OBJECTIVEIt is known that dementia is a multi-factorial disorder, but the etiological factors other than aging remain to be explored, hence we sought to investigate the risk factors of dementia and Alzheimer's disease (AD).

METHODSWe followed a community-based dementia-free cohort (n = 1301) aged 75 years and over in Stockholm, Sweden. Baseline data were obtained through a structured interview and extensive clinical examination, or by reviewing the inpatient register database. We used the DSM-III-R criteria to define dementia and AD cases.

RESULTSOver six years of a follow-up program,350 subjects were diagnosed as dementia, including 260 Alzheimer cases. Multiple Cox regression analysis suggested that older age,low education (< 8 years), cognitive impairment, functional disability (ADL > or = 1), low diastolic pressure (< 70 mm Hg), diabetes mellitus, coronary heart disease, and APOEepsilon4 allele were significantly or marginally associated with subsequent development of dementia and AD. Dementia was related also to stroke and atrial fibrillation. Antihypertensive drug use was associated with a lower risk of AD and dementia.

CONCLUSIONSOur study revealed that some sociodemographic features, cognitive and physical dysfunctions, vascular disorders, and genetic susceptibility were major risk factors for dementia and AD. Use of antihypertensive drugs might protect against the dementing disorders in a very old population.