with regard to direction and were statistically not significant with the exception of IENFD (change in IENFD: statin users 1 fibre/mm vs. non-statin users -2 fibres/mm; P-value = .006). None of the participants developed overt peripheral neuropathy. However, five statin users developed neuropathy-like symptoms and a post hoc analysis showed a significant decrease in vibration sensitivity compared to asymptomatic statin users. CONCLUSION: Statin use was not clearly associated with increased risk of deterioration of peripheral nerve function analysed at a group level. However, given the sample size limitations of our study and the findings of our post hoc analysis, we cannot preclude that peripheral nerve function may be affected in some individuals exposed to statins.

Diabetic polyneuropathy and pain, prevalence, and patient characteristics: a cross-sectional questionnaire study of 5,514 patients with recently diagnosed type 2 diabetes.

Most studies of diabetic polyneuropathy (DPN) and painful DPN are conducted in persons with longstanding diabetes. This cross-sectional study aimed to estimate the prevalence of DPN and painful DPN, important risk factors, and the association with mental health in recently diagnosed type 2 diabetes. A total of 5514 (82%) patients (median diabetes duration 4.6 years) enrolled in the Danish Centre for Strategic Research in Type 2 Diabetes cohort responded to a detailed questionnaire on neuropathy and pain. A score ≥4 on the MNSI questionnaire determined possible DPN, whereas pain presence in both feet together with a score ≥3 on the DN4 questionnaire determined possible painful DPN. The prevalence of possible DPN and possible painful DPN was 18% and 10%, respectively. Female sex, age, diabetes duration, body mass index, and smoking were associated with possible DPN, whereas only smoking showed a clear association with possible painful DPN (odds ratio 1.52 [95% confidence interval: 1.20-1.93]). Possible DPN and painful DPN were independently and additively associated with lower quality of life, poorer sleep, and symptoms of depression and anxiety. Possible DPN itself had greater impact on mental health than neuropathic pain. This large study emphasizes the importance of careful screening for DPN and pain early in the course of type 2 diabetes.

[Chronic inflammatory demyelinating polyneuropathy].

In this review, we discuss chronic inflammatory demyelinating polyneuropathy (CIDP), which is a disease with proximal and distal weakness and sensory disturbances resulting in impaired daily activity. The diagnosis is based on the clinical presentation and electrophysiology demonstrating demyelination in the peripheral nerves. CIDP can be successfully treated with immunoglobulin, glucocorticoids or plasma exchange, and during the latest decade, immunoglobulin has been administered subcutaneously improving patients' flexibility and autonomy. By time, 30% of the patients will remit, and maintenance treatment will no longer be necessary.

Guillain-Barré syndrome in Denmark: validation of diagnostic codes and a population-based nationwide study of the incidence in a 30-year period.

Purpose: To validate the diagnostic codes for Guillain-Barré syndrome (GBS) in the Danish National Patient Registry (DNPR). Secondly, to examine 30-year trends in the incidence of GBS in Denmark. Patients and methods: We used the DNPR to identify all patients aged 16 and above diagnosed with a primary GBS diagnosis at any Danish department of neurology between 1987 and 2016. Medical files were reviewed according to the clinical criteria of the National Institute of Neurological Disorders and Stroke Committee and classified according to the Brighton criteria. The incidence rate (IR) was calculated based on data from 1987 to 2016 and stratified by season, gender, and age. Results: Over 30 years, we identified 2,319 patients aged 16 and above in the DNPR. From a validation cohort of 573 patients, we were able to retrieve 425 (74.2%) medical files; 356 GBS diagnoses were confirmed. The overall positive predictive value was 83.8% (95% confidence interval (CI): 80.0-87.0). In 99% of the confirmed patients, the Brighton criteria level 1-3 for GBS were met. The IR was fairly stable over 30 years at 1.77 per 100,000 person years (95% CI: 1.70-1.84). The incidence was higher in the winter season (IR ratio compared with summer: 1.18 (95% CI: 1.09-1.29)), and was strongly associated with male gender (IR ratio vs females: 1.44 (95% CI: 1.33-1.57)). IRs rose with age at diagnosis, particularly after the age of 50 in both men and women and a minor peak was observed for total IR in young adults. Conclusion: Primary diagnostic codes for GBS at Danish departments of neurology have high validity. The DNPR is a well-suited data source for epidemiological research on GBS. The Danish nationwide 30-year GBS IR is stable over time and similar to GBS IRs reported in other European and North American populations.

Statins and polyneuropathy revisited: case-control study in Denmark, 1999-2013.

AIM: In a previous study, we found a positive association between statin use and polyneuropathy risk. Other studies reported equivocal results. The present study aimed to confirm our findings with a design similar to that used in our previous study but with a larger data set. METHODS: We searched medical registry data to identify patients diagnosed with incident polyneuropathy of no known cause (idiopathic polyneuropathy) between 1999 and 2013; we verified diagnoses through medical records. For each case, we recruited 20 general population controls with no previous history of polyneuropathy. Controls were matched to their respective case for age and gender. We ascertained the prior statin use of cases and controls through a prescription registry. Based on this information, exposure to statins was categorized into 'ever use' or 'never use'. Ever use of statins was classified by how recently they had been used ('current use' or 'past use'); current use was further classified into long-term use (5+ years) and high- or low-intensity use. We used conditional logistic regression to calculate odds ratios (ORs) with 95% confidence intervals (CIs) to examine associations between polyneuropathy and statin use. RESULTS: We included 370 validated cases and 7400 controls. Ever use of statins was not associated with an elevated risk of polyneuropathy (OR 1.14, 95% CI 0.84, 1.54). Similarly, we found no associations between polyneuropathy risk and current use (OR 1.11, 95% CI 0.79, 1.53), long-term use (OR 1.13, 95% CI 0.66, 1.92) or high-intensity statin use (OR 1.05, 95% CI 0.59, 1.84). CONCLUSION: Statin use was not associated with an increased risk of idiopathic polyneuropathy.

[Skin biopsy and quantitative sensory testing can contribute to small fibre neuropathy diagnostics].

Nerve conduction studies are normal in small fibre neuropathy and special methods such as skin biopsies or quantitative sensory testing are required for diagnosis. In skin biopsies, nerve fibres are stained immunohistochemically and loss of distal nerve endings can be quantified directly. Assessment of thermal detection thresholds is used to evaluate the function of the sensory thermal pathways, but cannot discriminate between central and peripheral lesions. Small fibre neuropathy is often associated with potentially treatable diseases, and treatment of neuropathic pain may be required.

[Myoclonus as a side effect to citalopram treatment in a patient with liver cirrhosis]. / Patient med nedsat leverfunktion fikmyoklonier under behandling medselektive serotoningenoptagelseshæmmere.

Side effects such as myoclonus and tremor are rare when treating with selective serotonin reuptake inhibitors (SSRIs). We present a case where a patient with known liver cirrho-sis and in treatment with citalopram developed myoclonus, tremor and gait difficulties. The symptoms were reduced when the SSRI dose was decreased. In patients with unexplained movement disorders the usage of SSRIs should be considered as a cause. Furthermore, treatment with SSRIs should be carefully assessed in patients with reduced liver function.

[A syndrome of chronic ataxic polyneuropathy, ophtalmoplegia, IgM paraprotein, cold agglutinins and anti-disialosyl antibodies can cause diplopia in patients with chronic sensory polyneuropathy]. / Monoklonal gammopati af ukendt signifikans kan medføre polyneuropati og oftalmoplegi.

CANOMAD is a rare syndrome of chronic ataxic polyneuropathy, ophtalmoplegia, IgM paraprotein, cold agglutinins and anti-disialosyl antibodies. We present a case of a 65-year-old woman with clinical and electrophysiological features of chronic sensory polyneuropathy and diplopia. Serum samples from the patient contained IgM paraprotein and anti-GM2-antibodies. Treatment with intravenous immunoglobulins resulted in an improvement of the patient's diplopia and polyneuropathy. The case shows the importance of considering CANOMAD as a cause of diplopia in patients with chronic sensory polyneuropathy.

Recent advances in pharmacological treatment of neuropathic pain.

Recent studies investigating the pharmacological management of neuropathic pain support the efficacy of certain antidepressants, anticonvulsants, and opioids. Novel directions in drug applications include topical applications of patches with either lidocaine or capsaicin and intradermal injections of botulinum toxin. In cases of partial pain relief, drug combinations may be considered.

The evidence for pharmacological treatment of neuropathic pain.

Randomized, double-blind, placebo-controlled trials on neuropathic pain treatment are accumulating, so an updated review of the available evidence is needed. Studies were identified using MEDLINE and EMBASE searches. Numbers needed to treat (NNT) and numbers needed to harm (NNH) values were used to compare the efficacy and safety of different treatments for a number of neuropathic pain conditions. One hundred and seventy-four studies were included, representing a 66% increase in published randomized, placebo-controlled trials in the last 5 years. Painful poly-neuropathy (most often due to diabetes) was examined in 69 studies, postherpetic neuralgia in 23, while peripheral nerve injury, central pain, HIV neuropathy, and trigeminal neuralgia were less often studied. Tricyclic antidepressants, serotonin noradrenaline reuptake inhibitors, the anticonvulsants gabapentin and pregabalin, and opioids are the drug classes for which there is the best evidence for a clinical relevant effect. Despite a 66% increase in published trials only a limited improvement of neuropathic pain treatment has been obtained. A large proportion of neuropathic pain patients are left with insufficient pain relief. This fact calls for other treatment options to target chronic neuropathic pain. Large-scale drug trials that aim to identify possible subgroups of patients who are likely to respond to specific drugs are needed to test the hypothesis that a mechanism-based classification may help improve treatment of the individual patients.

Intensive community pharmacy intervention had little impact on triptan consumption: a randomized controlled trial.

OBJECTIVE: To evaluate the impact of an intensive pharmaceutical care campaign targeting inappropriate use of triptans. DESIGN: Randomized controlled trial. SETTING: 22 community pharmacies in the County of Funen, Denmark. SUBJECTS: A total of 1123 triptan users at intervention pharmacies and 1340 at control pharmacies. INTERVENTION: Intervention pharmacy staff received information on migraine and other types of headache, detection of inappropriate triptan use and other drug-related problems, and techniques for establishing a dialogue with patients. Intervention consisted of a folder and a structured dialogue with the pharmacy staff. The folder included questions aimed at detecting overuse and inappropriate triptan use. MAIN OUTCOME MEASURES: Change in average triptan consumption in doses per month measured by means of a prescription database with information on all purchases of reimbursed drugs at the level of the individual patient. RESULTS: Overall, intervention had no statistically significant short-term impact on patients' consumption of triptans either among incident users (intervention/control ratio 1.02; 95% confidence interval 0.95 to 1.12), or among prevalent users (1.02; 0.97 to 1.08). No effects were observed after 6 and 9 months, apart from a possible borderline effect after 9 months among prevalent users with intermediate triptan consumption (0.93; 0.87 to 1.00). CONCLUSION: The pharmaceutical care campaign did not reduce the use of triptans.

Symptoms and signs in patients with suspected neuropathic pain.

The study sought to determine if symptoms and signs cluster differentially in groups of patients with increasing evidence of neuropathic pain (NP). We prospectively looked at symptoms and signs in 214 patients with suspected chronic NP of moderate to severe intensity. According to a set of clinical criteria the patients were a priori classified as having the so-called 'Definite NP' (n = 91), 'Possible NP' (n = 71), or 'Unlikely NP' (n = 52). A recording of symptoms including pain descriptors, intensity of five categories of pain, Short Form McGill Pain Questionnaire, and Major Depression Inventory were done. Sensory tests including repetitive pinprick stimulation, examination for cold-evoked pain by an acetone drop and brush-evoked pain were carried out in the maximal pain area and in a control area. High intensity of superficial ongoing pain, and touch or cold provoked pain was associated with chronic pain classified as definite or possible neuropathic. Intensity of deep ongoing pain, and 'paroxysms' was similar in the three groups. Brush-evoked pain was more frequent in definite NP. The McGill Pain Questionnaire and the used pain descriptors could not distinguish between the three clinical categories. Although certain symptoms (touch or cold provoked pain) and signs (brush-evoked allodynia) are more prominent in patients with definite or possible NP, we found considerable overlap with the clinical presentation of patients with unlikely NP.