Noncognitive symptoms in Alzheimer's disease. A study of 150 community-dwelling patients using a questionnaire completed by the caregiver.

We studied the noncognitive symptoms in 150 community-dwelling Alzheimer's patients using a questionnaire completed by the caregiver, the Echelle Psyc hopathologique de la Demence de Type Alzheimer, EPDTA (Psychopathologic Sca le of Dementia of Alzheimer Type). EPDTA is a 44-item questionnaire derived from the BEHAVE-AD and the Depressive Mood Scale, covering many aspects of the behavior, affective and psychiatric disturbances. Each item is rated f rom a (never observed) to 6 (most of the time). Frequency (percentage of sy mptom present) and severity (mean score when the symptom was present) were assessed for each item. The cognitive status and severity of the disease we re assessed by the MMSE and two scales completed by the caregiver assessing the Activities of Daily Living scale (ADL) and the Cognitive Difficulties Scale (CDS). Noncognitive symptoms were present in all patients but remained moderate in severity. A principal component analysis of the 33 items exploring the aff ective disturbances showed seven clinically relevant factors: apathy, anxie ty, anosognosia-irritability, euphoria, dysphoria, emotional incontinence a nd agitation. The most frequent noncognitive symptoms were the affective di sturbances, especially apathy, and the sexual behavioural disturbances. No correlation were found between the overall severity of behavioural disturba nces and cognitive status, duration of the disease nor demographic variable s. However, a slight negative correlation was found between scores on apath y and on the MMSE. A second evaluation was performed in 59 patients after a mean follow-up of 18,2 months. The patients showed a progression of the disease evidenced by the scores on the MMSE, ADL and CDS scales. However, the frequency and seve rity of the noncognitive symptoms remained identical except for eating diso rders, psychotic symptoms and agitation which were more frequent at the sec ond examination and negatively correlated with the MMSE score. Most patients showed affective disturbances and scored high for apathy and anxiety-emotional incontinence dimensions. Like in a previous study, we fou nd a double dissociation between these two dimensions in some patients, sug gesting that they depend from different mechanisms. Agressivity, mostly ver bal, was found in three quarters of the patients and was correlated to apat hy, anosognosia and psychotic symptoms. Conclusion: The relationship between noncognitive manifestations and cognit ive deficits in AD is not clear, suggesting that they depend from different biological and psychological mechanisms. Various dimensions may be describ ed in the behavioural disturbances but their relationship with hypothetical biological mechanisms remains difficult Our study stresses the importance of apathy, which was corelated with vario us noncognitive psychobehavioral manifestations in AD patients.