THE UTILITY OF VERBAL MEMORY TESTS AS SENSITIVE MARKERS FOR EARLY-STAGE ALZHEIMER’S DISEASE IN ELDERLY CHINESE AMERICANS

As the number of aging Chinese Americans continues to grow, it is important to develop measures for identifying individuals with Mild Cognitive Impairment (MCI) or mild Alzheimer's Disease (AD). This study tested the utility of two verbal memory tests: Philadelphia Verbal Learning Test (word list) and Logical Memory subtest of the Wechsler Memory Scale (story) as early markers for AD in elderly Chinese Americans. Data are from a pilot study at the Alzheimer's Disease Research Center at Icahn School of Medicine at Mount Sinai (ADRC ISMMS). All participants were ≥ 65 years old, primarily Chinese speaking (Mandarin or Cantonese), with adequate sensorimotor capacity to complete a three-hour dementia evaluation. This evaluation included a diagnostic interview, medical exam, cognitive testing, clinical assessments, and a research blood draw. Research diagnosis of normal, MCI, AD, and other types of dementia was made independently of the cognitive tests at a consensus conference led by a dementia expert physician and a neuropsychologist who conducted the interview, medical exam, and clinical assessments. Mild AD was defined by a global score of one on the Clinical Dementia Rating (CDR). Multivariable logistic regression models were used to assess the sensitivity of story and word list delayed recall for discriminating cognitive diagnosis of MCI/mild AD from normal control, adjusted for age, gender, and education. Receiver operating characteristic (ROC area, or AUC) was used to compare the predictive accuracy of the two memory tests. The sample included 64 normal and 15 MCI/mild AD (n=79). Normal controls were younger than the MCI/mild AD group (p=0.04). No significant differences were found in gender and education between the two groups. Story and word list delayed recalls both predicted cognitive diagnosis after adjustment for age, gender, and education. While word list (ROC=0.973) predicted cognitive diagnosis slightly better than story (ROC=0.913), the difference was not statistically significant in this small sample (p = 0.193). The effectiveness of verbal memory tests in discriminating individuals in the earliest stage of AD from healthy controls suggests that these measures are useful tools for early stage AD discrimination in elderly Chinese Americans.