INVESTIGATING THE RELATIONSHIP BETWEEN ALTERED STRUCTURAL BRAIN METRICS (VOLUME, CORTICAL THICKNESS AND SURFACE AREA) AND COGNITIVE PERFORMANCE IN CHILDHOOD-ONSET SYSTEMIC LUPUS ERYTHEMATOSUS

O042 / #592 Topic: AS18 - Pediatric SLE ABSTRACT CONCURRENT SESSION 07: COGNITION IMPAIRMENT IN SLE – RECENT ADVANCEMENT AND EMERGING RESEARCH 23-05-2025 1:40 PM - 2:40 PM Background/Purpose Systemic lupus erythematosus (SLE) is a chronic, autoimmune, and inflammatory disease affecting nearly 3.41 million individuals worldwide. SLE is characterized by overproduction of autoantibodies causing inflammation in any organ system including the central nervous system (CNS), resulting in cognitive impairment. Childhood-onset SLE (cSLE) is associated with higher frequency of CNS involvement and cognitive difficulties. However, the neural underpinnings of these cognitive difficulties remain poorly understood. The objectives of this study are to identify differences in regional brain volume, cortical thickness and surface area in cSLE compared to age and sex-matched typically developing controls using structural magnetic resonance imaging (sMRI), and determine the association between brain structure and cognitive outcome in cSLE. Methods Participants (age 12-16 years), diagnosed with SLE meeting classification criteria and age and sex-matched healthy controls were recruited from January 2020–September 2023. Children completed a battery of neuropsychology tasks measuring attention (Conner’s Continuous Performance Test), working memory (Digit Span task; Weschler intelligence scale for Children: 5th Ed.), inhibition, cognitive flexibility and processing speed (Color-Word Interference task; Delis-Kaplan Executive Function System) and each score was standardized using age-based norms. T1-weighted images were also obtained for each subject and group differences in brain volume, cortical thickness and surface area were computed in FreeSurfer. Between group differences in cognitive performance were tested using two-tailed t-tests. Correlations between cognitive performance and structural measures were computed using Spearman’s rank correlation coefficient. Group differences in the proportion of cases meeting clinical criteria for cognitive difficulties (defined as scores ≥1.5 SD below the mean) were tested using χ 2 tests. All results are reported as significant at p <0.05. Results Thirty-two cSLE patients and 32 healthy controls participated. There were no differences in age, sex, or household income between groups. The mean disease duration for cSLE patients was 3.6years±2.8. On average, cSLE patients performed significantly worse on inhibition ( p =0.020) and processing speed tasks ( p =0.004). More cSLE patients than controls met clinical cut-offs for cognitive difficulties in the processing speed domain ( p =0.030). Neuroimaging results showed decreased volume, cortical thickness and surface area in the cSLE group (controls>cSLE) in several regions including the bilateral superior temporal gyrus (STG), left superior parietal gyrus, middle cingulate gyrus, right middle frontal gyrus. Decreased volume and surface area in the right STG were significantly correlated with worse cognitive performance. Decreased volume and cortical thickness in the anterior/posterior cingulate gyrus were significantly correlated with worse cognitive performance. Regions of increased surface area, volume and cortical thickness in cSLE>controls were also found and included the bilateral insula, right superior parietal gyrus, right inferior temporal gyrus, left inferior/superior frontal gyrus. Increased volume in the left inferior frontal gyrus was correlated with worse cognitive performance. Conclusions This study highlights the importance of neuropsychological assessment and utilizing advanced MRI methods to assess for CNS involvement in cSLE. Neuroimaging results revealed that specific areas of altered volume, cortical thickness and surface area were associated with decreased cognitive performance in cSLE. These results inform our understanding of the potential neural mechanisms underlying cognitive impairment in this population, which can be used to develop more targeted neuropsychological assessment and intervention approaches for the purposes of treatment planning.