Pain assessment in Charcot-Marie-Tooth (CMT) disease

Abstract Objective The objective of our study was to describe and evaluate the prevalence of chronic pain in persons with Charcot-Marie-Tooth (CMT) disease during a multidisciplinary consultation at the Center of Reference for Neuromuscular Diseases. Methodology This prospective study was conducted between 2008 and 2010, it was a partnership between a Center of Reference for Neuromuscular Diseases (Centre de référence des maladies neuromusculaires [CRMD]) and a Department for the Assessment and Treatment of Pain (Département d’évaluation et de traitement de la douleur [DETD]). The evaluation consisted in a complete assessment of each patient during the first multidisciplinary consultation, with a previously established diagnosis validated by genetic testing, by various specialists: neurologist, PM&R physician, pain management specialist and physiotherapist. The evaluation tools used were Visual Analogical Scale (VAS), Hospital Anxiety and Depression Scale (HAD), DN4 scale, Neuropathic Pain Symptom Inventory (NPSI) (if DN4 ≥ 4), Pain Questionnaire of Saint Antoine (QDSA) (if DN4 < 4), body representation to define the painful areas, Overall Neuropathy Limitations Scale (ONLS), Medical Research Council scale (MRC), Short Questionnaire on Pain (QCD), VAS during transfers, self-care, getting dressed and physiotherapy sessions and quantified use of analgesics. Results A total of 50 patients were included (28 women, 22 men); two patients (one man and one woman) were discarded from the study because of missing pain assessment data. Mean age was 47 years (R: 14–85), in average the symptoms had been present for the past 20 years (R: 0.3–68), most patients had little impairment, the mean MRC was 53 (R: 36–60), with CMT1A being predominant (CMT1A: 76.9%, CMTX: 13.5%, CMT2: 5.8%, CMT4: 3.8%). It is noted that 65.4% of patients reported some pain with a mean duration of pain at 140 months (R: 5–660). The mean VAS was 5.5 (R: 1–10), greater than 4 in 79.4% of cases, requiring the use of analgesics in 38.4% of cases (step 1: 60%, step 2: 40% on the WHO pain relief ladder). The predominant location of the pain was distal, peripheral and symmetric (64.7%); furthermore the feet were affected in 80% of cases. DN4 was positive in 40.6% of painful patients. In 62.5% of the cases, the pain did not have an underlying mechanical origin. The emotional impact remained quite modest (HAD: A = 8; D = 5). Patients with CMT1A seemed less affected by pain ( P = 0.03). Conclusion This ori