Question: If a patient is diagnosed with both Parkinson's and dementia, can I assume the two conditions are related?
Florida Subscriber
Answer: It's not safe to make this assumption. No such instruction exists in the official coding guidelines.
When the physician confirms that the dementia is associated with Parkinson's, you can assign a code from the 294.1 subcategory (Dementia in conditions classified elsewhere). These codes are used to indicate the presence (294.11) or absence (294.10) of behavioral disturbances such as aggressive behavior, combative behavior, violent behavior or wandering off. The behavioral aspect of the dementia plays an important role in the treatment and long-term care of patients suffering from this condition.
Read the notes: Your ICD-9 manual instructs you to list the underlying condition first when reporting a code from the 294.1 category. So, if the link between the dementia and the Parkinson's disease is confirmed, you'll want to list the Parkinson's first.
Caution: Be sure to list 331.82 (Dementia with Parkinson's) rather than 332.0 (Parkinsonism or Parkinson's disease) for the Parkinson's disease if there is a causal link. Code 332.0 specifically excludes dementia with Parkinsonism.
If the link isn't documented and you suspect that your patient's dementia is due to Parkinson's, query the physician.