Usefulness of Cube Copying in Evaluating Clinical Profiles of Patients with Parkinson Disease

Abstract

To clarify the relationship between the quantitatively assessed cube-copying test (CCT) and clinical profiles of cognitive and motor ability in Chinese patients with Parkinson disease (PD). We gave the Montreal Cognitive Assessment (MoCA), which includes the CCT, to evaluate the cognitive function of 102 outpatients with PD. We also gave the Unified Parkinson's Disease Rating Scale (UPDRS) II and III and the Hoehn-Yahr scale to evaluate the patients' motor function and disease severity, respectively. We used Maeshima's method for quantitative assessment of the CCT, and calculated CCT errors by adding incomplete connections and plane-drawing errors. We divided the patients into 2 groups based on normal (no errors) versus abnormal (≥1 errors) CCT scores. We found 34 patients with normal scores and 68 with abnormal scores. The 2 groups had significant differences in age of onset, MoCA score, UPDRS II and III scores, and cognitive deterioration rate. CCT errors correlated inversely with cognitive domains except for orientation. Executive function was most commonly affected in both groups. We found correlations between numbers of CCT errors and left-limb movement, fine hand movement, postural instability and gait disorders, UPDRS II and III scores, and cognitive and motor deterioration rates. The quantitatively assessed CCT may be useful in estimating cognitive and motor dysfunction in patients with PD, and in monitoring disease progression.