In this condition, protein deposits of Alpha-synuclein called lewy bodies develop in nerve cells in brain regions involved in memory, reasoning, perception, thinking, behavior and movement. Many people with DLB experience movement symptoms such as hunched posture, rigid muscles, shuffling walk and trouble initiating movement. Lewy body dementia is the second most common kind of dementia after Alzheimer’s disease that gradually causes decline in mental ability. It may sometimes causes visual hallucination and unusual behaviors such as having conversations with deceased loved ones. It sometimes exists in pure form, or with other brain changes, including those commonly observed in Alzheimer's and Parkinson's diseases.
In a study to report the prevalence of dementia in a community-dwelling Brazilian elderly population and correlate prevalence data with educational and socioeconomic levels, Dementia was diagnosed in 118 subjects, corresponding to a prevalence of 7.1%. Lewy-body dementia was found to be causative for dementia in 2 of 118 cases accounting to 1.7%.