[Prevalence of cognitive deterioration in people over 80-years-old: COGMANLLEU study]

We want to detect the prevalence of cognitive prevalence deterioration in the elderly population of 80-years-old or older, their grade of deterioration and the causal pathogenic entity.

a cross-sectional population study, including a first phase of screening and a second one of diagnosis confirmation.

a total of 877 elderly people of 80-years-old or older belonging to the basic health care area of Manlleu (Osona, Catalonia midlands). In the first phase, relatives and/or caregivers were interviewed, and the participating subjects underwent a set of tests. Those who obtained 24 points or less on the Mini-Mental State Examination (MMSE) and/or an equal Global Deterioration Scale (GDS) or over 3 were admitted to the second phase. During the second phase, a general and a neurological examination were performed, along with blood tests, cranial computed tomography scan and a neuropsychological study. DSM-IV criteria were used for dementia diagnosis, NINCDS-ADRA criteria for Alzheimer's disease (AD) and NINCS-AIREN for vascular dementia.

Half of the people over 80-years-old had cognitive deterioration. One-fourth had dementia. A total of 70.3% of these dementias corresponded to AD (47.2% AD without vascular lesions and 23.1% AD with vascular lesions) and 12% corresponded to vascular dementia. The percentage of other degenerative dementias was 17.6%. Age and gender were observed to be associated to dementia.

The prevalence of dementia in the COGMANLLEU study is similar to other European studies. AE is the most frequent dementia.