Primary Care Coding Alert

Question: Dementia is a symptom of Alzheimer’s, so does that mean I can’t code them together?

Arkansas Subscriber

Answer: The answer to this will come down to documentation. Here’s why.

First, let’s review the ICD-10 guidelines you’re alluding to, which are 1.B.4-6. They state the following: “Codes that describe symptoms and signs, as opposed to diagnoses, are acceptable for reporting purposes when a related definitive diagnosis has not been established (confirmed) by the provider… Signs and symptoms that are associated routinely with a disease process should not be assigned as additional codes, unless otherwise instructed by the classification. Additional signs and symptoms that may not be associated routinely with a disease process should be coded when present.”

Also consider that the Centers for Disease Control and Prevention (CDC) says that dementia is not a disease, but rather a general term to describe the inability to remember. So, it’s easy to see why you might wonder whether to code dementia, the most commonly recognized symptom of Alzheimer’s disease, with the disease itself.

However, dementia is often a manifestation of Alzheimer’s, and ICD-10 Official Guideline 1.A.13 addresses the rule for situations like this. Basically stated, it requires you to sequence the underlying condition first “if applicable, followed by the manifestation.” This refers to the “Code first,” “Use additional code,” and “In diseases classified elsewhere” notes you see in the tabular section of ICD-10. “Use additional code” notes typically appear with is the code for an underlying condition and reflect the requirement that the underlying condition be sequenced first followed by manifestations. How you would code this specifically depends on how it’s documented.

Suppose documentation shows a patient has dementia due to Alzheimer’s disease and is displaying agitation. If you search for the Alzheimer’s disease codes (G30.-) first, you’ll find a “Use additional code” note that will direct you, if applicable, to codes for various conditions, including dementia with behavioral disturbance (F02.81-, F02.A1-, F02.B1-, F02.C1-). For the example, the relevant code is F02.811 (Dementia in other diseases classified elsewhere, unspecified severity, with agitation).

Note: If you started by finding F02.811, you would see a symbol by that code showing that it is a manifestation code. Also, a note with F02.- tells you to “Code first the underlying physiological condition,” such as G30.- (Alzheimer’s disease).

The tricky part here is interpreting what the doctor wrote down. If it’s clear that the expert’s opinion is that the dementia is due to the Alzheimer’s, then you should report the dementia as a manifestation, as described above. However, if you find yourself trying to stretch your clinical understanding to meet the provider’s vague notes, that is likely a situation that calls for a query. It can be hard to know where to draw that line, but when the documentation isn’t clear, seek clarification.