The need for an effective and reliable screening tool for cognitive impairment (CI) in patients with systemic lupus erythematosus (SLE) is important given the high prevalence of CI in that population. Researchers from the University of Toronto, Canada, recruited 98 consecutive adult patients with SLE to identify a screening test that is both cost-effective and easy to administer in an ambulatory setting, and published their results in the Journal of Rheumatology.
The objectives of the analysis were: (1) to determine the prevalence of CI in patients with SLE per evaluation by the Montreal Cognitive Assessment (MoCA), Mini Mental State Examination (MMSE), Hopkins Verbal Learning Test–Revised (HVLT-R), and Perceived Deficits Questionnaire 5-Item (PDQ-5); and (2) to define the association between patients’ demographic, psychosocial, and clinical findings and their cognitive function.
The researchers administered the HVLT-R, MoCA, and MMSE to patients to assess the respective sensitivity/specificity, positive predictive value (PPV), negative predictive value (NPV), and positive likelihood ratio (LR+) of MoCA/MMSE compared with HVLT-R. All participants completed a test on intellectual ability and questionnaires regarding anxiety, depression, and perceived cognitive deficits.
Of the patients investigated, 48% had CI per the results of the MoCA and 31% per the
HVLT-R. Sensitivity was higher for the MoCA compared with the MMSE (73% vs 27%, respectively), although the MMSE was more specific than the MoCA (90% vs 63%, respectively). PPV and LR+ were similar in MoCA and MMSE (PPV: 47% and 53%, respectively; LR+: 2.0 and 2.6, respectively). In contrast, NPV was higher in MoCA than in MMSE (84% vs 74%, respectively).
PDQ-5 was predictive of objective CI (HVLT-R: sensitivity 100%; specificity 89%). CI was significantly associated with depression on univariate analysis (P =.01); this association did not persist on multivariate analysis. Longer SLE disease duration (odds ratio [OR], 0.94; P =.02) and more advanced educational background (OR, 0.81; P =.02) remained significant on multivariate analysis. Every 1-year increase in the years of a participant’s education reduced the probability of CI by 19%.
The researchers concluded that CI is highly prevalent in the SLE population, and MoCA may be useful in the clinical setting to screen such patients for CI. Additional studies are warranted to confirm the validity of MoCA in this setting.
Nantes SG, Su J, Dhaliwal A, Colosimo K, Touma Z. Performance of screening tests for cognitive impairment in systemic lupus erythematosus [published online September 1, 2017]. J Rheumatol. doi:10.3899/jrheum.161125