SAN DIEGO—The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) may help neurologists assess cognitive deficits in patients with Huntington’s disease, according to a study presented at the 65th Annual Meeting of the American Academy of Neurology. Results of the RBANS correlate well with those of other common cognitive and functional measures for patients with Huntington’s disease and persons at risk for the disorder. The test may be less useful, however, in distinguishing between at-risk individuals and healthy individuals, except when the at-risk individuals are estimated to be within 10 years of disease onset.
Comparing RBANS and Other Common Cognitive Tests
Elizabeth Breen, research assistant at Neurosciences University of California in San Diego, and colleagues administered the RBANS to 25 patients with Huntington’s disease, 28 patients at risk for the disease, and 19 controls. The participants also underwent the Mini Mental State Examination, the Montreal Cognitive Assessment, the Mattis Dementia Rating Scale, and the Total Functional Capacity section of the Unified Huntington’s Disease Rating Scale.
The researchers compared RBANS scores for each study group using a one-way analysis of variance and multiple comparisons tests. Ms. Breen also used Pearson’s r to examine the correlation between RBANS scores and the other cognitive and functional measures.
RBANS Results Distinguished Controls From Patients With Huntington’s Disease
The study participants were well matched with regard to age and education. At-risk subjects and controls had similar scores on the cognitive measures, but scores for patients with Huntington’s disease indicated cognitive impairment. At-risk subjects and controls achieved perfect scores on functional measures, and the Huntington’s group’s average score was 9, which indicates mild functional impairment. Patients with Huntington’s disease also exhibited more motor symptoms than did at-risk individuals.
The researchers found significant differences in mean RBANS total scores and in each of the subscales between patients with Huntington’s disease and controls. The effect sizes were also large. Patients with Huntington’s disease “were impaired and had lower scores, [but] were nowhere near the bottom of the scale,” said Ms. Breen. “On the other hand, the controls didn’t really approach a maximum score in any category. This suggests that the RBANS doesn’t show floor or ceiling effects,” she added.
A comparison of mean RBANS scores for patients with Huntington’s disease and at-risk individuals revealed significant differences in total score and in each of the subscales except the visuospatial section. Again, the effect sizes were large.
No significant differences in RBANS scores were apparent, however, between at-risk subjects and controls. When the researchers compared at-risk patients who were within 10 years of disease onset—according to the Langbehn equation—to controls, they found significant differences in total RBANS score, visuospatial ability, and delayed memory. Effect sizes in those categories were large. “This [result] suggests that as patients get closer to conversion to Huntington’s disease, the RBANS might be sensitive to some of the cognitive changes that begin to appear,” said Ms. Breen.
—Erik Greb
Senior Associate Editor
Suggested Reading
Beglinger LJ, Duff K, Allison J, et al. Cognitive change in patients with Huntington disease on the Repeatable Battery for the Assessment of Neuropsychological Status. J Clin Exp Neuropsychol. 2010;32(6):573-578.
Mickes L, Jacobson M, Peavy G, et al. A comparison of two brief screening measures of cognitive impairment in Huntington’s disease. Mov Disord. 2010;25(13):2229-2233.