title: The impact of fibromyalgia symptoms on brain morphometry.
abstract: Fibromyalgia (FMS) is a complex clinical syndrome that includes many symptoms beyond chronic pain. The studies that have addressed brain morphometry in FMS have had very heterogeneous results. Thus, the question of which specific FMS symptoms and clinical features-pain, but also psychological distress, sleep-related problems, health status, and medication intake-impact on brain morphometry remains open. Here, we wanted to determine if brain changes in FMS are "symptom-related" more than "diagnostic-related". We performed an observational study of 46 premenopausal women (23 FMS patients and 23 age-matched healthy participants). Magnetic resonance images were analyzed using voxel-based morphometry and subcortical segmentation. We used multiple regression models to assess the associations between total and local brain volumes and FMS clinical characteristics. Furthermore, we calculated associations between subcortical structures' shapes and volumes and FMS clinical characteristics. Larger psychological distress, anxiety, and sleepiness, and higher analgesic consumption accounted for 38 % of FMS patients' smaller total gray matter volume (GMV). For both groups, local decrements of GMV in the medial orbitofrontal cortex were associated to larger psychological distress. Local increases of GMV were positively related to pain scores (superior frontal gyrus), psychological distress (cerebellum), anxiety (medial orbitofrontal cortex), and sleepiness (frontal superior medial cortex). FMS clinical characteristics were also associated to deformations in subcortical structures and volumes changes. This study reveals that total and local GMV changes in FMS go beyond the traditional "pain matrix" alterations. We demonstrated that brain morphology is altered by pain, but also by clinical characteristics that define the FMS experience.
authors.affiliation: Mind, Brain, and Behavior Research Center-CIMCYC, University of Granada, Campus de Cartuja s/n, 18071, Granada, Spain. dipie@ugr.es.|College of Nursing & Health Innovation, Arizona State University, 550 N. 3rd St., 85004, Phoenix, AZ, USA. dipie@ugr.es.
authors.forename: Carolina
authors.initials: C
authors.lastname: Diaz-Piedra
authors.affiliation: Service of Rheumatology, University Hospital Virgen de las Nieves, Avda. de las Fuerzas Armadas 2, 18014, Granada, Spain.
authors.forename: Manuel A
authors.initials: MA
authors.lastname: Guzman
authors.affiliation: Mind, Brain, and Behavior Research Center-CIMCYC, University of Granada, Campus de Cartuja s/n, 18071, Granada, Spain.
authors.forename: Gualberto
authors.initials: G
authors.lastname: Buela-Casal
authors.affiliation: Mind, Brain, and Behavior Research Center-CIMCYC, University of Granada, Campus de Cartuja s/n, 18071, Granada, Spain.
authors.forename: Andres
authors.initials: A
authors.lastname: Catena
mesh_terms: D000328:Adult; D001007:Anxiety / Q000000981:diagnostic imaging; D001921:Brain / Q000000981:diagnostic imaging*; D059350:Chronic Pain / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000523:psychology; D005221:Fatigue / Q000000981:diagnostic imaging; D005260:Female; D005356:Fibromyalgia / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000523:psychology*; D066128:Gray Matter / Q000000981:diagnostic imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009473:Neuronal Plasticity; D009929:Organ Size; D010147:Pain Measurement; D011569:Psychiatric Status Rating Scales; D012044:Regression Analysis; D013315:Stress, Psychological / Q000000981:diagnostic imaging; D044465:White People
keywords: Chronic pain; Fibromyalgia; Gray matter volume; MRI; Neural plasticity