Dementia Care Site Map
Younger Onset Dementia


Dementia is a disease in which there is deterioration in memory, thinking, behaviour and the ability to perform everyday activities. Although dementia mainly affects people over the age of 65 it is not a normal part of ageing.


Dementia can also occur in people under the age of 65 and although rare it can affect people in their 40's and 50's.


Dementia affecting people prior to the age of 65 is generally known as Younger Onset Dementia (YOD).


Causes of Younger Onset Dementia

There are many causes of YOD which can include Alzheimer's disease, Alcohol-related dementia, Vascular dementia and Frontotemporal dementia.

In addition, dementia in younger people can often be secondary to another medical illness such as multiple sclerosis, Huntington's disease, Parkinson's disease, HIV, Down syndrome or epilepsy.


Scientists have identified several rare genes that can cause Alzheimer's and people who inherit these rare genes can develop symptoms in their 30s, 40s and 50s. 'Familial Alzheimer's' disease can affect many family members and multiple generations however this is very rare and currently it is reported that there are only a few hundred cases worldwide.


As dementia is rare in younger people it may be difficult to diagnose accurately. Your doctor will be able to advise you on the best treatments if dementia has been diagnosed.



There were an estimated 23,900 Australians under the age of 65 who had dementia in 2011, with men accounting for just over half (53%). Those under 65 represented 8% of all people with dementia in Australia.


By comparison, in the first Dementia in Australia (AIHW 2007) report, projections suggested there would be 10,000 people aged under 65 with dementia in 2011. Meanwhile, DAE (2011) estimated that there were 16,329 people aged under 65 with dementia in 2011.


The higher estimate presented in this report is, however, in line with a recent World Health Organization (WHO 2012) report which suggests that the prevalence of younger onset dementia is often underestimated and that such cases account for about 6% to 9% of all dementia cases.


Information provided by AIHW - Australian Institute of Health and Welfare

Support available

See What's On for information about new YOD cafe

Young Onset Key Worker

This role is provided within Gippsland, by Alzheimer's Australia Vic.  Information regarding this role can be found by clicking here, or alternately call the National Dementia Helpline on 1800 100 500 for more information.