Nidhi Desai1, Huma Nawaz2, NITAI MUKHOPADHYAY3, Kathryn Wyman-Chick4, Sarah Lageman2, Matthew Barrett2
1Virginia Commonwealth University School of Medicine, Richmond, VA, 2Department of Neurology, Virginia Commonwealth University, Richmond, VA, 3Department of Biostatistics, Virginia Commonwealth University, Richmond, VA, 4HealthPartners Neuroscience Center, St. Paul, MN
Objective:
Investigate the relationship between cognition and activities of daily living (ADLs) in Lewy body dementia (LBD).
Background:
Understanding the specific cognitive domains associated with ADL impairment in LBD may help identify patients who require additional support and who would benefit from targeted therapeutic interventions.
Design/Methods:
We analyzed neuropsychological test data for 207 LBD patients (including dementia with Lewy bodies (n=48) and Parkinson disease dementia (n=159)) in a clinical neuropsychological registry. All patients were evaluated for impairment in 8 ADLs. Patients were categorized as having either mild (<6 ADLs impaired), moderate (6 or 7 ADLs impaired), or severe (all 8 ADLs impaired). Neuropsychological test scores were compared between the ADL impairment groups using one-way ANOVA or Kruskal-Wallis H tests as appropriate.
Results:
Neuropsychological test performances differed significantly between the three groups (mild, moderate, and severe ADL impairment, respectively) on tests of global cognition [DRS-2 total scaled score: 5.5 (IQR=3-8) vs 6 (IQR=3-8) vs 3.5 (IQR=2-5), p=.0021]; speeded visuospatial processing [Trailmaking Part A T-score: 31 (IQR=19-40) vs 29 (IQR=21-36.5) vs 22 (IQR=18-29), p=.0012)]; speeded executive functioning [Trailmaking Part B T-score: 27 (IQR=16-34) vs 22 (IQR=18-39) vs 19 (IQR=16-23), p=.0057)]; and psychomotor processing speed [composite z-score: -1.9 (SD=1.1) vs -1.8 (SD=1.1) vs -2.9 (SD=1.2), p<.0001)]. Post-hoc comparisons revealed that the severely impaired ADL group performed significantly worse on these measures than the other ADL groups (p<.05). Impairments in driving and self-care were associated with worse performances on Trailmaking Part A, Trailmaking Part B, and psychomotor processing speed compared to patients without impairment in those activities (p<.05).
Conclusions:
Among patients with LBD, impairments in speeded tasks of visual processing and executive functioning are associated with impairment in ADLs, particularly driving and self-care. Processing speed performance may be useful in predicting limitations in ADLs in LBD.