Home Health ICD-9/ICD-10 Alert

Conquering Case Mix:

Time to Give Your Hypertension Coding a Check-Up

Take care not to get caught in this upcoding trap.

It's official -- as of the first of the year, you'll no longer earn case mix points for two common hypertension codes. But that doesn't necessarily mean your agency will take a reimbursement hit. Other comorbidities and more specific coding may soften the blow.

The final word: While the Centers for Medicare & Medicaid Services had been considering this change for some time, the PPS final rule released Oct. 31, 2011 put it into effect. "Beginning with M0090 dates of January 1, 2012, 401.1 Benign essential hypertension codes and 401.9 Unspecified essential hypertension are removed from the HH PPS case-mix system. Specifically, 401.1 and 401.9 diagnosis codes will no longer result in additional points when computing the HIPPS codes," CMS said in announcing the latest update to the home health case mix grouper software.

Lack of Documentation Lead to Case Mix Change

CMS eliminated case mix points for codes 401.1 and 401.9 because agencies were using them inappropriately, says consultant Lynda Laff with Laff Associates in Hilton Head Island, S.C. Home health agencies often used these HTN case mix codes as a primary diagnosis at start of care and in the second, third, or subsequent recertifications as a means to both garner three case mix points and/or to keep the patient on services, Laff says.

Problem: When hypertension is the primary diagnosis, once your patient's blood pressure is stable and you've provided teaching on any new hypertension medication, it's expected you'll work toward discharge, says Jennifer Warfield, BSN, HCS-D, COS-C, education director with PPS Plus Software in Biloxi, Miss.

And during medical review, there is often no documentation to support the need for skilled services related to the hypertension diagnosis for these patients, Laff says.

CMS statistics show that patients with hypertension were getting fewer visits than those without hypertension, which contradicts the reason for case mix status, notes Lisa Selman-Holman, JD, BSN, RN, HCS-D, COS-C, HCS-O, consultant and principal of Selman-Holman & Associates and CoDR -- Coding Done Right in Denton, Texas. Diagnoses with case mix status indicate that the patient needs more care because of that diagnosis.

Are You Coding Correctly for Hypertension?

Don't change the codes you use for hypertension unless you have been have been listing one of the 401.x codes in error, says Selman-Holman. "Changing the codes just to get points is upcoding and we certainly do not want to prove CMS correct about case mix creep. You can be sure that they will be watching for trends in hypertension coding as a result of the case mix change," she says.

You can continue to code hypertension if it is a diagnosis that your agency will be managing and addressing in the plan of care and visit notes, Laff says. Just make sure that you are coding correctly and that you continue to include hypertension where it is appropriate when the patient actually has HTN as a comorbidity, she says.

While the 401.1 and 401.9 hypertension codes no longer earn case mix points, there are still case mix points to be earned from the combination hypertension codes 402.x (Hypertensive heart disease), 403.x (Hypertensive renal disease) and 404.x (Hypertensive heart and renal disease). But these diagnoses must be validated by the physician or designee, Laff cautions.

Caution: Even though 401.0 (Malignant essential hypertension) remains case mix, its use should be rare in the home care setting, Selman-Holman says. Malignant hypertension is most often treated in the acute facility, although there are a few of these patients at home. You may only code malignant hypertension if the physician specifically documents "malignant." No other adjective, such as "uncontrolled" applies, she says.

Know the Assumption Rules

For patients who do have confirmed hypertension and chronic kidney disease or heart disease diagnoses, there is a coding rule quirk of which you must be aware. You can presume a relationship between chronic kidney disease and hypertension, Selman-Holman says. So you can look to the 403.x codes when your patient has hypertension with chronic kidney disease (585) or renal sclerosis (587).

But you can't presume a relationship between heart disease and hypertension. The physician must either state that there is a link (e.g., heart failure due to hypertension) or imply the relationship (e.g., hypertensive heart disease) before you can report a 402.x or 404.x code, Selman-Holman says. Heart conditions with hypertension are not automatically coded as hypertensive heart disease with a 402.x category code.

Bottom line: Clinicians and coders should make sure they are educated on the proper use of codes 402.x and 403.x codes, Laff says. And remember, these codes require a fifth digit.

See the Silver Lining

The loss of case mix points for hypertension diagnoses may seem like a blow at first, but don't despair, says Selman-Holman. "Even if you don't earn points with the hypertension codes, think how many of your patients with 401 codes also have codes from the 414.x category (Coronary atherosclerosis and chronic ischemia), 410.x (Acute myocardial infarction) and 428.x (Heart failure). Those codes are case mix, too, so you will not be losing any points," Selman-Holman points out.