Marianna Papadopoulou1,2, Apostolos Papapostolou3, Eleni Bakola4, Vasilios G Masdrakis5, Christos Moschovos4, Elisabeth Chroni6, Georgios Tsivgoulis4, Ioannis Michopoulos7. 1. Second Department of Neurology, Medical School, National and Kapodistrian University of Athens Attikon University General Hospital, Athens, Greece. marpapgr@yahoo.co.uk. 2. Department of Physiotherapy, Laboratory of Neuromuscular and Cardiovascular Study of Motion, University of West Attica, 28 Ag. Spyridonos, 12243, Athens, Greece. marpapgr@yahoo.co.uk. 3. Private Practice, Athens, Greece. 4. Second Department of Neurology, Medical School, National and Kapodistrian University of Athens Attikon University General Hospital, Athens, Greece. 5. First Department of Psychiatry, Medical School, National and Kapodistrian University of Athens, Eginition Hospital, Athens, Greece. 6. Department of Neurology, School of Medicine, University of Patras, Rio-Patras, Greece. 7. Second Department of Psychiatry, Medical School, National and Kapodistrian University of Athens, Attikon University General Hospital, Athens, Greece.
Abstract
BACKGROUND: Fibromyalgia (FM) and generalized anxiety disorder (GAD) share common clinical features: they both affect women more than men, their diagnosis is based solely on clinical criteria, and some of the symptoms such as anxiety, aches and muscle tension, sleep disorders, and cognitive dysfunction occur in both diseases. For both conditions, an underlying dysregulation of the autonomic nervous system (ANS) has been proposed. OBJECTIVE: The aims of this study were to investigate ANS dysfunction in FM and GAD and compare them with controls. METHODS: Sympathetic skin response (SSR) from palm and sole and cross-sectional area (CSA) of bilateral vagus nerves (VN) were measured in 28 healthy controls, 21 FM patients, and 24 GAD patients. RESULTS: CSA of VN was significantly smaller in FM patients (right: 1.97 ± 0.74mm2, left: 1.75 ± 0.65 mm2) and GAD patients (right: 2.12 ± 0.97mm2, left: 1.71 ± 0.86 mm2) compared to controls (right: 3.21 ± 0.75 mm2, left: 2.65 ± 1.13 mm2, p < 0.001, but did not differ between the two patient groups. SSR parameters were similar between patients and controls. SSR latency correlated to clinical scales (FM Widespread Pain Index) in the FM group (r = 0.515, p = 0.02 and r = 0.447, p = 0.05) for the upper and lower limbs respectively, but no other correlation between clinical and neurophysiological parameters was identified. CONCLUSION: This study confirms similar ANS abnormalities in FM and GAD that fairly distinguish them from controls and support the hypothesis of a common pathophysiological substrate underlying both conditions.
BACKGROUND: Fibromyalgia (FM) and generalized anxiety disorder (GAD) share common clinical features: they both affect women more than men, their diagnosis is based solely on clinical criteria, and some of the symptoms such as anxiety, aches and muscle tension, sleep disorders, and cognitive dysfunction occur in both diseases. For both conditions, an underlying dysregulation of the autonomic nervous system (ANS) has been proposed. OBJECTIVE: The aims of this study were to investigate ANS dysfunction in FM and GAD and compare them with controls. METHODS: Sympathetic skin response (SSR) from palm and sole and cross-sectional area (CSA) of bilateral vagus nerves (VN) were measured in 28 healthy controls, 21 FM patients, and 24 GAD patients. RESULTS: CSA of VN was significantly smaller in FM patients (right: 1.97 ± 0.74mm2, left: 1.75 ± 0.65 mm2) and GAD patients (right: 2.12 ± 0.97mm2, left: 1.71 ± 0.86 mm2) compared to controls (right: 3.21 ± 0.75 mm2, left: 2.65 ± 1.13 mm2, p < 0.001, but did not differ between the two patient groups. SSR parameters were similar between patients and controls. SSR latency correlated to clinical scales (FM Widespread Pain Index) in the FM group (r = 0.515, p = 0.02 and r = 0.447, p = 0.05) for the upper and lower limbs respectively, but no other correlation between clinical and neurophysiological parameters was identified. CONCLUSION: This study confirms similar ANS abnormalities in FM and GAD that fairly distinguish them from controls and support the hypothesis of a common pathophysiological substrate underlying both conditions.
Authors: Marina de Tommaso; Katia Ricci; Giuseppe Libro; Eleonora Vecchio; Marianna Delussi; Anna Montemurno; Giuseppe Lopalco; Florenzo Iannone Journal: Pain Res Treat Date: 2017-09-28