October 15, 2007
Alzheimer’s disease (ICD-9-CM code 331.0) is a progressive, degenerative brain disease that damages and kills brain cells. It causes a steady decline in memory and mental abilities severe enough to interfere with daily functioning. The disease can progress from mild to moderate to severe and then to profound impairment. Although there is no cure, medications are available that help improve the quality of life and lessen the signs and symptoms.
The common symptoms of Alzheimer’s disease include the following:
• increasing and persistent forgetfulness;
• difficulty with abstract thinking;
• difficulty with finding the right word;
• loss of judgment;
• problems with performing familiar tasks;
• failure to recognize familiar people or places; and
• personality changes.
Alzheimer’s disease is difficult to diagnose because there are no tests available to confirm its presence. In fact, Alzheimer’s disease can only be confirmed at autopsy when amyloid plaques and neurofibrillary tangles are found in the brain tissue. Instead, it is diagnosed by a process of elimination. Physicians use the following to aid in the diagnosis of Alzheimer’s disease:
• medical history;
• blood and urine tests to rule out other potential causes;
• mental status evaluation;
• neuropsychological testing; and
• brain scans such as CT, MRI, and positron emission tomography.
Dementia is a progressive impairment of brain function so severe that it affects a person’s ability to function at his or her usual level. Alzheimer’s disease is the most common cause of dementia. Alzheimer’s dementia requires two ICD-9-CM codes. Code 331.0 is sequenced first followed by code 294.1x. The fifth digit code assignment depends on whether the dementia is with or without behavioral disturbances such as aggressive behavior, combative behavior, violent behavior, or wandering off.
Other diseases that can cause dementia include the following:
• Parkinson’s disease (332.0);
• Jakob-Creutzfeldt (046.1);
• Huntington’s chorea (333.4);
• Multiple sclerosis (340); and
• AIDS (042).
Code 294.1x is assigned as an additional code with the above conditions to identify the associated dementia.
Among the medications that can slow the progression of the disease and lessen the symptoms is cholinesterase inhibitors, which improve the level of neurotransmitters in the brain and include the following:
• donepezil (Aricept);
• rivastigmine (Exelon); and
• galantamine (Razadyne)
Another medication, memantine (Namenda), protects brain cells from damage and slows the loss of daily living skills. This medication has been approved to treat moderate and severe stages of Alzheimer’s disease.
Physicians may also prescribe medications to improve behavioral problems of Alzheimer’s disease such as sleeplessness, wandering, anxiety, agitation, and depression.
Coding and sequencing for Alzheimer’s dementia are dependent on the physician documentation in the medical record and application of the Official Coding Guidelines for inpatient care. Also, use specific AHA Coding Clinic for ICD-9-CM and American Medical Association CPT Assistant references to ensure complete and accurate coding.
— This information was prepared by Audrey Howard, RHIA, of 3M Consulting Services. 3M Consulting Services is a business of 3M Health Information Systems, a supplier of coding and classification systems to nearly 5,000 healthcare providers. The company and its representatives do not assume any responsibility for reimbursement decisions or claims denials made by providers or payers as the result of the misuse of this coding information. More information about 3M Health Information Systems is available at www.3mhis.com or by calling 800-367-2447.