The Lewy body dementias are as a group the second most common form of neurodegenerative dementia after AD as of 2021.<unk>  itself is one of the three most common types of dementia, along with AD and vascular dementia. The diagnostic criteria for<unk>  before 2017 were highly specific, but not very sensitive, so that more than half of cases were missed historically.<unk>  was under-recognized as of 2021, and there is little data on its epidemiology. The incidence and prevalence of<unk>  are not known accurately, but estimates are increasing with better recognition of the condition since 2017. About 0.4% of those over the age 65 are affected with<unk> , and between per 1,000 people develop the condition each year. Symptoms usually appear between the ages of 50 and 80, (median 76) and it is not uncommon for it to be diagnosed before the age of 65.<unk>  is thought to be slightly more common in men than women, but a 2014 review challenged that view, and said that the gender distribution was unclear. An estimated 10 to 15% of diagnosed dementias are Lewy body type, but estimates range as high as 23% for those in clinical studies. A French study found an incidence among persons 65 years and older almost four times higher than a US study per 100,000 person-years), but the US study may have excluded people with only mild or no parkinsonism, while the French study screened for parkinsonism. Neither of the studies assessed systematically for RBD, so<unk>  may have been underdiagnosed in both studies. A door-to-door study in Japan found a prevalence of 0.53% for persons 65 and older, and a Spanish study found similar results.
Dementia with Lewy bodies
Parkinson's disease
Multiple system atrophy
Lewy body dementias
Subcortical dementia
Parkinson's disease dementia
Frontotemporal dementia
Vascular dementia