Special Report: Hypertension Coding

Drug Coding Advisor: Knowledge leads to coding accuracy and better quality

Speak physicians’ hypertension language

(Editor’s note: This second part of a two-part DRG Coding Advisor series on hypertension coding offers suggestions about how coders can overcome obstacles through better understanding of hypertension diagnostics and through use of a hypertensive coding chart.)

If coders better understand hypertension diagnoses, they will be in a better position to ask doctors for more precise information and to code hypertension diagnoses more accurately, says a coding and medical expert.

"Coders need to be diagnosticians," says Kelly Butler, MD, CCS, owner of Dr. Coder & Associates of Murray, UT. "If they aren’t, then they can’t go to the doctor and say, I found these symptoms, and I wonder if this is what you meant to say.’" If coders can speak confidently with physicians in their own language, then physicians are less likely to brush coders’ concerns under the rug, Butler adds. Toward this goal, Butler offers coders this educational advice on hypertension:

1. Understand hypertensive disease.

Hypertension, which affects 50 million Americans, is blood pressure that is 140 or greater systolic and 90 or greater diastolic, Butler says. Of the 50 million Americans with hypertension, only 68% know their diagnosis, Butler adds. "Of those that know, only 53% with a hypertension diagnosis are receiving treatment, and of those receiving treatment, only 27% have their blood pressure under control."

Hypertension patients often won’t take their medication because they don’t feel sick until they do, Butler says.

"With this silent disease, there is progression, and it progresses to the point where it stops being silent and starts to scream," Butler explains. "And it screams by congestive heart failure, renal failure, and blindness."

2. Know the stages of hypertension.

The stages of hypertension are as follows:

  • Stage 1, mild hypertension: 140-159 systolic and 90-99 diastolic.
  • Stage 2, moderate hypertension: 160-179 systolic and 100-109 diastolic.
  • Stage 3, severe hypertension: 180 or greater systolic and 110 or greater diastolic.

Below hypertension, there is high normal blood pressure, which is 130-139 systolic and 85-89 diastolic. Blood pressure readings optimally are less than 120 systolic and less than 80 diastolic, although the normal range extends up to 129 systolic and 84 diastolic.

"When you hear mild,’ moderate,’ or severe,’ you know their blood pressure is out of control," Butler says. "But that’s all it says, because a coder cannot assign accelerated hypertension or malignant hypertension codes just based on a blood pressure reading."

Also, although hypertension coding permits a code for benign hypertension, that code is so rarely used that it should be a red flag to coders if the word benign’ appears in a physician’s notes, Butler says. (Click here, to see chart on hypertensive disease.)

3. Know the hypertensive emergencies.

Proper coding also depends on which of the following hypertensive emergencies apply:

  • Accelerated hypertension: This is a significant increase in blood pressure over previous levels and can entail vascular damage on funduscopic exam without papilledema.
  • Malignant hypertension: The systolic reading is greater than 200 and the diastolic is greater than 140. This diagnosis occurs in about 1% of hypertensives, and more often in men than women. It can result in encephalopathy or nephropathy, severe headache, vomiting, visual disturbances, transient paralysis, convulsions, stupor, coma, cerebral vascular spasm and edema, and presence of papilledema. It’s usually accompanied by retinal hemorrhages and exudates. Progressive renal failure can occur if malignant hypertension goes untreated.
  • Hypertensive encephalopathy: This also is a significant increase in blood pressure over previous levels. Its symptoms include headache, irritability, confusion, and altered mental status due to cerebrovascular spasm.
  • Hypertensive nephropathy: Again, this is a significant increase in blood pressure over previous levels, and it can result in hematuria, proteinuria, and progressive renal dysfunction due to arteriolar necrosis and intimal hyperplasia of the interlobular arteries.