Dementia
The ICD-10-CM classifies dementia (categories F01, F02, and F03) on the basis of the etiology and severity (unspecified, mild, moderate or severe).
Selection of the appropriate severity level requires the provider’s clinical judgment and codes should be assigned only on the basis of provider documentation (as defined in the Official Guidelines for Coding and Reporting), unless otherwise instructed by the classification. If the documentation does not provide information about the severity of the dementia, assign the appropriate code for unspecified severity.
If a patient is admitted to an inpatient acute care hospital or other inpatient facility setting with dementia at one severity level and it progresses to a higher severity level, assign one code for the highest severity level reported during the stay.
ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026 (effective October 1, 2025). Published by CMS and NCHS. Reproduced for reference — always verify against the official CMS release.