Update on laser-evoked potential findings in fibromyalgia patients in light of clinical and skin biopsy features

• DOI: 10.1007/s00415-013-7211-9
• Publication Date: 2013-12-23T13:30:04Z
• Authors: Marina de Tommaso; Maria Nolano; Florenzo Iannone; Eleonora Vecchio; Katia Ricci; Marta Lorenzo; Marianna Delussi; Francesco Girolamo; Vito Lavolpe; Vincenzo Provitera; Annamaria Stancan...; Giovanni Lapadula; Paolo Livrea
• Keywords: Fibromyalgia; Laser-evoked potentials; Peripheral and central nervous system dysfunction; Skin biopsy; Adult; Biopsy; Brain; Comorbidity; Electroencephalography; Electrooculography; Epidermis; Female; Fibromyalgia; Habituation, Psychophysiologic; Humans; Laser-Evoked Potentials; Male; Middle Aged; Migraine Disorders; Neural Conduction; Pain; Pain Measurement; Quality of Life; Random Allocation; Neurology; Neurology (clinical); Adult; Male; Epidermi; Peripheral and central nervous system dysfunction; Fibromyalgia; Biopsy; Migraine Disorders; Neural Conduction; 610; Pain; Comorbidity; Random Allocation; 03 medical and health sciences; Laser-Evoked Potentials; 0302 clinical medicine; Migraine Disorder; Skin biopsy; Humans; Habituation, Psychophysiologic; Pain Measurement; Psychophysiologic; Medicine (all); Laser-evoked potentials; Brain; 600; Electroencephalography; Middle Aged; Laser-evoked potential; Electrooculography; Neurology; Epidermal Cells; Quality of Life; Female; Habituation; Neurology (clinical); Epidermis; Human

In fibromyalgia (FM), reduced habituation of laser-evoked potentials (LEPs) suggests a dysfunction of pain processing at a central level. In this study, we aimed to further examine the nociceptive pathways at the peripheral to the central level in a large group of FM patients by means of LEPs and skin biopsy, in light of healthy controls findings and main clinical features. One hundred and ninety-nine FM patients and 109 age- and sex-matched controls were submitted to LEPs by the dorsum of the right hand and the skin over the right chest and knee tender point stimulation. Skin biopsy was performed in 21 randomly selected FM patients and 60 age- and sex-matched controls. The mean N2-P2 amplitude was reduced in the whole FM group, with normal or even increased values in patients with migraine as comorbidity and reduced values in other patients including those presenting with distal sensory deficits. All patients had reduced N2-P2 habituation in respect to controls. In the FM group, LEPs habituation was correlated with pain at tender points and bad quality of life. Epidermal fiber density was significantly reduced in FM patients versus controls, and correlated with N2-P2 amplitude by the hand and chest tender-point stimulation. Dysfunction in the nociceptive system at both the central and peripheral levels may concur to explain phenotypical eterogeneity and clinical symptom complexity in fibromyalgia.