Stages of Lewy Body Dementia

Lewy body dementia (LBD) progresses in stages, similar to Alzheimer’s disease. It's what happens during these stages that makes the two conditions different.

This article explains the progression of Lewy body dementia as it proceeds through three stages.

Stages of Lewy Body Dementia

Lewy body dementia usually takes five to eight years to progress from diagnosis to death. Some cases may progress faster, while others may progress much more slowly. Regardless of the speed of progression, the timeline of Lewy body dementia is usually distinguished by early, middle, and late stages.

Early Stages

In general, the earlier stages of Lewy body dementia may involve hallucinations or other distortions of reality such as delusions, restlessness, acting out dreams during sleep (called REM sleep disorder), and some movement difficulties.

Some people may appear to "freeze" or get stuck as they move about. Others may develop urinary urgency and incontinence. Unlike Alzheimer's disease, memory is usually still fairly intact in the early stages. But confusion and some mild cognitive changes may be present.

Middle Stages

As Lewy body dementia progresses, symptoms develop that more strongly resemble Parkinson's disease. These symptoms include falls, increased problems with motor functions, difficulty with speech, swallowing problems, and greater paranoia and delusions.

Cognition also continues to decline, with shorter attention and significant periods of confusion. 

Later Stages

In the later stages of Lewy body dementia, extreme muscle rigidity and sensitivity to touch develop. People need assistance with almost all activities of daily living. Speech is often very difficult and may be whispered. Some people stop talking altogether.

Lewy body dementia typically causes the individual to become very susceptible to pneumonia and other infections because of weakness.

It is impossible to predict how long it will take to progress through any stage of Lewy body dementia. According to one study, end-stage Lewy body dementia could last between two months and one year. For some people, however, death may occur quickly and unexpectedly.

How Lewy Body Dementia Progresses

Lewy body dementia and Alzheimer's disease are both forms of dementia. Lewy body dementia, however, progresses somewhat differently from Alzheimer's disease. Notably, the symptoms—especially memory loss—can fluctuate greatly with LBD. Alzheimer's tends to worsen more steadily.

Understanding this variation in cognition can be helpful for caregivers. Without this knowledge, it may seem like the person with Lewy body dementia is "forgetting" on purpose.

This fluctuation can also make it feel like the person is moving back and forth from one stage to another. In reality, the variation in functioning is a normal feature within each stage of the disease.

Understanding Lewy Body Dementia

Lewy body dementia symptoms are so similar to those of other forms of dementia that LBD can be misdiagnosed. This might make more sense when you consider that there are many types of dementia.

It may help to think of dementia as one large (and cruel) "umbrella" that slowly robs people of their ability to think, talk, remember, and use their bodies. Many diseases crowd underneath this umbrella, including:

• Alzheimer’s disease
• Frontotemporal dementia (FTD)
• Huntington’s disease
• Lewy body dementia
• Mixed dementia
• Parkinson’s disease dementia
• Vascular dementia

Of these, Alzheimer's is the most common. And it shares many symptoms with LBD, which adds to the confusion.

But there are certain differences between Alzheimer's and LBD that can help clarify a diagnosis.

People with Alzheimer's usually suffer greater memory loss than those with LBD. Otherwise, people with LBD are more likely to:

• Contend with dizziness and falls
• Deal with REM sleep disorder
• Experience more erratic body movements
• Report more hallucinations and delusions
• Struggle with incontinence

With dementia with Lewy bodies, cognitive changes may appear earlier than, about the same time, or shortly after any physical changes surface.

Summary

Lewy body dementia is one of many types of dementia (with Alzheimer's being the most common). A major difference with Lewy body dementia is that its symptoms can fluctuate significantly from day to day. It is marked by early, middle, and late stages.

A Word From Verywell

Learning what to expect can be helpful in coping with Lewy body dementia. But the biggest thing to expect is the unexpected. The unpredictability of Lewy body dementia is one of its characteristics. Knowing this can be reassuring to both the individual living with the disease as well as family and caregivers.