Memory and Executive Dysfunction Predict Complex Activities of Daily Living Impairment in Amnestic Multi-Domain Mild Cognitive Impairment.

BACKGROUND: Specific cognitive alterations could be one of the predictors that lead to the complex activities of daily living (CADL) impairment in mild cognitive impairment (MCI) and, hence, help to explain the continuum between MCI and dementia. OBJECTIVE: We aimed to reevaluate the existing uncertainty regarding the impact of memory and executive functions on CADL in patients with MCI. METHODS: Caregivers of 161 patients with amnestic multi-domain MCI and of 150 patients with incipient Alzheimer's disease as well as 100 age-, sex-, and education-matched controls, completed the Interview for Deterioration in Daily Living Activities in Dementia, a suitable instrument for the description and discrimination of CADL. In addition, all patients and controls were assessed with a neuropsychological battery to measure explicit memory and executive functions performance. RESULTS: Multiple regression analyses showed that in the group of patients with amnestic multi-domain MCI, 67.4% of the variability of the CADL impairment was explained by worse performance on executive functions tests (p < 0.0001) and 41.8% by different explicit memory components impairment (p < 0.0001). Further, in patients with incipient AD, 44.0% of the variability of CADL impairment was explained by worse performance on executive functions tests (p < 0.0001) and 39.9% by different explicit memory components worsening (p < 0.0001). CONCLUSIONS: Memory and executive functions alterations impact similarly on the CADL in both amnestic multi-domain MCI and incipient Alzheimer's disease. Given the continuum that exists between both conditions, we conclude that CADL impairment may be an important early step in the evolution towards Alzheimer's disease from amnestic multi-domain MCI.

Neurological Disorders in Central Spain, Second Survey: Feasibility Pilot Observational Study.

BACKGROUND: The Neurological Disorders in Central Spain, second survey (NEDICES-2) is a population-based, closed-cohort study that will include over 8000 subjects aged ≥55 years. It will also include a biobank. OBJECTIVE: The objective of this study was to evaluate all major aspects of the NEDICES-2 (methods, database, screening instruments, and questionnaires, as well as interexpert rating of the neurological diagnoses) in each one of the planned areas (all of them in central Spain) and to test the possibility of obtaining biological samples from each participant. METHODS: A selection of patients and participants of the planned NEDICES-2 underwent face-to-face interviews including a comprehensive questionnaire on demographics, current medications, medical conditions, and lifestyle habits. Biological samples (blood, saliva, urine, and hair) were also obtained. Furthermore, every participant was examined by a neurologist. RESULTS: In this pilot study, 567 study participants were enrolled (196 from hospitals and 371 from primary care physician lists). Of these 567, 310 completed all study procedures (questionnaires and the neurological evaluation). The study was time-consuming for several primary care physicians. Hence, a few primary care physicians from some areas refused to participate, which led to a reconfiguration of study areas. In addition, the central biobank needed to be supplemented by the biobanks of local Spanish National Health System hospitals. CONCLUSIONS: Population-based epidemiological surveys, such as the NEDICES-2, require a pilot study to evaluate the feasibility of all aspects of a future field study (population selection, methods and instruments to be used, neurological diagnosis agreement, and data collection).