Assessing grey matter structural alterations in systemic lupus erythematosus using synthetic MRI

Objectives To assess brain grey matter alterations in patients with SLE and their correlation with neuropsychological testing using synthetic MRI (SyMRI). Methods This prospective study enrolled patients with SLE and age, gender and education-matched healthy controls (HC). Study assessments included brain MRI using SyMRI and neuropsychological tests: Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Digit Span Test, Self-Rating Anxiety Scale and Self-Rating Depression Scale (SDS). SyMRI post-processing and Automated Anatomical Labeling were used for grey matter mapping. Correlation analysis was performed to assess the relationship between brain grey matter structural alterations and neuropsychological testing. Results 77 patients with SLE (57 non-neuropsychiatric SLE (non-NPSLE), 20 NPSLE) and 29 HC participants were enrolled. Patients with SLE showed reduced grey matter volume compared with HC (p<0.05). The NPSLE group exhibited more extensive increases in longitudinal (T1) and transverse (T2) relaxation times in grey matter than the non-NPSLE group (p<0.001). Proton density values were lower in patients with SLE (p<0.001). Lower brain parenchymal volume correlated with higher SLE Disease Activity Index (p<0.05). Lower MMSE/MoCA scores correlated with increased T1/T2 in the left medial cingulate and paracingulate gyri (p<0.05). Higher SDS scores correlated with increased T1/T2 in the left calcarine fissure and surrounding cortex (p<0.05). These changes were also linked to disease markers (C3, C4, immunoglobulin M, erythrocyte sedimentation rate) (p<0.05). Conclusions Grey matter alterations in patients with SLE correlate with cognitive impairment, depression and disease activity.