G31.83

Billable

Neurocognitive disorder with Lewy bodies

HCC Category Mapping

V28HCC 127 — Dementia, Mild or Unspecified

0.464

RxHCCHCC 112 — Dementia and Other Specified Brain Disorders

0.000

What This Code Means

A type of dementia characterized by abnormal protein deposits called Lewy bodies in the brain, causing cognitive decline, movement problems, and behavioral changes.

Coding Tips

•Lewy body dementia often presents with Parkinson-like symptoms; code any movement disorders separately
•Document hallucinations and behavioral symptoms as they are key diagnostic features

Clinical Significance

Neurocognitive disorder with Lewy bodies (Lewy body dementia) is the second most common type of progressive dementia after Alzheimer's disease. It is characterized by fluctuating cognition, visual hallucinations, and parkinsonism, creating complex management challenges. Accurate identification is critical because these patients are highly sensitive to antipsychotic medications, which can be life-threatening.

Documentation Requirements

✓Provider documentation specifically stating Lewy body dementia or neurocognitive disorder with Lewy bodies
✓Documentation of core clinical features: fluctuating cognition, recurrent visual hallucinations, and/or parkinsonism
✓Cognitive assessment results (MMSE, MoCA) showing progressive decline
✓REM sleep behavior disorder documentation if present (supportive feature)
✓Medication list noting sensitivity to neuroleptics/antipsychotics
✓Functional status assessment and care plan

Use Additional Code

code, if applicable, to identify mild neurocognitive disorders due to known physiological condition (F06.7-)

Commonly Confused Codes

G30.0/G30.1/G30.9 — Alzheimer's disease; primarily memory loss without prominent hallucinations or parkinsonism G20 — Parkinson's disease; when dementia develops after established Parkinson's, use G20 + F02.8x instead G31.09 — Other frontotemporal neurocognitive disorder; behavioral/language variants without parkinsonism or hallucinations F02.80/F02.81 — Dementia in other diseases; these are manifestation codes used alongside G31.83 G31.85 — Corticobasal degeneration; asymmetric motor findings without the hallucination feature

Code Hierarchy

└G31Other degenerative diseases of nervous system, not elsewhere classified └G31.8Other specified degenerative diseases of nervous system └G31.83Neurocognitive disorder with Lewy bodies

└G31.83Neurocognitive disorder with Lewy bodies