ICD-10 Code for Dementia: Complete 2026 Coding, Subtypes & Billing Guide

Published:
06/12/2026
Last Updated:
06/12/2026

Stop defaulting to F03.90. Map every dementia case to the correct ICD-10 code by subtype, severity, and behavioral feature, with 2026 CPT and billing rules.

Summary: “The ICD-10 code for dementia is F03.90 when the dementia is unspecified, of unspecified severity, and documented without behavioral or psychiatric features. F03.90 is the default billable code. The correct code changes based on 3 documented variables: etiology (the underlying disease), severity (mild, moderate, severe), and behavioral or psychiatric features (agitation, psychosis, mood, anxiety).”

Dementia coding accuracy carries direct financial consequences. An estimated 7.2 million Americans age 65 and older live with Alzheimer’s dementia, the most common form of dementia. U.S. healthcare, long-term care, and hospice spending for Alzheimer’s disease and related dementias is projected to reach $384 billion in 2025. Dementia diagnosis coding also plays a significant role in Medicare Advantage risk adjustment and CMS reimbursement methodologies.

Dementia generates recurring claims across primary care, neurology, geriatrics, and psychiatry. A single coding error, such as reporting an unspecified dementia code when a specific etiology is documented or failing to sequence the underlying disease correctly, can lead to claim denials, medical necessity reviews, audit exposure, inaccurate risk adjustment, and lost reimbursement.

CDC data shows that more than 40% of nursing home residents, hospice patients, and residential care community residents have Alzheimer’s disease or another dementia diagnosis. For coders and billers, dementia remains one of the most documentation-sensitive areas in ICD-10-CM. Reimbursement frequently depends on identifying the correct underlying etiology, including Alzheimer’s disease, vascular dementia, Lewy body dementia, Parkinson’s disease dementia, and frontotemporal degeneration.

This guide covers the full ICD-10-CM dementia code set, including sequencing rules, etiology-manifestation conventions, documentation requirements, CPT coding opportunities, reimbursement considerations, denial risks, and the coding mistakes that most commonly cost healthcare organizations revenue.

Table of Contents

What Is Dementia?

Dementia is a syndrome of acquired cognitive decline severe enough to interfere with daily function. Dementia is not one disease. Dementia is a set of symptoms produced by underlying conditions that damage brain function, including Alzheimer’s disease, cerebrovascular disease, Lewy body disease, frontotemporal degeneration, and Parkinson’s disease.

Dementia affects 6 cognitive domains: memory, executive function, language, attention, visuospatial ability, and social cognition. Alzheimer’s disease accounts for 60–80% of dementia cases. Vascular dementia accounts for 5–10% of cases. Dementia prevalence doubles approximately every 5 years after age 65.

ICD-10-CM encodes dementia on 3 axes. The first axis is etiology, the underlying disease that produces the cognitive decline. The second axis is severity, graded as mild, moderate, or severe. The third axis is the presence of behavioral and psychological symptoms of dementia (BPSD). The “What is the ICD-10 code for dementia?” question has no single answer, because the code is built from those 3 documented variables.

Dementia Coding and Billing Statistics

Dementia coding operates inside a high-volume, high-cost, high-denial environment. The following statistics establish the scale and the financial stakes of accurate dementia coding.

Metric	Figure	Source
Americans 65+ with Alzheimer’s dementia (2025)	7.2 million	Alzheimer’s Association 2025
Projected Alzheimer’s prevalence (2026)	7.4 million	Alzheimer’s Association 2026
Annual US dementia care cost (excludes unpaid care, 2025)	$384 billion	Alzheimer’s Association 2025
Excess annual per-person cost vs. non-dementia patients	~$25,000	BrightFocus / Facts & Figures
Early-stage dementia cases undiagnosed	50–75%	NIH / PMC research
Average delay from symptom onset to diagnosis	~32 months	PMC research

Dementia prevalence rises while diagnosis lags. The 50–75% early-stage underdiagnosis rate means a large share of dementia encounters reach coding without a documented etiology, defaulting to F03.90 and forfeiting specificity.

How to Read the Dementia Code Tables

The F01, F02, and F03 dementia families share one complex structure: severity rows and behavioral-feature columns. Each table below presents that full matrix, so every code in a family reads at a glance. The 4 severity rows are: unspecified severity, mild, moderate, and severe. The 6 behavioral-feature columns are: without behavioral disturbance, with agitation, with other behavioral disturbance, with psychotic disturbance, with mood disturbance, and with anxiety.

Navigating this intricate grid alongside your daily evaluation and testing codes requires a highly disciplined approach, which is why utilizing a specialized billing guide for neurology practices is essential for maintaining revenue integrity. Etiology codes (G-codes and others) appear in separate 2-column tables, because etiology is sequenced before the F02 manifestation code.

Unspecified Dementia Codes (F03 Series)

The ICD-10 code for unspecified dementia uses the F03 family when no etiology is documented. The ICD-10 code for dementia unspecified without behavioral disturbance is F03.90. The following matrix lists every F03 code across severity and behavioral features.

Severity	Without behavioral	With agitation	Other behavioral	With psychotic	With mood	With anxiety
Unspecified severity	F03.90	F03.911	F03.918	F03.92	F03.93	F03.94
Mild	F03.A0	F03.A11	F03.A18	F03.A2	F03.A3	F03.A4
Moderate	F03.B0	F03.B11	F03.B18	F03.B2	F03.B3	F03.B4
Severe	F03.C0	F03.C11	F03.C18	F03.C2	F03.C3	F03.C4

F03.9 is the non-billable parent code and rejects on claims. The billable ICD-10 code for dementia at the unspecified level is F03.90. The ICD-10 code for dementia without behavioral disturbance uses the “without behavioral” column. The ICD-10 code for unspecified dementia with behavioral disturbance selects the matching behavioral column. The 2025 ICD-10 code for dementia and 2026 ICD-10 code for dementia share this F03 structure; the 2021 ICD-10 code for dementia and 2022 ICD-10 code for dementia predate the severity expansion introduced in the 2023 ICD-10 code for dementia update.

Severity Codes: Mild, Moderate, Severe, Advanced, End-Stage

Dementia severity occupies the row axis of each family table. The table below maps severity terms to the unspecified-etiology F03 codes without behavioral disturbance.

Severity term	Maps to	F03 code (no behavioral)
Mild / early-stage	Mild	F03.A0
Moderate	Moderate	F03.B0
Severe / advanced / end-stage	Severe	F03.C0
Unspecified	Unspecified severity	F03.90

The ICD-10 code for mild dementia maps to F03.A0. The ICD-10 code for early dementia maps to the mild tier when “early” describes the stage. The ICD-10 code for moderate dementia maps to F03.B0. The ICD-10 codes for severe dementia, advanced dementia, and end-stage dementia map to F03.C0. The ICD-10 code for severe dementia with behavioral disturbance and the ICD-10 code for advanced dementia with behavioral disturbance select F03.C11 or F03.C18. The ICD-10 code for advanced dementia, unspecified, and ICD-10 code for end-stage dementia unspecified, resolve to F03.C0. Severity documentation uses the FAST, CDR, and GDS staging instruments.

Vascular Dementia Codes (F01 Series)

The ICD-10 code for vascular dementia without behavioral disturbance is F01.50. Vascular dementia results from cerebrovascular disease, including stroke and small-vessel ischemia. Multi-infarct dementia codes within this family. The following matrix lists every F01 vascular dementia code.

Severity	Without behavioral	With agitation	Other behavioral	With psychotic	With mood	With anxiety
Unspecified severity	F01.50	F01.511	F01.518	F01.52	F01.53	F01.54
Mild	F01.A0	F01.A11	F01.A18	F01.A2	F01.A3	F01.A4
Moderate	F01.B0	F01.B11	F01.B18	F01.B2	F01.B3	F01.B4
Severe	F01.C0	F01.C11	F01.C18	F01.C2	F01.C3	F01.C4

The ICD-10 code for vascular dementia unspecified is F01.50. The ICD-10 code for vascular dementia with behavioral disturbance selects F01.511 or F01.518. The ICD-10 code for vascular dementia without behavioral disturbance is F01.50. The ICD-10 code for vascular dementia with anxiety is F01.54. The ICD-10 code for vascular dementia with depression uses the mood column (F01.53). The ICD-10 code for vascular dementia with agitation is F01.511. The ICD-10 code for mild vascular dementia, ICD-10 code for moderate vascular dementia, and ICD-10 code for severe vascular dementia use the A, B, and C rows. The ICD-10 code for multi-infarct dementia codes within the F01 vascular family.

Dementia in Other Diseases Classified Elsewhere (F02 Series)

The ICD-10 code for dementia in other diseases classified elsewhere is F02.80 without behavioral disturbance. F02 codes are manifestation codes. The underlying disease (etiology) is sequenced first. F02.80 never stands alone on a claim. The following matrix lists every F02 code.

Severity	Without behavioral	With agitation	Other behavioral	With psychotic	With mood	With anxiety
Unspecified severity	F02.80	F02.811	F02.818	F02.82	F02.83	F02.84
Mild	F02.A0	F02.A11	F02.A18	F02.A2	F02.A3	F02.A4
Moderate	F02.B0	F02.B11	F02.B18	F02.B2	F02.B3	F02.B4
Severe	F02.C0	F02.C11	F02.C18	F02.C2	F02.C3	F02.C4

The F02 code carries the dementia manifestation and the behavioral feature. The etiology code carries the underlying disease. A claim pairs the etiology code first, then the F02 code. Submitting an F02 code without its etiology code triggers denial.

Etiology Codes for Dementia Subtypes

Each dementia subtype carries a distinct etiology code, sequenced before the F02 manifestation code. The following table lists the primary etiology codes.

Subtype	Etiology code	Description (FY2026)	Pair with
Alzheimer’s, early onset	G30.0	Alzheimer’s disease with early onset	F02.8x
Alzheimer’s, late onset	G30.1	Alzheimer’s disease with late onset	F02.8x
Alzheimer’s, other	G30.8	Other Alzheimer’s disease	F02.8x
Alzheimer’s, unspecified	G30.9	Alzheimer’s disease, unspecified	F02.8x
Lewy body	G31.83	Dementia with Lewy bodies	F02.8x
Frontotemporal, Pick’s	G31.01	Pick’s disease	F02.8x
Frontotemporal, other	G31.09	Other frontotemporal degeneration	F02.8x
Parkinson’s disease	G20.x	Parkinson’s disease (select FY2026 sub-code)	F02.8x
Senile degeneration of brain	G31.1	Senile degeneration of brain, NEC	F02.8x

Etiology codes establish the cause. The F02 code records the dementia and its severity and behavioral features. The 2 codes together fully describe etiology-specific dementia.

Alzheimer’s Disease Dementia

The ICD-10 code for alzheimer’s dementia uses G30.9 (or G30.0/G30.1) plus an F02 code. Alzheimer’s disease presents with progressive memory loss as the earliest feature. The table below shows the most-used Alzheimer’s combinations.

Scenario	Etiology code	+ Manifestation code
Alzheimer’s, unspecified, no behavioral	G30.9	F02.80
Alzheimer’s with agitation	G30.9	F02.811
Alzheimer’s with anxiety	G30.9	F02.84
Early-onset Alzheimer’s	G30.0	F02.8x
Severe / advanced Alzheimer’s	G30.9	F02.C0

The ICD-10 code for Alzheimer’s dementia without behavioral disturbance is G30.9 + F02.80. The ICD-10 code for Alzheimer’s dementia with behavioral disturbance is G30.9 + F02.811 or F02.818. The ICD-10 code for Alzheimer’s dementia unspecified is G30.9 + F02.80. The ICD-10 code for Alzheimer’s dementia with anxiety is G30.9 + F02.84. The ICD-10 code for early-onset Alzheimer’s dementia uses G30.0. The ICD-10 code for severe Alzheimer’s dementia and ICD-10 code for advanced alzheimer’s dementia use F02.C0. The ICD-10 code for dementia in Alzheimer’s disease, ICD-10 code for dementia Alzheimer’s type, ICD-10 code for Alzheimer’s disease with dementia, and ICD-10 code for Alzheimer’s dementia follow the same G30 + F02 pairing.

Lewy Body Dementia

The ICD-10 code for lewy body dementia is G31.83 plus an F02 code. Lewy body dementia presents with fluctuating cognition, visual hallucinations, and Parkinsonism.

Scenario	Etiology code	+ Manifestation code
Lewy body, no behavioral	G31.83	F02.80
Lewy body with behavioral	G31.83	F02.811 / F02.818
Lewy body, unspecified	G31.83	F02.80

The ICD-10 code for dementia with lewy bodies uses G31.83. The ICD-10 code for lewy body dementia unspecified is G31.83 + F02.80. The ICD-10 code for lewy body dementia with behavioral disturbance is G31.83 + F02.811 or F02.818. The ICD-10 code for lewy body dementia without behavioral disturbance is G31.83 + F02.80.

Frontotemporal Dementia

The ICD-10 code for frontotemporal dementia is G31.09 plus an F02 code. Frontotemporal dementia presents with early personality change, behavioral disinhibition, or progressive language impairment.

Scenario	Etiology code	+ Manifestation code
Frontotemporal, other	G31.09	F02.8x
Pick’s disease	G31.01	F02.8x
Frontal lobe dementia	G31.09	F02.8x

The ICD-10 code for frontal lobe dementia codes within the frontotemporal G31.0- series.

Parkinson’s Disease Dementia

The ICD-10 code for parkinson’s dementia uses a G20 Parkinson’s code plus an F02 code.

Scenario	Etiology code	+ Manifestation code
Parkinson’s disease with dementia	G20.x	F02.80
Parkinson’s dementia with behavioral	G20.x	F02.811 / F02.818

The ICD-10 code for parkinson’s disease with dementia, ICD-10 code for dementia due to parkinson’s disease, and ICD-10 code for parkinson’s with dementia sequence the Parkinson’s code first, then the F02 code. Select the specific FY2026 G20 sub-code that matches documented dyskinesia and motor fluctuation status.

Mixed Dementia

The ICD-10 code for mixed dementia requires coding each documented etiology.

Scenario	Codes
Mixed Alzheimer’s and vascular	G30.9 + F02.8x and F01.5x

The ICD-10 code for mixed alzheimer’s and vascular dementia reports both the Alzheimer’s combination and the vascular code.

Alcohol-Related Dementia

The ICD-10 code for alcohol induced dementia codes within the alcohol-use disorder series with the persisting-dementia character.

Scenario	Code	Description (FY2026)
Alcohol dependence with persisting dementia	F10.27	Alcoholic dementia, dependence
Alcohol use unspecified with persisting dementia	F10.97	Alcoholic dementia, use unspecified
Alcohol abuse with persisting dementia	F10.17	Dementia due to alcohol abuse
Alcohol dependence with amnestic disorder	F10.26	Korsakoff (amnestic), dependence

The ICD-10 code for alcoholic dementia uses F10.27 or F10.97. The ICD-10 code for dementia due to alcohol abuse uses F10.17. The ICD-10 code for Korsakoff dementia uses F10.26 when amnestic features predominate.

Senile, Progressive, and Stage-Descriptive Dementia

The ICD-10 code for senile dementia codes to F03.90 when no etiology is documented.

Descriptive term	Code	Note
Senile dementia	F03.90	Age-related onset, no distinct etiology
Progressive dementia	F03.90	Default unless etiology documented
Chronic dementia	F03.90	Default unless etiology documented
Baseline dementia	F03.90	Default unless etiology documented
Neurodegenerative dementia	Etiology + F02.8x	Code the specific neurodegenerative cause

The ICD-10 code for senile dementia follows the same F03.90 mapping. The PAA queries what the ICD-10-CM code is for senile dementia resolve to F03.90. The ICD-10 code for progressive dementia, ICD-10 code for chronic dementia, and ICD-10 code for baseline dementia default to F03.90 absent a documented etiology. The ICD-10 code for neurodegenerative dementia codes the specific cause. The ICD-10 code for dementia with cognitive impairment codes the dementia itself; mild cognitive impairment without dementia codes to G31.84.

Behavioral and Psychiatric Disturbance Codes (BPSD)

Behavioral and psychological symptoms of dementia (BPSD) occupy the column axis of each family table. The following table maps each behavioral feature to its sub-code character across the 3 families at unspecified severity.

Behavioral feature	F03 (unspecified)	F01 (vascular)	F02 (etiology-specific)
With agitation	F03.911	F01.511	F02.811
Other behavioral (wandering, sundowning, disinhibition)	F03.918	F01.518	F02.818
With psychotic disturbance (hallucinations, delusions, paranoia)	F03.92	F01.52	F02.82
With mood disturbance (depression, apathy)	F03.93	F01.53	F02.83
With anxiety	F03.94	F01.54	F02.84

The ICD-10 code for dementia with behavioral disturbance selects the column matching the documented symptom. The ICD-10 code for dementia with agitation and the ICD-10 code for agitation due to dementia use the agitation character (.x11). The ICD-10 code for dementia with sundowning uses other behavioral (.x18). The ICD-10 code for dementia with psychosis, the ICD-10 code for dementia with hallucinations, and the ICD-10 code for dementia with paranoia use the psychotic character (.x2).

The ICD-10 code for dementia with depression uses the mood character (.x3). The ICD-10 code for dementia with anxiety uses the anxiety character (.x4). The ICD-10 code for dementia with confusion codes the dementia plus disorientation (R41.0) when confusion is documented apart from acute delirium.

Delirium Superimposed on Dementia Codes

Delirium superimposed on dementia requires 2 codes: F05 for the delirium and the dementia code for the chronic baseline.

Scenario	Code 1	Code 2
Delirium superimposed on dementia	F05	Underlying dementia code
Dementia with delirium	F05	Underlying dementia code

The ICD-10 code for dementia with delirium, the ICD-10 code for delirium with dementia, and the ICD-10 code for delirium superimposed on dementia use F05 plus the dementia code. F05 codes the acute confusional state. The dementia code records the chronic baseline.

Related Codes: History, Memory Loss, and Cognitive Impairment

Family history, personal history, and isolated cognitive findings use distinct codes from the active dementia codes.

Scenario	Code	Note
Family history of dementia	Z81.8	Family history of other mental/behavioral disorders
Memory loss (no dementia)	R41.3	Other amnesia
Mild cognitive impairment (no dementia)	G31.84	Pre-dementia state
Age-related cognitive decline	R41.81	Not equivalent to dementia

The ICD-10 code for family history of dementia and family history of dementia unspecified is Z81.8 (Family history of other mental and behavioral disorders). For a personal history of dementia, clinical judgment is required because dementia is typically an active chronic condition rather than a resolved disease.

In most cases, the current dementia diagnosis should be coded instead of using a personal-history Z-code. When memory loss is a symptom of documented dementia, code the dementia diagnosis. Use R41.3 (Other amnesia) only when memory loss is documented without a dementia diagnosis.

CPT Codes for Dementia Assessment and Care

Dementia encounters bill with CPT codes for cognitive assessment, cognitive and neuropsychological testing, evaluation and management (E/M), and care management. The ICD-10 code reports the diagnosis. The CPT code reports the service. Clean billing pairs the correct ICD-10 diagnosis with the correct CPT service code.

CPT/HCPCS Code	Service	Typical use
99483	Cognitive assessment and care plan service	Comprehensive assessment plus written care plan; ~50 minutes; replaced legacy G0505
96116	Neurobehavioral status exam, first hour	Assessment of thinking, reasoning, judgment
96121	Neurobehavioral status exam, each additional hour	Add-on to 96116
96132	Neuropsychological testing evaluation, first hour	Professional interpretation and reporting
96133	Neuropsychological testing evaluation, each additional hour	Add-on to 96132
96136	Test administration, first 30 minutes	Technician or professional administration
96137	Test administration, each additional 30 minutes	Add-on to 96136
96125	Standardized cognitive performance testing	Per hour, with interpretation and report
99202–99215	Office/outpatient E/M	Standard dementia visits
G0438 / G0439	Annual Wellness Visit, initial / subsequent	Includes required detection of cognitive impairment
99490	Chronic care management, first 20 minutes	Non-face-to-face care coordination
99439	Chronic care management, each additional 20 minutes	Add-on to 99490
99491	Chronic care management by physician/QHP, first 30 minutes	Physician-provided CCM
99487 / 99489	Complex chronic care management	Higher-complexity coordination
99497 / 99498	Advance care planning	First 30 minutes / each additional 30 minutes
99366–99368	Medical team conference	Interdisciplinary care coordination

Cognitive assessment (99483) requires a standardized instrument and documented care-plan elements. Neuropsychological testing codes (96132–96137) separate professional evaluation from test administration. Chronic care management codes (99490–99491) capture non-face-to-face coordination for the chronic, progressive nature of dementia. The Annual Wellness Visit (G0438/G0439) requires detection of cognitive impairment, making cognitive screening a billable component of the preventive encounter.

CPT Modifiers for Dementia Billing

CPT modifiers report circumstances that change how a dementia service was performed without changing the code. Correct modifier use prevents denials when 2 services occur on the same day or through telehealth.

Modifier	Meaning	Dementia billing scenario
25	Significant, separately identifiable E/M on the same day as another service	E/M plus cognitive assessment (99483) or plus an Annual Wellness Visit same date
59	Distinct procedural service	Separate, non-overlapping testing services same day
95	Synchronous telehealth, audio-video	Cognitive assessment or E/M by telehealth
93	Synchronous telehealth, audio only	Audio-only dementia visit where payer permits
33	Preventive service	Preventive cognitive screening components
24	Unrelated E/M during a postoperative period	Dementia E/M unrelated to a recent procedure
52	Reduced services	Abbreviated testing or assessment

Modifier 25 carries the highest dementia-billing relevance, because dementia patients frequently receive an E/M service and a cognitive assessment on the same date. Appending modifier 25 to the E/M code prevents bundling denials. Modifier 95 governs telehealth delivery. Omitted or incorrect modifiers produce same-day bundling denials, the most common modifier-related rejection in cognitive care billing.

How Etiology and Manifestation Coding Works (the “Code First” Rule)

Manifestation codes require the underlying physiological condition sequenced first. F02 codes describe dementia as a manifestation of a disease classified elsewhere. The sequencing rule produces a 2-code or 3-code combination.

A patient with Alzheimer’s disease and documented agitation receives G30.9 first, then F02.811. The etiology code carries the disease. The F02 code carries the dementia manifestation and the behavioral feature. Submitting F02.811 without G30.9 triggers denial. This sequencing error is the single most common rejection driver for etiology-specific dementia claims.

Documentation Requirements That Support Dementia Codes

Dementia codes require provider documentation on 3 elements: etiology, severity, and behavioral features. The MEAT framework verifies documentation supports the code: Monitor, Evaluate, Assess, Treat.

Documentation that supports a specific dementia code includes 5 components: the named etiology (or explicit “unspecified”), the severity level, the behavioral or psychiatric feature, the functional impact on activities of daily living, and the clinical assessment establishing the diagnosis.

Case Scenario

A worked example demonstrates the difference. A note states: “Patient with Alzheimer’s disease, moderate stage, presenting with agitation and nighttime wandering, requiring increased caregiver supervision.” This note supports 3 axes: etiology (Alzheimer’s, G30.9), severity (moderate), and behavioral features (agitation). The note supports G30.9 + F02.B11, a far more specific and risk-accurate combination than F03.90 alone.

Common Dementia Coding Errors and Denial Triggers

Dementia coding produces 5 recurring errors that trigger denials and audit findings. These errors are highly systemic, which means they are completely preventable. To isolate these revenue leaks, dedicated neurology billing companies conduct continuous documentation audits and build clinical templates that capture severity-level drops and etiology shifts dynamically.

Assign unspecified codes when etiology is documented: A note documenting Alzheimer’s disease supports G30.9 + F02.8x, not F03.90.
Submit manifestation codes without the etiology code: F02.80 submitted without the underlying disease code rejects.
Submit non-billable parent codes: F03.9 and F01.5 are non-billable parent codes; claims require the billable child code.
Omit documented behavioral features: A note documenting agitation supports the .x11 character.
Retain stale codes as the condition progresses: Codes that remain at the mild tier after documented progression misstate severity and risk adjustment.

How Inaccurate Dementia Coding Causes Revenue Loss

Inaccurate dementia coding causes revenue loss through 4 mechanisms: outright claim denials, under-reimbursement from under-specified codes, lost risk-adjustment revenue, and forfeited cognitive-care reimbursement. Each mechanism drains revenue from practices providing dementia-related services.

Dementia coding errors reduce revenue in four ways. First, they cause denials, creating rework costs and lost reimbursement when claims are not resubmitted. Second, unspecified codes such as F03.90 can understate patient complexity and lower payment. Third, incomplete dementia coding may reduce HCC capture and Medicare Advantage risk-adjustment revenue. Finally, missed or under-documented dementia diagnoses can prevent reimbursement for cognitive assessment, chronic care management, and advanced care planning services.

Dementia Coding, HCC Risk Adjustment, and DRG Impact

Dementia codes map to Hierarchical Condition Categories (HCCs) that drive risk-adjustment factor (RAF) scores. RAF scores determine per-member-per-month payment for Medicare Advantage plans and risk-bearing organizations. A higher-acuity, accurately documented dementia code raises the RAF score and the associated capitated payment. Under-specified F03.90 coding, when more specific codes are supported, reduces RAF accuracy and understates patient acuity.

HCC capture requires annual recapture. Chronic conditions, including dementia reset each calendar year and require documentation in each measurement year to count toward the RAF score. A dementia diagnosis documented in 2025 does not carry into 2026 for risk-adjustment purposes without 2026 documentation.

Dementia codes affect inpatient DRG assignment. F02.80 groups within MS-DRG 884 (Organic disturbances and intellectual disability). Coding specificity connects directly to revenue integrity for health systems and risk-bearing organizations.

Conclusion

The ICD code 10 for dementia is built from 3 documented axes: etiology, severity, and behavioral features. F03.90 codes unspecified dementia without behavioral disturbance. F01.50 codes vascular dementia. F02.80 codes etiology-specific dementia as a manifestation requiring the underlying disease sequenced first. CPT codes report the services billed alongside the diagnosis, including cognitive assessment (99483) and chronic care management (99490–99491). Modifiers, including 25 and 95, report same-day and telehealth circumstances. Accurate coding supports clean claims, accurate HCC risk adjustment, and revenue integrity.

For practices managing high dementia volume across neurology, primary care, and geriatric panels, coding accuracy connects directly to denial rates and risk-adjustment capture. Specialized neurology billing services convert under-specified dementia documentation into accurate, audit-ready, fully reimbursed claims.