THE COPY OF PENTAGONS IN THE DIAGNOSIS OF PRODROMAL DEMENTIA WITH LEWY BODIES

Abstract

Prodromal Dementia with Lewy Bodies (PDLB) involves the period between the onset of the earliest symptoms (cognitive and noncognitive) and the development of dementia. Visuospatial deficits are present in the early stages of DLB according to the recent update of the diagnostic criteria. The objective of the study was to determine the usefulness of the copy of pentagons as a screening tool. Subjects were stratified into four groups: Patients with PDLB, Minor Neurocognitive Disorder (Minor NCD), Major Neurocognitive Disorder (Major NCD) and control cases. All were evaluated with pentagon test within an extensive neuropsychological evaluation, including the ALBA Screening Instrument (ASI, a screening tool designed to Lewy Body Dementia). The sample consisted of 359 subjects: 53 cases with PDLB, 140 with Minor NCD, 75 with Major NCD, and 91 control cases. The sensitivity obtained in the test is 45.3% and the specificity of 80.7% for the detection of PDLB when considering all groups. The percentage of patients with PDLB who performed the test correctly was significantly lower than that found in the control group and the group of patients with Minor NCD. However, no significant differences were found between patients with PDLB and Major NCD. The copy of Pentagons presents a low sensitivity and high specificity for which it would not be possible to consider it as a useful tool for the detection of patients with PDLB. However, it would be a simple tool to differentiate PDLB from other disorders suggesting that future studies for early screening should focus on visuospatial abilities.