Primary Care Coding Alert

Question: A payer has denied an F01.50 diagnosis code as an invalid primary diagnosis on a claim, but I don’t see a note saying the code cannot be a primary or first-listed diagnosis. What am I doing wrong?

AAPC Forum Participant

Answer: Even though you have no guidelines telling you that F01.50 (Vascular dementia without behavioral disturbance) cannot be a primary or first-listed diagnosis, there is a note accompanying the F01 (Vascular dementia) codes telling you to “code first the underlying physiological condition or sequelae of cerebrovascular disease.”

A second note accompanying the codes that describes the etiology of the conditions elaborates why. Vascular dementia is “a result of infarction of the brain due to vascular disease, including hypertensive cerebrovascular disease.” So, because the vascular dementia has an underlying cause, and because the cause, and not the dementia itself, is the treatable condition, the cause itself must be listed first as that is what your provider will be treating.

That means you should code the condition’s cause, such as stroke or narrowed or damaged blood vessels, first and the F01.50 second.