Psychiatry Coding & Reimbursement Alert

Question: Our psychiatrist recently diagnosed a patient with dementia. The patient has a history of Alzheimer’s disease. What code(s) should I report for the diagnosis of the patient?

Illinois Subscriber

Answer: When reporting a case of dementia with an underlying condition (in this case, Alzheimer’s disease), you will have to report the dementia with 294.1x. You will have to use a fifth digit expansion to this ICD-9 code depending on whether or not there is any behavioral disturbance present:

• 294.10 (Dementia in conditions classified elsewhere without behavioral disturbance)
• 294.11 (…with behavioral disturbance)

You also have to report the Alzheimer’s disease with the ICD-9 code, 331.0 (Alzheimer’s disease). ICD-9 directs that when reporting 294.1x, you should code first any underlying physical condition, such as Alzheimer’s disease. Therefore, you should report 331.0 first followed by 294.1x. If the patient has other pertinent diagnoses, such as a history of wandering, you will have to additionally report those circumstances with other codes (e.g. V40.31, Wandering in diseases classified elsewhere).

ICD-10: When you begin using ICD-10 codes, again based on the presence or absence of behavioral issues, you have two options to report dementia in Alzheimer’s disease:

• F02.80 (Dementia in other diseases classified elsewhere without behavioral disturbance)
• F02.81 (…with behavioral disturbance)

You will have to report the Alzheimer’s disease with G30.- using the appropriate 4th digit expansion to identify the onset of the disease. As in ICD-9, ICD-10 directs you to report the underlying physiological condition first, so you would report G30.- first, followed by F02.8-. Report Z91.83 (Wandering in diseases classified elsewhere) if wandering in dementia has been identified.