ABSTRACT NUMBER: ESOC2026A798 EFFECTS OF AUTONOMIC DYSFUNCTION INDUCED BY SLEEP APNEA EVENTS ON DEEP BRAIN LESIONS, PLASMA BIOMARKERS, AND COGNITIVE FUNCTION IN CEREBRAL SMALL VESSEL DISEASE

Abstract Background and aims Obstructive sleep apnea and autonomic dysfunction are intimately linked with cerebral small vessel disease (CSVD). Heart rate fragmentation (HRF) serves as a quantitative marker of cardiac autonomic dysfunction and demonstrates correlations with both sleep apnea severity and cognitive decline. This study aimed to explore the associations between sleep apnea parameters, autonomic function, CSVD burden, plasma neurobiomarkers, and cognitive function, and to clarify the predictive value of multimodal indicators for cognitive impairment. Methods A total of 116 patients with CSVD were enrolled. Polysomnography was used to measure sleep parameters and the HRF indicator, percentage of inflection points (PIP). Magnetic resonance imaging based CSVD features were evaluated using a visual rating scale. Plasma concentrations of P-tau217 and NfL were measured. Cognitive function was assessed using the Montreal Cognitive Assessment. Structural equation modeling (SEM) was employed to explore the pathways among apnea-hypopnea index (AHI), PIP, P-tau217, and NfL. Results AHI was positively correlated with both PIP and deep brain lesions (both P<0.05). PIP demonstrated positive correlations with deep brain lesions, P-tau217, and NfL levels (all P<0.05). Multimodal indicators significantly improved diagnostic accuracy for cognitive impairment (AUC=0.835, 95% CI: 0.794–0.911). SEM revealed that PIP mediated the effect of AHI on deep CSVD lesions and indirectly influenced P-tau217 and NfL levels through deep lesion severity. Conclusions This study reveals the potential associations among obstructive sleep apnea, autonomic nervous function and CSVD. The adoption of a multimodal assessment strategy holds significant clinical utility for the early identification and timely intervention in the diagnosis and management of CSVD. Conflict of interest Along Hou, Cheng Wenbin, Xiong Xinli, Chen Xiaohan, Sun Wenjing, Xiong Ran, Xu Wei, Shen Lei, You Yin and Li Gang. nothing to disclose