F03.918
Unspecified dementia, unspecified severity, with other behavioral disturbance
F03.918 (also written F03918) is a billable ICD-10-CM diagnosis code for unspecified dementia, unspecified severity, 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 F03 (Unspecified dementia). The Alphabetic Index lists it under 2 entries. Its coding notes include a Use additional code instruction and 3 Excludes2 entries.
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.
Use additional code
Add the listed code as a secondary code, if known.
- code, if applicable, to identify wandering in unspecified 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)
- 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, 2026Hospice: not accepted as primary
Not accepted as the principal diagnosis on a hospice claim (bill types 081x and 082x). The Integrated OCE returns an edit for this code.
Reason: Supplementary or additional code, not allowed as principal diagnosis.
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 CIPF Primary
IPF MS-DRG adjustment. A principal diagnosis of this code groups to this MS-DRG:
| MS-DRG | Description | Factor |
|---|---|---|
| 884 | Organic disturbances & intellectual disabilities | 1.08 |
Includes
Further defines or gives examples of the content of the category.
Also from chapter/block level (1 note)
- disorders of psychological development
Inclusion terms
Conditions classified to this code.
- Unspecified dementia, unspecified severity, with behavioral disturbances such as sleep disturbance, social disinhibition, or sexual disinhibition
Notes
Also from chapter/block level (1 note)
- 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
- Dementia (degenerative (primary)) (persisting) (unspecified severity) (without behavioral disturbance, psychotic disturbance, mood disturbance, and anxiety), with, behavioral disturbances (sexual disinhibition) (sleep disturbance) (social disinhibition)
- Dementia (degenerative (primary)) (persisting) (unspecified severity) (without behavioral disturbance, psychotic disturbance, mood disturbance, and anxiety), with, behavioral disturbances (sexual disinhibition) (sleep disturbance) (social disinhibition), specified NEC