Abstract

Background Although Alzheimer disease (AD) is clinically defined by progressive memory decline, neuropsychiatric symptoms (NPS) are present from very early stages, being apathy the most common NPS. Disease evolution is characterized by progressive impairment in activities of daily living (ADL) from very mild impairment in mild cognitive impairment (MCI) to total dependency in the severe states. In addition, ADL could be divided in basic (selfcare), instrumental (household, shopping, travel, communication), and advances ones (work, use of technology) being the last the first affected in symptomatic AD. Objectives 1. Analyze the factors related with ADL impairment in at different stages of AD: very mild o MCI, and mild to moderate AD. 2. Analyse the factors related with different types of ADL: basic, instrumental and advanced. Methods A convenience sample of 88 AD patients was graduated in very mild to mild to moderate severity using the clinical dementia rating (CDR) (CDR 0,5, n=21); (CDR 1 =44 & CDR 2 n= 23). They were assessed with measures of global cognition, executive functions, episodic memory; NPS, apathy, depression and functionality (technology-activities of daily living questionnaire (T-ADLQ)). Lineal regression models were done to assess the better predictors for functional impairment in the global group and in the mild and moderate severity patients separately. Results Functional impairment was 35±18 % in the total sample, increasing it proportion according to disease severity (CDR 0,5&1=29% CDR2&3=46%). At least one behavioral symptom was present in 87% of AD patients, depressive symptoms were present in about half of the patients. Apathy (defined as AES-i >41) was present in 44 % of AD patients. Significant predictors of global functional impairment were education, NPS, global cognition and apathy; in mild AD patient’s apathy was the best predictor. Conclusions Apathy alone explained one third of functional impairment in AD patients, been especially important in the mild severity group, it was even more relevant than measures of episodic memory, executive functions or depression. These results remark the importance of apathy evaluation to fully understand AD patient’s behavior. Funded by FONDECYT 1140423, REDES 150134, Proyecto Anillo ACT1403.