Comparison of pain syndromes associated with nervous or somatic lesions and development of a new neuropathic pain diagnostic questionnaire (DN4)

TLDR

Few studies have directly compared the clinical features of neuropathic versus non‑neuropathic pain. The study aimed to develop the DN4 questionnaire, a clinician‑administered tool combining sensory descriptors and bedside examination signs. The DN4 was applied prospectively to 160 patients with neurological or somatic lesions, diagnoses were confirmed by two independent experts, and its psychometric properties were evaluated through face validity, inter‑rater reliability, factor analysis, and logistic regression. A small subset of items was found sufficient to discriminate neuropathic pain, resulting in a 10‑item DN4 questionnaire useful for clinical research and practice.

Abstract

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.