How to Use Diagnosis Codes to Support Hypertension, Diabetes and Anemia Claims

So much attention is paid to CPT codes in regard to billing and reimbursement that it sometimes seems the ICD-9 codes are little more than numerical window dressing on a claim form. However, getting claims paid requires the skillful use of both coding systems.

Think of it this way: CPT codes describe what you do, and ICD-9 codes describe why you do it.

While the amount of money an internist is reimbursed is linked to a claims CPT codes, the ICD-9 codes show the medical necessity of each service by establishing a diagnosis, symptom or complaint. One doesnt work without the other. To illustrate some of the broader concerns regarding ICD-9 coding as they pertain to internists, this article will look at three common disorders: hypertension, diabetes and anemia.

An Additional Digit May Be Required

The basic three-digit code for hypertension in the ICD-9 manual is 401 (essential hypertension), but its prefaced by a red stop-sign marker indicating that an additional digit is required. The choices include: 401.0 (malignant, severe high arterial blood pressure without apparent organic cause); 401.1 (benign, mild elevation in arterial blood pressure without apparent organic cause); and 401.9 (unspecified).

By far the most common symptom for hypertension is high blood pressure, but when an internist or coder checks under high blood pressure in the Index to Diseases section, he or she is referred to 401.9 in the Tabular List.

Thats telling the coder that high blood pressure is the same thing as unspecified hypertension, says Brink. Very often this would be the appropriate code because the patient may not have a history of high blood pressure and the internist feels theres insufficient evidence to warrant coding benign or malignant hypertension. But a lot of physicians wont use this code because they know that 401.9 sometimes doesnt get your claim paid.

Dont Be Too Quick to Code Hypertension

Scott Manaker, MD, a practicing internist at the Hospital of the University of Pennsylvania in Philadelphia, says hes careful not to make the diagnostic leap from high blood pressure to hypertension. One common error is whats called white coat hypertension. This is when the patient is abnormally anxious about seeing the doctor, says Manaker, whos also an adviser to the American College of Physicians/American Society of Internal Medicine panel on coding and reimbursement.

Manaker gives the example of a young man making his first visit to an internist. Hes shown [...]

- Published on 2001-06-01