Dementia with Lewy Bodies (DLB) is associated with the development of abnormal brain tissues known as Lewy bodies (and Lewy neurites) which are numerous small collections of an abnormal 'α-synuclein' protein within diseased brain neurons.

However, it's not known whether the Lewy bodies are a product of the disease, or a cause of the disease, or even a protective mechanism against it,

It is unclear whether Lewy bodies and Lewy neurites have a neuroprotective or neurotoxic role and to what extent they contribute to the clinical picture because some individuals have severe α-synuclein pathology at autopsy but no clinical symptoms of Lewy body dementia.

Source : Lancet. 2015 Oct 24; 386(10004): 1683–1697.

LikeAlzheimer's Diseaseplugin-autotooltip__plain plugin-autotooltip_bigAlzheimer's disease

"Alzheimer’s disease is a chronic progressive neuro-degenerative disorder characterised by three primary groups of symptoms. The first group (cognitive dysfunction) includes memory loss, language difficulties, and executive dysfunction (that is, loss of higher level planning and intellectual coordination skills). The second group comprises psychiatric symptoms and behavioural disturbances — for example, depression, hallucinations, delusions, agitation — collectively termed …, DLB features profound problems with dopamine transmission within the brain. The faulty dopamine transmission causes confusion, hallucinations, tremors, sleep disorders and falls etc. It's rarely affects people under 65.

The cause is unknown, but like Alzheimer's, it's assumed to be a combination of as-yet-unidentified genetic and environmental factors.

There's currently no cure, or any treatment that will slow down its progression - though various treatments can help alleviate some symptoms.

Further info UK NHS