Associations between visual hallucinations and impaired visuo-spatial abilities in dementia with Lewy bodies.

Objectives

In dementia with Lewy bodies (DLB) recurrent visual hallucinations (VH) often coexist or occur consecutively to impaired visual perception. Since in-depth neuropsychological testing is time-consuming, and therefore, not routinely performed in clinical settings, we aimed to explore whether standard cognitive screening tests may be helpful to alert a clinician to the presence of VH in DLB by exploring association between visuo-spatial dysfunction and VH. Method: The clock drawing, cube, and pentagons copying items from Montreal Cognitive Assessment and Mini-Mental State Exam and nonmotor Hooper visual organization test (HVOT) have been scored in DLB patients with and without VH using traditional and extended scoring methods.

Results

Forty-five of 69 (65%) DLB patients were VH-positive (VH+). VH+ patients performed worse on the clock drawing (8.8/16 vs. 11.9/16, p = .016) with a higher rate of misrepresentation of time (69% vs. 29%, p = .002) and numbers (53% vs. 25%, p = .024). Likewise, VH+ patients performed worse on the HVOT (13.3/30 vs. 15.7/30, p = .009) having more isolated (6.2/30 vs. 4.4/30, p = .012) types of responses compared to VH- patients. Both groups had similar copying ability (p > .05). The VH discriminative accuracy of the clock drawing was comparable to that of the more elaborate test of visual perception, the HVOT.

Conclusions

In DLB impaired drawing and visual organization, but not copying ability is associated with the presence of VH. The simple clock drawing test can be helpful to alert a clinician to the possibility of VH in DLB. (PsycInfo Database Record (c) 2021 APA, all rights reserved).