Online First 2023-07-14

Introduction: Nervous system involvement is common in ANCA-associated vasculitides (AAV). While peripheral and central nervous system involvement are well described, it is still unclear how and to what extent the autonomic nervous system (ANS) is involved. Functional magnetic resonance imaging (fMRI) can provide information on both – structure and potential damage of the brain as well as the function of the selected brain centers. Objectives: The aim of this study was to investigate the ANS dysfunction in AAV patients and its correlation with fMRI results during the Valsalva maneuver. Patients and methods: 31 patients with AAV and 30 healthy controls were enrolled in the study. Each participant completed the COMPASS-31 questionnaire. Magnetic resonance imaging (MRI) was performed using a 3T scanner. Participants were asked to perform the Valsalva maneuver according to the fixed protocol using the device measuring the pressure value in the subjects’ airways. During the maneuver fMRI data were collected. The generalized least squares time series analysis and the region-of-interest (ROI) analysis were performed. Results: AAV patients had higher COMPASS-31 questionnaire median score (12.86 vs. 2.99; p<0.01), as compared to the control group. Structural MRI investigation did not reveal any significant differences between the groups. The brain centers involved in ANS function were detected during fMRI, however the analysis of ROI in patients and controls showed no differences. Conclusions: Patients with AAV have symptoms related to the ANS, but no differences in the functioning of the ANS brain centers have been demonstrated in fMRI study during the Valsalva maneuver.