Morphological brain alterations in subgroups of fibromyalgia patients
HC Aster1, D. Evdokimov1, A. Braun1, N. Üçeyler1, G. Homola2, T. Kampf2, M. Pham2, C. Sommer1

1Dept of Neurology, University Hospital Würzburg, Germany
2Dept of Neuroradiology, University Hospital Würzburg, Germany 

Background and aims: Despite of decades of research there is still no clear understanding of the pathophysiology of fibromyalgia syndrome (FMS). While there has been evidence that some FMS patients have deficits in peripheral small nerve fiber function and morphology, other studies show alterations in pain processing of the central nervous system. The aim of our study is to investigate the central and peripheral nervous system in the same patients in order to identify possible interactions.

Methods: This prospective case-control study included female patients, diagnosed with FMS according to the 2010 ACR guidelines (n=40) and a healthy, age and sex matched control group (HC, n=40). MR imaging of the brain included functional and structural sequences. Skin biopsies were taken to evaluate the intraepidermal small nerve fiber density (IENFD). 

Results: We found no significant differences in FMS patients compared to controls . The subgroup analysis showed that patients with low IENFD compared to patients with normal IENFD had lower gray matter volumes in the superiorfrontal cortex (p<0.04).
Conclusions: Our data suggest that the fibromyalgia symptoms are related to pathophysiology in both the peripheral and central nervous system. Furthermore, our results suggest that patients with the more pronounced phenotype in the periphery also show more pathological patterns in the brain structure.

MORPHOLOGICAL BRAIN ALTERATIONS IN SUBGROUPS OF FIBROMYALGIA PATIENTS