Performance of the Pentagon Drawing test for the screening of older adults with Alzheimer's dementia

ABSTRACT The Pentagon Drawing Test (PDT) is a common cognitive screening test. Objective: The aim of this study was to evaluate performance properties of a specific PDT scoring scale in older adults with Alzheimer's disease (AD) and healthy controls. Methods: A cross-sectional study of 390 elderly patients, aged 60 years or older with at least two years of education was conducted. All participants completed clinical and neuropsychological evaluations, including the Cambridge Cognitive Examination, the Mini-Mental State Examination (MMSE), and the Clock Drawing Test. All PDT were blindly scored with the scale of Bourke et al. Results: PDT analyses of the binary score on the MMSE (0 or 1 point) did not discriminate AD from controls (p = 0.839). However, when PDT was analyzed using the Bourke et al. scale, the two groups could be distinguished (p <0.001). PDT was not affected by education, showed sensitivity of 85.5% and specificity of 66.9%, discriminated different clinical stages of dementia, and correlated with the other cognitive tests (p <0.001). A 1-point difference on the Bourke et al. scale was associated with an odds ratio of 3.46 for AD. Conclusion: PDT can be used as a cognitive screen for suspected cases of dementia, especially AD, irrespective of educational level.

摘要 五边形绘画测试（Pentagon Drawing Test, PDT）是一种常用的认知筛查工具。研究目的：本研究旨在评估特定PDT评分量表在阿尔茨海默病（Alzheimer's disease, AD）老年患者与健康对照人群中的表现特性。研究方法：本研究为横断面研究，共纳入390名60岁及以上、受教育年限至少2年的老年受试者。所有受试者均完成临床及神经心理学评估，包括剑桥认知检查、简易精神状态检查（Mini-Mental State Examination, MMSE）以及钟形绘画测试。所有PDT样本均采用Bourke等人开发的量表进行盲法评分。研究结果：针对简易精神状态检查（MMSE）的二进制评分（0分或1分）开展的PDT分析无法区分阿尔茨海默病患者与健康对照人群（p=0.839）。然而，当采用Bourke等人的量表对PDT结果进行分析时，两组受试者可被有效区分（p<0.001）。PDT评分不受受教育程度影响，其灵敏度为85.5%、特异度为66.9%，可区分不同临床分期的痴呆，并与其他认知测试结果呈显著相关（p<0.001）。Bourke量表上每相差1分，阿尔茨海默病发病的优势比为3.46。研究结论：五边形绘画测试可作为疑似痴呆（尤其是阿尔茨海默病）患者的认知筛查工具，且不受受教育程度的限制。