The prevalence of dementia and cognitive deficit in a rural population of 2442 residents in northern Italy. A door-to-door survey.

A population study to estimate the prevalence of dementia was carried out amongst the residents of four rural towns near Pavia in northern Italy. The population included a 40% sample of the residents between 65 and 69 years old and all residents of 70 years old or older. A door-to-door neuropsychological screening was followed by neurological examination on individuals scoring low at the screening. Of the 1670 subjects who completed the screening, 42.3% scored under the cut-off point. The prevalence of cognitive deficit was higher in women, even accounting for age. Of those who scored under the cut-off point, 336 underwent neurological examination, yielding a prevalence of dementia of 15% (from 1.6% between the ages of 65 and 69; 35% at the age of 85) in women and 5% (from 7% between the ages of 75 and 79; 27% at the age of 85 or more) in men.