Dementia ICD-10-CM codes

Since FY2023, every dementia code in F01 (vascular), F02 (in other diseases classified elsewhere), and F03 (unspecified) carries two axes. The fourth character is severity: 5, 8, or 9 for unspecified severity depending on the category, A for mild, B for moderate, and C for severe. The fifth and sixth characters report the disturbance: 0 without any disturbance, 11 with agitation, 18 with other behavioral disturbance, 2 with psychotic disturbance, 3 with mood disturbance, and 4 with anxiety. F03.90 is unspecified dementia, unspecified severity, without behavioral, psychotic, mood, or anxiety disturbance.

Severity must come from provider documentation; the guidelines do not allow assigning it from a screening score alone. If the severity changes during an admission, report the highest documented severity. Agitation includes restlessness, verbal or physical aggression, and combativeness; sundowning, wandering, and sleep disturbance count as other behavioral disturbance (the 18 codes). Add Z91.83 (wandering in diseases classified elsewhere) when wandering is documented.

Dementia with a known cause is coded to F02.- with the etiology first: G30.- for Alzheimer's disease, G20.- for Parkinson's disease, G31.83 for Lewy body disease, and G31.09 for frontotemporal dementia. Vascular dementia (F01.-) does not need a separate cerebrovascular code unless the provider links a specific event. Never report F03 together with F01 or F02.

Delirium superimposed on dementia is reported with F05 in addition to the dementia code. Mild cognitive impairment (G31.84) and age-related cognitive decline (R41.81) are not dementia and should not be coded to F03. If the provider documents both MCI and dementia, query, since the two are mutually exclusive.