While Alzheimer’s is the most common form of dementia, there are many other types as well. In this section, we explain the causes and main signs of some of the different types of dementia. Vascular dementia Vascular dementia is the second most common type of dementia, accounting for roughly 15-20% of dementia cases in Europe. Dementia with Lewy bodies Dementia with Lewy bodies (DLB) is named after the damaging protein deposits that cause the disease, known as Lewy bodies. Frontotemporal dementia In frontotemporal dementia, the frontal and temporal lobes of the brain become damaged. Mixed dementia About 1 in 10 people with dementia are diagnosed with more than one type of dementia. Young onset dementia When a person develops dementia before the age of 65, this is known as “young onset dementia”.