Lewy body dementia (LBD) is the second most common form of degenerative dementia after Alzheimer’s.
It is the form Robin Williams was diagnosed with before he took his own life in 2014.
Unlike Alzheimer’s, LBD affects the brain regions responsible for vision – as opposed to memory.
That means sufferers may start with memory loss, but over time the more debilitating symptoms will be powerful hallucinations, nightmares and spatial-awareness problems.
LBD is closely connected to Parkinson’s disease, meaning that many sufferers will develop Parkinson’s as well – as happened to Robin Williams.
The most common symptoms include:
- Impaired thinking, such as loss of executive function (planning, processing information), memory, or the ability to understand visual information.
- Fluctuations in cognition, attention or alertness;
- Problems with movement including tremors, stiffness, slowness and difficulty walking
- Visual hallucinations (seeing things that are not present)
- Sleep disorders, such as acting out one’s dreams while asleep
- Behavioral and mood symptoms, including depression, apathy, anxiety, agitation, delusions or paranoia
- Changes in autonomic body functions, such as blood pressure control, temperature regulation, and bladder and bowel function.
HOW IT STARTS:
Many sufferers will first develop Parkinson’s, suffering physical disabilities, before doctors diagnose their dementia. That is what happened to the late revered actor Robin Williams.
Some will start with memory loss that could be mistaken for the more common Alzheimer’s disease. Over time, they will develop symptoms more clearly associated with LBD.
WHAT CAUSES IT:
There is no known cause. What we do know is that risk increases with age.
At a cellular level, LBD is characterized by tiny clumps of abnormal proteins produced by the brain when its cells are not working properly.
They cause memory problems, although these don’t tend to be as severe as with Alzheimer’s — which is linked to a build-up of the protein beta-amyloid.
Another key difference is that Lewy body dementia affects regions of the brain responsible for vision, causing powerful hallucinations, nightmares and spatial-awareness problems.