Alphabetic Index FY2027

F01.B18

Vascular dementia, moderate, with other behavioral disturbance

FY2027Chapter 5: Mental, Behavioral and Neurodevelopmental disorders/F01–F09 Mental disorders due to known physiological conditions

BillableComplete code, valid to report
Care settingsHome Health Primary · Behavioral HealthHospital CCIPF Primary · MS-DRG 884

F01.B18 (also written F01B18) is a billable ICD-10-CM diagnosis code for vascular dementia, moderate, with other behavioral disturbance. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 24 codes in category F01 (Vascular dementia). The Alphabetic Index lists it under 2 entries. Its coding notes include a Code first instruction, a Use additional code instruction and 1 Excludes2 entry.

Guidelines tip

From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.

Dementia codes depend on severity documented by the provider. If severity is not documented, the unspecified severity code is assigned. If severity progresses during an inpatient stay, one code is assigned for the highest level.

Guidelines I.C.5.dDementia: severityRead the official text

Code first

If the underlying condition listed here is present and known, sequence it first.

Inherited from F01 Vascular dementia
  • , if applicable, any causal condition

Use additional code

Add the listed code as a secondary code, if known.

This code
  • code, if applicable, to identify wandering in vascular dementia (Z91.83)

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Also from chapter/block level (1 note)
Inherited from Chapter 5 Mental, Behavioral and Neurodevelopmental disorders
  • symptoms, signs and abnormal clinical laboratory findings, not elsewhere classified (R00-R99)

Care settings

How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.

Home Health Primary

Accepted as the primary (principal) diagnosis on a home health claim. The Home Health Grouper assigns it to the Behavioral Health clinical group.

Source: CMS Home Health Grouper Software v07.2.26, effective October 1, 2026

Hospital CC

Counts as a complication or comorbidity (CC) when reported as a secondary diagnosis on an inpatient claim. It does not count when the principal diagnosis is one of the 20 codes in its exclusion list. Some MS-DRGs also ignore a CC or MCC that defines the DRG.

Source: CMS MS-DRG Definitions Manual v44, effective October 1, 2026, Appendix C

IPF Primary

IPF MS-DRG adjustment. A principal diagnosis of this code groups to this MS-DRG:

MS-DRGDescriptionFactor
884Organic disturbances & intellectual disabilities1.08
A principal diagnosis that groups to none of the 19 designated MS-DRGs gets no MS-DRG adjustment. Otherwise the claim still receives the federal per diem base rate and the other adjustments.

Source: CMS IPF PPS FY 2027 final rule (CMS-1847-F), Addendum A; code lists from the CMS MS-DRG Definitions Manual v44; effective for discharges on or after October 1, 2026

Includes

Further defines or gives examples of the content of the category.

Inherited from F01 Vascular dementia
  • arteriosclerotic dementia
  • major neurocognitive disorder due to vascular disease
  • multi-infarct dementia
Also from chapter/block level (1 note)
Inherited from Chapter 5 Mental, Behavioral and Neurodevelopmental disorders
  • disorders of psychological development

Inclusion terms

Conditions classified to this code.

This code
  • Major neurocognitive disorder due to vascular disease, moderate, with behavioral disturbances such as sleep disturbance, social disinhibition, or sexual disinhibition
  • Vascular dementia, moderate, with behavioral disturbances such as sleep disturbance, social disinhibition, or sexual disinhibition

Notes

Also from chapter/block level (1 note)
Inherited from F01–F09 Mental disorders due to known physiological conditions
  • This block comprises a range of mental disorders grouped together on the basis of their having in common a demonstrable etiology in cerebral disease, brain injury, or other insult leading to cerebral dysfunction. The dysfunction may be primary, as in diseases, injuries, and insults that affect the brain directly and selectively; or secondary, as in systemic diseases and disorders that attack the brain only as one of the multiple organs or systems of the body that are involved.

Alphabetic Index terms

Terms the official Alphabetic Index lists for this code. 2 entries