The precise cause of LBD is unknown, but scientists are learning more about its biology and genetics. For example, they know that an accumulation of Lewy bodies is associated with a loss of certain neurons in the brain that produce two important neurotransmitters, chemicals that act as messengers between brain cells.
One of these messengers, acetylcholine, is important for memory and learning. The other, dopamine, plays an important role in behavior, cognition, movement, motivation, sleep, and mood.
Scientists are also learning about risk factors for LBD. Age is considered the greatest risk factor. Most people who develop the disorder are over age 50. Other known risk factors for LBD include the following:
- Diseases and Health Conditions – Certain diseases and health conditions, particularly Parkinson’s disease and REM sleep behavior disorder, are linked to a higher risk of LBD.
- Genetics – While having a family member with LBD may increase a person’s risk, LBD is not normally considered a genetic disease. A small percentage of families with dementia with Lewy bodies has a genetic association such as a variant of the GBA gene, but in most cases, the cause is unknown. At this time, no genetic test can accurately predict whether someone will develop LBD. Future genetic research may reveal more information about causes and risk.
- Lifestyle – No specific lifestyle factor has been proven to increase one’s risk for LBD. However, some studies suggest that a healthy lifestyle—including regular exercise, mental stimulation, and a healthy diet—might reduce the chance of developing age-associated dementias.