2022 ICD-10-CM Code G31.83

Dementia with Lewy bodies

Version 2021

Valid for Submission

ICD-10:G31.83
Short Description:Dementia with Lewy bodies
Long Description:Dementia with Lewy bodies

Code Classification

  • Diseases of the nervous system (G00–G99)
    • Other degenerative diseases of the nervous system (G30-G32)
      • Oth degenerative diseases of nervous system, NEC (G31)

G31.83 is a billable diagnosis code used to specify a medical diagnosis of dementia with lewy bodies. The code G31.83 is valid during the fiscal year 2022 from October 01, 2021 through September 30, 2022 for the submission of HIPAA-covered transactions.

The ICD-10-CM code G31.83 might also be used to specify conditions or terms like abnormal behavior, dementia associated with parkinson's disease, diffuse lewy body disease, diffuse lewy body disease with spongiform cortical change, lewy body dementia with behavioral disturbance , parkinsonism with dementia of guadeloupe, etc.

Tabular List of Diseases and Injuries

The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code G31.83:


Inclusion Terms

Inclusion Terms
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code G31.83 are found in the index:

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

Convert G31.83 to ICD-9 Code

Information for Patients


Lewy Body Dementia

What is Lewy body dementia (LBD)?

Lewy body dementia (LBD) is one of the most common types of dementia in older adults. Dementia is a loss of mental functions that is severe enough to affect your daily life and activities. These functions include

What are the types of Lewy body dementia (LBD)?

There are two types of LBD: dementia with Lewy bodies and Parkinson's disease dementia.

Both types cause the same changes in the brain. And, over time, they can cause similar symptoms. The main difference is in when the cognitive (thinking) and movement symptoms start.

Dementia with Lewy bodies causes problems with thinking ability that seem similar to Alzheimer's disease. Later, it also causes other symptoms, such as movement symptoms, visual hallucinations, and certain sleep disorders. It also causes more trouble with mental activities than with memory.

Parkinson's disease dementia starts as a movement disorder. It first causes the symptoms of Parkinson's disease: slowed movement, muscle stiffness, tremor, and a shuffling walk. Later on, it causes dementia.

What causes Lewy body dementia (LBD)?

LBD happens when Lewy bodies build up in parts of the brain that control memory, thinking, and movement. Lewy bodies are abnormal deposits of a protein called alpha-synuclein. Researchers don't know exactly why these deposits form. But they do know that other diseases, such as Parkinson's disease, also involve a build-up of that protein.

Who is at risk for Lewy body dementia (LBD)?

The biggest risk factor for LBD is age; most people who get it are over age 50. People who have a family history of LBD are also at higher risk.

What are the symptoms of Lewy body dementia (LBD)?

LBD is a progressive disease. This means that the symptoms start slowly and get worse over time. The most common symptoms include changes in cognition, movement, sleep, and behavior:

In the early stages of LBD, symptoms can be mild, and people can function fairly normally. As the disease gets worse, people with LBD need more help due to problems with thinking and movement. In the later stages of the disease, they often cannot care for themselves.

How is Lewy body dementia (LBD) diagnosed?

There isn't one test that can diagnose LBD. It is important to see an experienced doctor to get a diagnosis. This would usually be specialist such as a neurologist. The doctor will

LBD can be hard to diagnose, because Parkinson's disease and Alzheimer's disease cause similar symptoms. Scientists think that Lewy body disease might be related to these diseases, or that they sometimes happen together.

It's also important to know which type of LBD a person has, so the doctor can treat that type's particular symptoms. It also helps the doctor understand how the disease will affect the person over time. The doctor makes a diagnosis based on when certain symptoms start:

What are the treatments for Lewy body dementia (LBD)?

There is no cure for LBD, but treatments can help with the symptoms:

Support groups can also be helpful for people with LBD and their caregivers. Support groups can give emotional and social support. They are also a place where people can share tips about how to deal with day-to-day challenges.

NIH: National Institute of Neurological Disorders and Stroke


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Dementia with Lewy bodies

Dementia with Lewy bodies is a nervous system disorder characterized by a decline in intellectual function (dementia), a group of movement problems known as parkinsonism, visual hallucinations, sudden changes (fluctuations) in behavior and intellectual ability, and acting out dreams while asleep (REM sleep behavior disorder). This condition typically affects older adults, most often developing between ages 50 and 85. The life expectancy of individuals with dementia with Lewy bodies varies; people typically survive about 5 to 7 years after they are diagnosed.

REM sleep behavior disorder may be the first sign of dementia with Lewy bodies. It can occur years before other symptoms appear. Individuals with REM sleep behavior disorder act out their dreams, talking and moving in their sleep when they should be still. This behavior becomes less pronounced as dementia with Lewy bodies worsens and additional features develop.

Dementia is often the second major feature to develop in dementia with Lewy bodies. Initially, this intellectual decline may be mild or seem to come and go. In this condition, dementia often leads to impaired ability to perform visual-spatial tasks such as assembling puzzles. Affected individuals may also have poor problem-solving skills (executive functioning), speech difficulties, and reduced inhibitions. Problems with memory typically do not occur until later.

Most people with dementia with Lewy bodies experience visual hallucinations, which often involve people or animals. Fluctuations in behavior and thought processes (cognition) include sudden changes in attention, unintelligible speech, and brief episodes of altered consciousness that may appear as staring spells.

Parkinsonism is usually the last major feature to develop in people with dementia with Lewy bodies, although it can appear earlier in some individuals. The movement problems typically include tremors, rigidity, unusually slow movement (bradykinesia), and impaired balance and coordination (postural instability). Affected individuals may require walking aids or wheelchair assistance over time.

Individuals with dementia with Lewy bodies may also experience a sharp drop in blood pressure upon standing (orthostatic hypotension), fainting episodes (syncope), reduced sense of smell, increased saliva production and drooling, difficulty controlling the flow of urine (incontinence), or constipation.


[Learn More in MedlinePlus]

What Is Lewy Body Dementia? Lewy body dementia (LBD) is a disease associated with abnormal deposits of a protein called alpha-synuclein in the brain.
[Learn More in MedlinePlus]

Code History

  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016 (First year ICD-10-CM implemented into the HIPAA code set)