Few studies have directly compared the clinical features of neuropathic and non-neuropathic pains. For this purpose, the French Neuropathic Pain Group developed a clinician-administered questionnaire named DN4 consisting of both sensory descriptors and signs related to bedside sensory examination. This questionnaire was used in a prospective study of 160 patients presenting with pain associated with a definite neurological or somatic lesion. The most common aetiologies of nervous lesions (n=89) were traumatic nerve injury, post herpetic neuralgia and post stroke pain. Non-neurological lesions (n=71) were represented by osteoarthritis, inflammatory arthropathies and mechanical low back pain. Each patient was seen independently by two experts in order to confirm the diagnosis of neuropathic or non-neuropathic pain. The prevalence of pain descriptors and sensory dysfunctions were systematically compared in the two groups of patients. The analysis of the psychometric properties of the DN4 questionnaire included: face validity, inter-rater reliability, factor analysis and logistic regression to identify the discriminant properties of items or combinations of items for the diagnosis of neuropathic pain. We found that a relatively small number of items are sufficient to discriminate neuropathic pain. The 10-item questionnaire developed in the present study constitutes a new diagnostic instrument, which might be helpful both in clinical research and daily practice.

This study describes the development and validation of the Neuropathic Pain Symptom Inventory (NPSI), a new self-questionnaire specifically designed to evaluate the different symptoms of neuropathic pain. Following a development phase and a pilot study, we generated a list of descriptors reflecting spontaneous ongoing or paroxysmal pain, evoked pain (i.e. mechanical and thermal allodynia/hyperalgesia) and dysesthesia/paresthesia. Each of these items was quantified on a (0-10) numerical scale. The validation procedure was performed in 176 consecutive patients with neuropathic pain of peripheral (n = 120) or central (n = 56) origin, recruited in five pain centers in France and Belgium. It included: (i) assessment of the test-retest reliability of each item, (ii) determination of the factorial structure of the questionnaire and analysis of convergent and divergent validities (i.e. construct validity), and (iii) evaluation of the ability of the NPSI to detect the effects of treatment (i.e. sensitivity to change). The final version of the NPSI includes 10 descriptors (plus two temporal items) that allow discrimination and quantification of five distinct clinically relevant dimensions of neuropathic pain syndromes and that are sensitive to treatment. The psychometric properties of the NPSI suggest that it might be used to characterize subgroups of neuropathic pain patients and verify whether they respond differentially to various pharmacological agents or other therapeutic interventions.

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The aim of this paper is to study the quality of verbal description and its diagnostic value in neuropathic pain. The verbal description of pain as assessed by a French adjective list questionnaire (QDSA) is compared between a group of 100 patients with neuropathic pain and a mixed group of 97 chronic benign and cancer non-neuropathic pain patients. Seventeen descriptors of the 61 QDSA descriptors have a significant intergroup frequency difference. By principal component analysis and Varimax rotation of the intercorrelation matrix of descriptors in the neuropathic group. 7 factors accounting for 66.0% of the total variance are derived. Six factors reflect purely sensory or affective aspects of the pain experience. Seven descriptors from the discriminant analysis function correctly assign 77% of neuropathic pain patients and 81% of the non-neuropathic pain patients. In a second neuropathic pain group of 32 patients, the discriminant function coefficient permits correct diagnostic categorization in 66% of the cases. Implications for clinical practice and trials are discussed.

The efficacy and safety of sustained-release tramadol compared to placebo in the treatment of post-herpetic neuralgia were evaluated in a multicenter, randomized, double-blind, parallel-group study in 127 outpatients. Treatment was administrated for 6 weeks. The dose of tramadol could be increased from 100 mg/day to 400 mg/day (300 mg/day in patients more than 75 years old). Groups were compared on changes in pain intensity on a Visual Analogue Scale (VAS) between inclusion and the 6th week of treatment (covariance analysis as main analysis and repeated measures analysis as complementary analysis) in the per protocol (PP) population. The randomized population comprised 127 patients aged 35-85 years, mostly females (72.4%). Groups were comparable at inclusion both in the intent to treat (ITT) population (63 patients in the tramadol group and 62 patients in the placebo group) and in the PP population (53 patients in the tramadol group and 55 patients in the placebo group). Mean pain intensity on day 43 adjusted on day 1 (covariance analysis) was significantly lower in the tramadol group than in the placebo group in both the PP (P=0.0499), and the ITT (P=0.031) populations. The two groups significantly differed on change in pain intensity over time (repeated measures analysis) in the ITT population (P=0.012). The percentage of pain relief over the 6th week was significantly higher in the tramadol group than in the placebo group (P=0.017). During the 6th week, patients in the tramadol group required less rescue medication than patients in the placebo group (P=0.022). No significant difference was found between groups either in pain intensity on a 5-point Verbal Scale (VRS) or in quality of life measurements. Tramadol was administered at an average dosage of 275.5 (89.7) mg/day after a 1-week dose-adaptation period. Tramadol was well tolerated. No notable difference appeared between groups either in the percentage of patients with treatment-associated adverse events (TAAE) (29.7% in the tramadol group and 31.8% in the placebo group) or in the total number of TAAE (31 in the tramadol group and 28 in the placebo group).

Four different French versions of the McGill Pain Questionnaire (MPQ) have been published: 3 are MPQ translations in Canadian French and 1 (QDSA) is an MPQ reconstruction in (France) French. The aim of our work was to study the validity of these available questionnaires for use in France. The validity was evaluated by 44 French physicians. Various validity criteria were studied: item, dimension, subclass and pain descriptor intensity. A new French MPQ was also developed. Significant validity differences emerged between the different MPQ versions. This study confirms the satisfactory validity of the QDSA. The validity of the newly developed French MPQ was equal but not better than the QDSA. A 15-item short MPQ-QDSA version was also developed. For studies with patients from France, it is recommended that the QDSA or the short MPQ-QDSA versions be used.

The purpose of this study was to compare the efficacy and tolerance of a single dose of the acetaminophen 400 mg-codeine 25 mg combination (ACC) aspirin 1000 mg (A) and a placebo (P) for the treatment of acute migraine attack. The study design was randomized, multicentre, double-blind and double dummy with cross-over on three periods. Of the 198 patients who had three attacks 29.8%, 52.3% and 49.7% had recorded the complete or almost complete disappearance of the pain at 2 h after P, A and ACC respectively. When compared with the placebo, the difference was significant for the A and ACC. When complete disappearance of pain at 2 h was used as a criterion, no significant difference was observed. These results enabled the sensitivity of the evaluation criteria suggested for clinical trials of migraine attack to be discussed.

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