POS0738 BLUNTED CEREBRAL OXYGENATION DURING EXERCISE IN NON-NEUROPSYCHIATRIC SYSTEMIC LUPUS ERYTHEMATOSUS
Authors: N. Koletsos, K. Dipla, A. Triantafyllou, A. Lazaridis, N. Papadopoulos, A. Zafeiridis, S. Aslanidis, S. Douma, E. Gkaliagkousi
Journal: Annals of the Rheumatic Diseases (2021)

Background: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease affecting multiple organs, including the central nervous system. Subclinical brain lesions have been reported in SLE patients, even without overt neuropsychiatric manifestations (non-NPSLE). Studies using PET/MRI, examining structural or functional brain abnormalities in SLE, have been previously performed, either at rest or during a mental task (1–3). Exercise can be used to identify early alterations in brain oxygenation that might not detectable during resting conditions (4). Objectives: Our study aimed to examine possible differences in cerebral oxygenation during a handgrip exercise test between SLE patients without neuropsychiatric manifestations and age-matched controls. Methods: Fifty-two participants (26 non-NPSLE and 26 controls), following evaluation of handgrip strength, underwent a protocol involving a seated rest (baseline), a 3-min handgrip exercise (at 30% of maximal strength), and a 3-min recovery. Continuous-near-infrared-spectroscopy (NIRS) was used to monitor changes in cerebral-oxygenated hemoglobin (O2Hb), de-oxygenated (HHb) and total-hemoglobin (tHb). Beat-by-beat blood pressure (Finapres) was continuously monitored. Results: There were no differences between the two groups in age, body mass index, blood pressure, and smoking status. Median SLE duration was 7.5 (3.0 – 16.0) years. During exercise, cerebral -O2Hb increased in both groups; however, non-NPSLE exhibited a significantly lower increase in O2Hb vs. controls (average response:1.20±0.89 vs. 2.33±1.61μM, respectively, p&lt;0.005) and lower tHb responses (p&lt;0.05), with no differences in HHb. Conclusion: Our data show, for the first time, that SLE patients even without overt neuropsychiatric manifestations exhibit a blunted increase in cerebral-O2Hb during a submaximal exercise stimulus compared to age-matched controls. Examining brain oxygenation during a simple exercise task may assist in identifying patients with early alterations in cerebral function. References: [1]Mak A, Ren T, Fu EH yun, Cheak AA cia, Ho RCM. A Prospective Functional MRI Study for Executive Function in Patients with Systemic Lupus Erythematosus Without Neuropsychiatric Symptoms. Semin Arthritis Rheum. 2012;41(6):849–58. [2]Kozora E, Brown MS, Filley CM, Zhang L, Miller DE, West SG, et al. Memory impairment associated with neurometabolic abnormalities of the hippocampus in patients with non-neuropsychiatric systemic lupus erythematosus. Lupus. 2011;20(6):598–606. [3]Mackay M, Vo A, Tang CC, Small M, Anderson EW, Ploran EJ, et al. Metabolic and microstructural alterations in the SLE brain correlate with cognitive impairment. JCI Insight. 2019;4(1). [4]Triantafyllou GA, Dipla K, Triantafyllou A, Gkaliagkousi E, Douma S. Measurement and Changes in Cerebral Oxygenation and Blood Flow at Rest and During Exercise in Normotensive and Hypertensive Individuals. Vol. 22, Current Hypertension Reports. Springer; 2020. Disclosure of Interests: None declared