Photo Credit: Nathan Devery

A new screening instrument can identify cognitive impairment in patients with ALS both within and beyond the established FTD spectrum.

A new screening instrument called the Complementary Cognitive ALS Screen (C-CAS) can identify cognitive impairments in patients with amyotrophic lateral sclerosis (ALS) both within and beyond the established frontotemporal dementia (FTD) spectrum, according to a study in the Journal of Neurology.

“Through a cross-sectional, prospective case–control study involving 314 controls and 184 ALS patients, we identified impairments in cognitive functions not detected by previous screening tools,” wrote corresponding author Henk-Jan Westeneng, MD, and coauthors from the UMC Utrecht Brain Center at University Medical Center Utrecht, Utrecht, the Netherlands.

The C-CAS was designed to complement the Edinburgh Cognitive and Behavioural ALS Screen (ECAS) and, through 12 items, gauges impairments in 6 domains: social cognition, inhibition, cognitive flexibility, visuoconstruction, incidental nonverbal memory, and body orientation.

“The practical online tool provides C-CAS item-specific scores and sum score results and classifies them as normal or impaired based on normative data collected in control,” researchers wrote.

The study tested the C-CAS with 314 controls recruited from a population-based study and 184 patients with ALS. Researchers determined that the C-CAS was feasible and well-tolerated. The average time to complete the C-CAS was between 15 and 20 minutes.

C-CAS Plus ECAS Enables Identification of Different ALS Phenotypes

According to the study, patients with ALS performed worse across all items compared with controls. Among patients with ALS, 16% had impairments in social cognition, 14% had impairments in inhibition, and 12% had impairments in cognitive flexibility, all of which are within the FTD spectrum. Overlap with EACS impairments was minimal.

“Beyond the FTD spectrum, impairments were found in visuoconstruction, incidental non-verbal memory, and body orientation (13% each),” researchers reported, “with minimal overlap with ECAS memory or visuospatial impairments.”

C-CAS sum scores were abnormal, defined as below the 5^th percentile in controls, for 24% of patients with ALS, including 15% of patients with normal ECAS total scores. Meanwhile, the ECAS identified cognitive impairments in 5% of patients with normal C-CAS sum scores.

“By employing the C-CAS alongside the ECAS, we can systematically screen a larger portion of the cognitive heterogeneity in ALS, enabling the identification of different ALS phenotypes,” researchers wrote. “This standardized approach enhances personalized patient care and contributes to stratification in clinical trials and the development of targeted interventions.”