Lewy Body Dementia, Dementia with Lewy Bodies, Diffuse Lewy Body Disease: Are They All the Same?
Lewy body dementia (LBD) is sometimes known by other names. These include dementia with Lewy bodies, Lewy body variant of Alzheimer's disease, diffuse Lewy body disease, and cortical Lewy body disease. All these terms refer to the same condition.1-3
What is Lewy body dementia?
LBD is a progressive brain disorder. It is the second most common form of degenerative dementia.1 It affects about 1.4 million people in the United States.1
LBD is characterized by the presence of Lewy bodies in the nerve cells of the brain. Lewy bodies are abnormal protein deposits in the brain. These deposits disrupt how nerve cells in the brain control memory, thinking, movement, and sleep.2
Lewy bodies also damage chemicals that are important to brain function. This can affect bodily functions like blood pressure control, body temperature regulation, and bladder and bowel function.3
Lewy bodies are also found in people with other conditions, including Alzheimer’s and Parkinson’s disease. However, not all people with Parkinson’s disease develop LBD, even if they have Lewy bodies.2
What are the symptoms of Lewy body disease?
LBD is a progressive disease, which means that symptoms start slowly and get worse over time. How quickly symptoms develop varies from person to person. It also depends on age, overall health, and severity of symptoms.4
Dementia is one of the first symptoms of LBD. This usually includes issues with attention, planning, multitasking, problem-solving, and reasoning. Dementia may also cause confusion and affect a person’s mood, behavior, and judgment.2
Other common symptoms include:1
- Anxiety, delusions, and paranoia
- Depression and apathy
- Hallucinations, including visual and auditory hallucinations
- Irregular blood pressure, body temperature, and bladder and bowel function
- Signs of parkinsonism, including muscle rigidity, tremor, and balance issues
- Sleep disorders, including REM sleep behavior disorder, insomnia, and restless leg syndrome
- Unpredictable changes in alertness, attention, and concentration
Who is at risk for Lewy body dementia?
The main risk factor for LBD is age. Most people who develop the disease are over age 50. One study found that people between 70 and 79 are at the highest risk.5
Research shows that gender also plays a role in LBD. One study found that men are 2 times more likely than women to develop the disease.5
Some diseases and health conditions, including Parkinson’s disease and REM sleep behavior disorder, have been linked to a higher risk of LBD. Only about 10 percent of LBD cases are hereditary.4 There is currently no genetic test that can predict whether someone will develop LBD.
How is LBD different from Parkinson’s and Alzheimer’s disease?
LBD is an umbrella term for 2 similar diagnoses:
- Dementia with Lewy bodies
- Parkinson’s disease dementia
Both diseases cause the same underlying changes in the brain. Over time, both diseases lead to similar symptoms. The main difference between the 2 is when a person’s cognitive and movement symptoms begin.2
Dementia with Lewy bodies affects cognitive abilities that can include memory and reasoning. Dementia is always the first symptom. Movement symptoms – tremors, stiffness, and balance issues – come later.6
Parkinson’s disease dementia is a type of dementia that develops after a diagnosis of PD. Nearly all patients with PD experience movement symptoms first. Over time, cognitive symptoms may appear. It is important to note that not all people with PD develop dementia.6
A decline in cognitive abilities is a symptom of both LBD and Alzheimer’s disease. However, there are some LBD symptoms that help differentiate the 2 diseases. These include hallucinations, sleep disorders, and balance problems/falls.7
How is Lewy body disease diagnosed?
There are currently no medical tests to diagnose LBD with certainty. Doctors usually diagnose LBD based on a person’s medical history, an examination, and other blood tests or brain scans.8 This helps rule out other possible causes of behavioral issues, dementia, or movement disorders.
What is the prognosis for someone with LBD?
Since LBD progresses differently for each person, it is not possible to determine how long someone may live with the disease. One study found that people with LBD usually live 5 to 7 years after their symptoms appear.9
Are you or a loved one living with LBD? Do you have questions about the differences between PD and LBD? Share in the comments below!
Have you or a loved one ever tried speech therapy?