Background Systemic lupus erythematosus (SLE) is an inflammatory autoimmune disease characterized by frequent neuropsychiatric involvement, including cognitive impairment (CI), described in 3–80% of patients. In particular, deficits in attention, learning and recall, verbal and nonverbal fluency, language, visuospatial skills, executive functions and motor dexterity have been identified in SLE patients, suggesting a fronto-subcortical damage. The studies on CI in SLE are mostly cross-sectional, not allowing the evaluation of the modifications over-time. So far, only three longitudinal studies have been conducted on this topic, with a maximum follow-up of 5 years. Taken together, these studies suggested that CI seems a relatively consistent and stable finding in SLE.
Objectives We aimed at evaluating the modifications of CI in a 10 years prospective monocentric cohort study.
Methods We evaluated 43 SLE patients (M/F 5/38; mean age 45.7±10.1 years; mean disease duration 230.8±74.3 months) at baseline (T0) and after 10 years of follow-up (T1). Study protocol included data collection, evaluation of serum levels of anti-nuclear (ANA), anti-dsDNA, anti-cardiolipin (aCL), anti-β2glycoprotein I (aβ2GPI), anti-endothelial cell (AECA) antibodies and Lupus Anticoagulant (LA). SLEDAI-2K and SDI were used to assess disease activity and chronic damage, respectively. A test battery specifically designed to detect fronto-subcortical dysfunction across five domains (memory, attention, abstract reasoning, executive function and visuospatial function) was administered to all the patients. The same test battery was used at T0 and T1, performed by the same neurologist (MC). For each patient, the raw scores from each test were compared with published norms, then transformed into Z scores (deviation from normal mean), and finally summed in the Global Cognitive Dysfunction score (GCDs).
Results CI was identified in 20.9% of patients at T0 and in 13.9% at T1. This impairment was prevalently mild at T0 (55.5%) and mild or moderate at T1 (36.3% for both degrees). The assessment of CI modifications over-time demonstrated the improvement of CI in 50% of the patients, the stability in 40% and the worsening only in 10%. At T1, all the domains showed an improvement, with a significant difference from baseline for “executive function” (P=0.04) (Figure 1). Moreover, the presence of dyslipidemia (defined as elevated total or LDL cholesterol levels, or low levels of HDL cholesterol) was significantly associated with the involvement of any of the domains evaluated, except for “attention”. Finally, the worsening of visuospatial function resulted associated with LA (P=0.04).
Conclusions In the present prospective study, we evaluated for the first time the CI modifications in a cohort of SLE patients after a 10-years follow-up. After this long time, CI improved in the majority of patients; conversely, it worsened only in a small percentage. Furthermore, we observed an improvement in the overall cognitive functions, which reached a statistically significant difference for the executive functions. These results could suggest that an appropriate management of the disease during the follow-up was able to control SLE-related CI.
Disclosure of Interest None declared