Neuropsychiatric symptoms of Alzheimer's disease differ in Chinese and American patients

The prevalence of Alzheimer's disease is similar across ethnic groups. To our knowledge, no comparison of behavioral symptoms has been addressed.

This cross-sectional, retrospective, descriptive study compares neuropsychiatric symptoms of Chinese subjects with Alzheimer's disease (AD) at tertiary care centers in Taiwan and Hong Kong against Caucasian subjects in Los Angeles, California. We compared the frequency and severity of symptoms and caregiver responses to neuropsychiatric symptoms of AD using the Neuropsychiatric Inventory (NPI). We hypothesized that Chinese patients do not seek care unless they have high severity of neuropsychiatric symptoms and that Caucasian Americans do not wait for behavioral disturbances to develop before coming to medical attention.

The Caucasian sample had the highest mean educational level and mildest Clinical Dementia Rating (CDR) scale distributions of all four groups. Older age and lower educational levels contributed to higher CDR scale scores, which in turn correlated with higher total NPI scores. Only one of the Chinese samples had a higher frequency of severe neuropsychiatric symptoms than the Caucasian sample. Chinese caregivers reported anxiety and delusions more frequently (58.1%) than Caucasians (37.3% and 39.6%; chi(2), p < 0.01 and p < 0.05, respectively). Caucasians reported appetite changes (47.3%) and apathy (59.2%) more frequently than the Chinese samples (chi(2), p < 0.05 and p < 0.01, respectively). Caregivers at all four centers were distressed by behaviors qualified as severe.

We found support for our hypothesis, in that Chinese subjects presented during a more severe stage of dementia than American subjects, but the delay in seeking care could not be correlated with significant differences in neuropsychiatric profiles of the demented subjects. Other barriers to dementia care warrant investigation.