RT Journal Article SR Electronic T1 P40 Medial temporal lobe subregion volumes in systemic lupus erythematosus patients JF Lupus Science & Medicine JO Lupus Sci Med FD Lupus Foundation of America SP A68 OP A70 DO 10.1136/lupus-2024-el.94 VO 11 IS Suppl 1 A1 Najeeb, Zahra M A1 Jönsen, Andreas A1 Zervides, Kristoffer A1 Nilsson, Petra C A1 Bengtsson, Anders A1 Salomonsson, Tim A1 Kuchcinski, Gregory A1 Sundgren, Pia C A1 Wisse, Laura YR 2024 UL http://lupus.bmj.com/content/11/Suppl_1/A68.2.abstract AB Objective Systemic lupus erythematosus (SLE) often presents with neuropsychiatric (NP) symptoms, including cognitive impairment and depression. Past magnetic resonance imaging (MRI) research on hippocampal (HC) volumes, important for NP symptoms, in SLE patients yielded conflicting results and did not investigate other medial temporal lobe (MTL) regions.1 Our study aims to compare MTL subregional volumes in SLE patients to healthy individuals (HI) and explore the relationship between MTL subregional volume, cognition, and depression in SLE patients.Methods 70 SLE patients (mean age 36 years (range 18–51), mean disease duration 11.1 ± 8.0 years) and 25 HI (mean age 37.2 years (range 23–52)) underwent clinical evaluation, cognitive testing using CNS Vital Signs (CNS-VS), and 3 tesla MRI. T1-weighted MR images were analyzed using Automatic Segmentation of Hippocampal Subfields-T1 (figure 1). Analyses of Covariance were used to compare MTL subregion volumes between SLE patients and HI, and between NPSLE and non-NPSLE patients utilizing three classification models: the American College of Rheumatology definitions for NPSLE (42 NPSLE/ACR, 28 non-NPSLE), and the more stringent Systemic Lupus International Collaborating Clinics (SLICC) B (21 NPSLE/SLICC B, 49 non-SLICC B) and SLICC A models (15 NPSLE/SLICC A, 55 non-SLICC A). We explored the relation between MTL subregion volumes, cognitive, and depression scores (the self-reported Montgomery-Åsberg Depression Rating Scale, MADRS-S) in SLE patients using partial correlations. Covariates were age, intracranial volume, and education for cognitive analyses.Results NPSLE/ACR patients displayed significantly smaller volumes in the posterior HC, bilateral HC, and bilateral Brodman Area 35 (Br35) compared to non-NPSLE patients when applying the ACR case (p=0.04, 0.01, and 0.01 respectively). NPSLE/SLICC B showed significantly smaller left HC compared to non-SLICC B (p=0.03) (figure 2). No significant differences in MTL subregional volumes between SLE and HI were found. No significant correlations between MTL subregion volumes and cognitive or depression scores were observed.Conclusion NPSLE/ACR and NPSLE/SLICC B patients display significantly smaller volumes in some subregions of MTL, suggestive of a role of the MTL in NP symptoms in SLE. The lack of significant associations of MTL subregions with NP symptoms in SLE may be due to a lack of power.Acknowledgement This study has been supported by funding granted to Pia C Sundgren; Skåne University Research Funding, Funds from the Swedish Rheumatism Association, King Gustav V 80-years Foundation, and Alfred Östlund Foundation.Reference Cox JG, de Groot M, Cole JH, et al. A meta-analysis of structural MRI studies of the brain in systemic lupus erythematosus (SLE). Clinical rheumatology 2023;42(2):319–326.Abstract P40 Figure 1 Segmentation of medial temporal lobe subregions obtained by the Automated Segmentation of Hippocampal Subfields-T1 package. Each color corresponds to a different subregionAbstract P40 Figure 2 Box plots illustrating distribution of MTL subregion volumes between subgroups. The asterisk marks the presence of significant results