Psychiatry Coding & Reimbursement Alert

Question: Our psychiatrist recently assessed a 55-year-old male patient and noted sundowning in the patient notes. Is there a specific code that I can use to report sundowning. What is the correct diagnosis for sundowning? 

Colorado Subscriber

Answer: Sundowning is a term that is used to describe agitation and confusion that some people experience during the evening. It is usually one of the symptoms that you might notice in patients suffering from Alzheimer’s. Scientists do say, however, that sundowning is more than just dementia. Sundowning really is delirium most often superimposed on dementia.

There is no specific ICD-9 code for sundowning — probably partly because scientists have not yet completely determined what causes the syndrome. Because of this, choose your diagnosis based on the patient’s specific brain disease. 

Example: Report 331.0 (Alzheimer’s disease) for diagnosed Alzheimer’s patient, and use an additional code to report dementia or delirium, where appropriate. For dementia secondary to Alzheimer’s, your coding options include 294.10 (Dementia in conditions classified elsewhere without behavioral disturbance) and 294.11 (Dementia in conditions classified elsewhere with behavioral disturbance). For delirium secondary to Alzheimer’s, consider 293.0 (Delirium due to conditions classified elsewhere) or 293.89 (Other specified transient mental disorders due to conditions classified elsewhere; other). Code 293.0 is generally intended for acute delirium, whereas code 293.89 is associated with chronic delirium.

If the patient does not have Alzheimer’s and is diagnosed only with dementia, then consider a code from 290.xx (Dementias) family. As above, if delirium is superimposed on (i.e., secondary to) the dementia, consider adding 293.0 or 293.89 as a second diagnosis.

Finally, if the "sundowning" is symptomatic with no definitive diagnosis of either Alzheimer’s or dementia, your primary option would be 780.09 (Alteration of consciousness; other), which is in the symptoms section of ICD-9 and does not represent a definitive diagnosis. 

Talk with your psychiatrist to determine the most appropriate diagnoses for each patient.