Cognitive Impairment Screening in the Clinic for Patients With SLE

Although patients with systemic lupus erythematosus (SLE) may report cognitive impairment, quantifying this and following the symptoms over time is challenging. However, there are some shorter assessments that have shown promise for use as initial screening tests for patients who might benefit from further neuropsychiatric testing and support, according to a study published in Lupus Science & Medicine.

Cognitive testing can be burdensome in the clinical setting, creating a need for rapid tools for screening. However, many of these rapid screening measures are designed for severe cognitive impairment or assess performance in single domains.

The authors explained that “previous studies have shown that dysfunction is widespread and heterogeneous across multiple cognitive function domains among individuals with SLE, with various levels of impairment in, for example, working and episodic memory, attention, processing speed, executive function and verbal fluency, among other domains.”

A clock-drawing test is one of the simple assessments used to determine potential cognitive impairment. Patients are first asked to draw a clock at a certain time, then shown the correct clock and asked to copy it.

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They administered 3 different cognitive performance assessments—the Trail Making Test B (TMTB); CLOX, a clock-drawing task; and the multidomain National Institutes of Health (NIH) Fluid Cognition Battery—as part of the Approaches to Positive, Patient-centered Experiences of Aging in Lupus study.

The NIH test was the primary measurement of cognitive function and TMITB and CLOX were included as short assessments used in the clinic. TMTB is used to screen for visual attention and task switching or cognitive flexibility. The test takes less than 5 minutes. CLOX takes approximately 5 minutes to complete and is used to screen for dementia and potential driving issues.

A total of 451 patients were included with 206 participating in person and 245 participating remotely. The mean age was 46 years. The majority (92%) were female, Black (82%), and non-Hispanic (94%) with at least some college education (77%). Nearly half (48%) were working at the time of the study. In addition, 27% reported moderate to severe symptoms of forgetfulness.

Based on TMTB, CLOX, and the NIH test, 65%, 55%, and 28% of patients, respectively, had potential impairment. There was overlap in potential impairment between TMTB and CLOX, although 58% of patients had impairment with only one of these assessments.

When a crude time cutoff of less than 273 seconds to complete the task was used for TMTB, only 3% of the cohort was considered potentially impaired. When that score was compared with norms across age and education groups, the potential impairment was 65%, which the researchers said suggests patients with SLE do not perform as well as peers on tasks involving executive functioning regardless of impairment.

There was also a wide variation in potential impairment for the CLOX test. While more than half of patients had a potential impairment for the first part of the test, which was drawing a clock without any visual cues, only 4% had impairment for the second part of the test, which asked them to copy a clock visual.

The authors noted that while CLOX and TMTB are both useful screening tools, “neither the CLOX or TMTB alone would be likely to capture multiple domains of performance and potential impairment.”

Factors associated with lower odds of potential cognitive impairment across all measurements were higher educational attainment, working status, and higher self-reported physical functioning and physical performance scores. For TMTB, younger age, Black race, higher disease activity and damage, and higher perceived stress score were associated with higher impairment odds. Neuropsychiatric damage was associated with higher odds of impairment for TMTB and CLOX.

One limitation of the study is that it was not designed as a validation study, which meant measures that could provide useful information were not included. Unmeasured or inadequately measured or factors may confound the results.

Overall, the authors determined CLOX and TMTB can be used as less burdensome screening tests, but the NIH test may allow for more targeted intervention due to the domain-specific information it provides.

“Future studies are needed to validate these measures in SLE, follow these measures over time within individuals, assess the clinical implications of impairment by these measures, and explore the outcomes of each of these performance measures and their change over time,” they concluded.

Reference

Plantinga L, Yazdany J, Bowling CB, et al. Comparison of cognitive performance measures in individuals with systemic lupus erythematosus. Lupus Sci Med. 2024;11(1):e001151. doi:10.1136/lupus-2024-001151