BACKGROUND: The discrimination of dementia and depression remains an issue of debate as they often co-exist in late life. Various neuroimaging techniques have been used in an attempt to differentiate between the two entities. Visual rating seems to offer a quick and reliable tool for diagnosis. We performed a retrospective study to assess the potential role of the visual rating method to assist in the differential diagnosis of AD versus depression.

METHODS: A sample of memory clinic patients fulfilling clinical criteria of either AD (n = 113) or depression (n = 139) was recruited. Depressive symptoms were defined as a score of 10 or higher on the GDS. Patients with AD were at a mild stage of disease (MMSE>23). Based on previous studies, 13 regions of interest were selected in both hemispheres, including mainly frontal, temporal and hippocampal areas. The regions were validated by two raters by using a visual scale with four stages of atrophy (0 to 4). Data were calculated using the binary logistic regression model.

RESULTS: Based on visual assessment, patients with AD showed more atrophy in the right anterior cingulate cortex and in temporal, limbic and hippocampal regions in comparison to patients with depression.

CONCLUSION: Visual rating scales offer a useful method to distinguish between AD and deperession in clinical practice.