Interview for Deterioration in Daily Living Activities in Dementia: construct and concurrent validity in patients with mild to moderate dementia.

BACKGROUND: The purpose of the study was to translate the Interview for Deterioration in Daily Living Activities in Dementia (IDDD) into German and to evaluate the construct and concurrent validity in people with mild to moderate dementia. METHODS: IDDD data of two pooled samples (n = 301) were analyzed regarding ceiling and bottom effects, internal consistency, factor reliability and correlations with corresponding scales on cognition and activities of daily living. RESULTS: We found minimal bottom (< 5%) and ceiling (≤ 2%) effects, good internal consistency (Cronbach's α > 0.7) and moderate to good factor reliability (0.66-0.87). Low correlations with cognition (Pearson coefficient: < 0.17) confirmed the differences between cognitive testing and activities of daily living (ADL). Minor correlations with other ADL scores (r < 0.2) indicated that different scores cover a different range of ADLs. The original two factor model could not be confirmed. A suggested four factor model distinguishing initiative and performance of basic and instrumental ADL demonstrated better indices of fit and higher correlations with corresponding scales. CONCLUSION: A four factor model of the IDDD can be used in dementia research for assessing initiative in and performance of basic and household activities of daily living. The findings suggest that ADL scales correlate only poorly and that further development of the IDDD is needed to cover a broader range of ADLs.

Cardiovascular risk and hippocampal thickness in Alzheimer's disease.

Cardiovascular risk factors influence onset and progression of Alzheimer's disease. Among cognitively healthy people, changes in brain structure and function associated with high blood pressure, diabetes, or other vascular risks suggest differential regional susceptibility to neuronal damage. In patients with Alzheimer's disease, hippocampal and medial temporal lobe atrophy indicate early neuronal loss preferentially in key areas for learning and memory. We wanted to investigate whether this regional cortical thinning would be modulated by cardiovascular risk factors. We utilized high-resolution magnetic resonance imaging and a cortical unfolding technique to determine the cortical thickness of medial temporal subregions in 30 patients with Alzheimer's disease. Cardiovascular risk was assessed using a sex-specific multivariable risk score. Greater cardiovascular risk was associated with cortical thinning in the hippocampus CA2/3/dentate gyrus area but not other hippocampal and medial temporal subregions. APOE genotype, a family history of Alzheimer's disease, and age did not influence cortical thickness. Alzheimer's disease-related atrophy could mask the influence of genetic risk factors or age on regional cortical thickness in medial temporal lobe regions, whereas the impact of vascular risk factors remains detectable. This highlights the importance of cardiovascular disease prevention and treatment in patients with Alzheimer's disease.