<unk>  is the term used for cases of<unk> 's disease diagnosed in patients under the age of 65. It is an uncommon form of<unk> 's, accounting for only 5-10% of all<unk> 's cases. Approximately half the cases of<unk><unk><unk> 's are Familial<unk> 's disease, in which a genetic predisposition leads to the disease. The other incidences of<unk><unk><unk> 's, however, share the same traits as the late<unk>  form, commonly referred to simply as<unk> 's disease, and little is understood about how it develops.
Non-Familial<unk><unk><unk> 's can develop in people who are in their 30s or 40s, although that is extremely rare. The majority of sufferers are in their 50s or<unk>  60s. Familial<unk> 's can appear as<unk>  as 16 years of age.
Sometimes this disease is referred to as<unk><unk>  dementia," although<unk> 's disease is just one type of dementia.
Early-onset Alzheimer's disease
Multi-infarct dementia
Dementia with Lewy bodies
Pick's disease
Semantic dementia
Parkinson's disease
Creutzfeldt-Jakob disease
Canavan disease