As a result of the higher life expectancy of women, age-related illnesses such as dementia occur with quite different frequencies in men and women. The present contribution provides a survey of sex-related differences in the prevalence, incidence, diagnostic distribution and duration of late-life dementia.

Review of epidemiological studies.

In western industrialized countries, more than 70% of the dementia patients are women; less than 30% are men. Since women with dementia are on the average older and more frequently widowed than male dementia patients, the consequences are correspondingly different. Women are in greater need of care in an old-age home, whereas men have better chances of being cared for in a home environment. Epidemiological studies indicate a more frequent incidence of vascular dementia among men and of degenerative dementia among women. Furthermore, the results give rise to the suspicion that the incidence among women is higher in the most advanced age groups and that some risk factors are more closely associated with the occurrence of a dementia in women than in men.

There are considerable sex differences in the prevalence, incidence, duration, the lifetime risk and the consequences of late-life dementia. The risk of contracting the illness possibly increases with age more steeply for women than for men. This could be an indication that the illnesses are at least partly determined by different risk factors or that there are sex-risk-factor interactions.