Prevalence of cognitive impairment using the Montreal Cognitive Assessment questionnaire among patients with systemic lupus erythematosus: a cross-sectional study at two tertiary centres in Malaysia

INTRODUCTION: Cognitive impairment is a common neuropsychiatric manifestation of systemic lupus erythematosus (SLE). However, it is not routinely assessed for despite its high prevalence and significant disease burden.

AIMS: This study aimed to determine the prevalence of mild cognitive impairment (MCI) using the Montreal Cognitive Assessment (MoCA) and its associated factors among patients diagnosed with SLE in Malaysia.

METHODS: A total of 200 SLE patients were recruited prospectively from the outpatient clinics of two tertiary hospitals in Malaysia. Standardized clinical interview was utilized to obtain information on socio-demographic characteristics. All patients were then assessed using the MoCA questionnaire for presence of cognitive impairment; the Patient Health Questionnaire 9 (PHQ-9) for presence of depressive symptoms; and the Wong-Baker Faces Pain Scale (WBFPS) for severity of pain. The evaluation of disease activity and severity were performed by the treating rheumatologists and nephrologists using the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and Systemic Lupus International Collaborating Clinics Damage Index (SLICC DI).

RESULTS: The prevalence of MCI was 35%. The significant associated factors from the bivariate analysis were male gender (p = 0.04), educational level (p = 0.00), WBFPS score (p = 0.035) and anticardiolipin IgM (p = 0.01). Further analysis using logistic regression model found that male gender (OR = 7.43, 95% confidence interval 1.06-52.06, p = 0.04), lower educational level (OR = 4.4, 95% confidence interval 1.47-13.21, p = 0.01) and presence of anticardiolipin IgM (OR = 6.81, 95% confidence interval 1.45-32.01, p = 0.031) were associated with impaired MoCA scores. Also, increasing pain scores increased the risk of patients being affected by cognitive impairment.

CONCLUSION: Over one-third of patients with SLE in our cohort were found to have MCI. Risk factors included male gender, lower educational level, higher pain score and presence of anticardiolipin IgM. Physicians are encouraged to perform routine screening to detect cognitive dysfunction in patients with SLE in their clinical practice as part of a more comprehensive management.