Characterization of behavioral and psychological signs and symptoms in mild cognitive impairment and their prognostic value for Alzheimer's dementia

Intro: Mild cognitive impairment (MCI) is a clinical concept that identifies subjects who are in an intermediate cognitive state between normal aging and dementia. The aims of this study are: (1) Characterization of behavioral and psychological signs and symptoms (BPSD) in patients with MCI as compared to patients with dementia due to Alzheimer's disease (AD) and cognitively healthy older adults. (2) Evaluation of the prognostic role of these BPSD in MCI for the progression to AD.;Methods: The data of this study are from an ongoing prospective longitudinal study on BPSD in MCI and dementia. All subjects underwent in-depth BPSD assessment by means of a battery of scales: Middelheim Frontality Score (MFS), Behavioral Pathology in Alzheimer's Disease Rating Scale (Behave-AD), Cohen-Mansfield Agitation Inventory (CMAI), Cornell Scale for Depression in Dementia (CSDD) and Geriatric Depression Scale 30-questions (GDS-30).;Results: The BPSD profile of MCI patients was characterized as an intermediate state between normal aging and AD for the three main BPSD domains: agitation, mood and psychosis. The presence of these domains in AD led to associated symptoms: more severe frontal lobe symptoms (MFS), BPSD (Behave-AD), agitation (CMAI) and depressive (CSDD) symptoms. Also in MCI associated BPSD occurred, but less pronounced. Principal components analysis showed that in MCI, clustering of BPSD exists, resulting in a depression, psychosis and agitation syndrome. MCI is more dominated by a depression syndrome, while BPSD in AD is more subject to an agitation syndrome. So, the order of importance, as well as the structure of these syndromes, was different in MCI and AD. Cox proportional hazard analysis showed that the presence and severity of significant depressive symptoms in MCI were of prognostic value for the progression to AD. Moreover, also de severity of agitation, mainly verbally agitated behavior, and the presence of purposeless activities were predictors for the development of AD in MCI.;Conclusion: The cognitive and BPSD state of MCI is intermediate between normal aging and dementia. BPSD in MCI is dominated by a depression syndrome. Our longitudinal research concludes that depressive symptoms and agitation in MCI are of prognostic value for AD progression.