We had some questions from students regarding hypertension. They were confused about hypertension and CKD (Chronic Kidney Disease), and hypertension and heart disease. We talk extensively about this in the PBC Course so that is where we are going to cover it the most.

I10 Is the First Code You Learn in ICD-10

So we know that hypertension is coded I10. In the past, it was coded as 401.9. It is probably the first diagnosis code that you’re going to learn in medical coding because so many people have hypertension. With it being I10 in ICD-10, it’s also very easy to remember, right? So we just laugh with it and say, “Well, I10 is the first code you learn in I-10.

In the past, we had more codes for different types of hypertension. To clarify, I’m not talking about pulmonary hypertension…that is completely different since it affects the pulmonary system, not the heart.

So, with hypertension of the heart, we have benign hypertension, malignant, essential, and other hypertensions. With ICD-10, instead of having multiple codes for hypertension, they give you one code. So if you go and look in your manual for I10, you’ll notice that there is a parenthetical there, not brackets but a parenthesis that tells you everything that is included in the description of I10. So I’m in H’s, not I’m going to I10. So there’s I6. There it is. So we have I10 is essential primary hypertension, and it includes arterial, benign, essential, malignant, primary, and systemic. All of those are one code now, I10.

Hypertension and Heart Disease vs Hypertension and CKD (Chronic Kidney Disease)

But what about hypertension and heart disease, and hypertension and CKD (Chronic Kidney Disease)? The key to coding these is to understand the grammar that goes along with it. The word “and” means it’s not connected, just like we did diabetes. Diabetes and neuropathy, and diabetic neuropathy, or diabetes with neuropathy. Diabetic neuropathy means it’s diabetic neuropathy. Diabetes with neuropathy means it’s diabetic neuropathy. Diabetes and neuropathy means you code for diabetes and you code separately for neuropathy. So there are two separate codes used because of the grammer. The keyword is “and” and “with.”

With hypertension and CKD, you always put those together. It does not matter if it says “and” or “with.” There’s a causal relationship (that’s what they call it) and you will always code them together. So, you would code hypertensive CKD. So whenever you have hypertension and CKD in the diagnosis, it is no longer hypertension I10. It becomes hypertensive CKD which is I12.

So, know that CKD and hypertension are together no matter what the verbiage. The reason for that is because as far as the disease process goes, when a person has CKD, they most always have hypertension. When a person has hypertension, it affects the kidneys. It’s hard on the kidneys when you have chronic hypertension. But if you have CKD, it’s almost guaranteed that you have hypertension. Because of that, we know that in the disease process, the coding just tells you there is a causal relationship, they will always be together and you will, I guarantee it, be tested on that.  So to reiterate, “hypertension and CKD” or “hypertension with CKD” is I12. That’s where you start although there are other things you need to code with that…but that’s the beginning.

What About Hypertension and Heart Disease?

That is going to be if it’s “and”, it’s not a causal relationship. It’s just like the diabetes. It’s like “diabetes and neuropathy”; “hypertension and heart disease”. You would code out I10 and whatever your heart disease code which is an I50 code.  So you have two (2) codes: hypertension and heart disease.

“And” and “With” Are the Main Keywords

The big lesson here is to be very aware of “and” and “with” when dealing with these codes. You’re going to be tested on this, and the best way they do that is they’re going to say hypertension and heart disease, and they’re going to give you a choice of I10 and I50 codes, and they’re going to put on B, they’re going to have I11 and I50 codes. Then they may mix them up and put I50. They’ll do other things. But the key is that if it says “and,” it’s an I10. If it says “with,” it’s an I11. The hypertension changes.

What if They Have Both Hypertensive Heart Disease and CKD?

This one is easy so don’t let that frighten you. You know that if you have hypertension and CKD, it will always be I12, right? If you have hypertension “with”, it’s going to be I11 or “and,” but they give you a code for all of those. So that would be I13. So go look in your ICD-10 manual and bring up I13 in the tabular. Then of course, you’re going to code for it with an I50 code and continue the coding process as needed.

What Is They Have Hypertension and Heart Disease?

What are you going to code? You’re going to code I12 and you’re going to code for the hypertension and CKD which is I12, then you’re also going to code for the heart disease which is going to be the I50 because there’s no causal relationship there. For the CKD, without confusing you further, you have to follow the guidelines here because whenever you have CKD, they’re going to give you a stage. So this isn’t the only thing you’re coding. You would also include the stage and follow additional coding guidelines. The code will not just be I50 because whenever you code CKD, you’re going to code the stage (I, II, III, IV) or if it’s end-stage renal disease.

For the record, the stage codes are N18.1, N18.2, N18.3. So N18.1 is CKD stage I, .2 is CKD stage II. So follow the last digits to find the stage. You will find this in nephrology, kidneys, neph. However, you don’t have to have it memorized. Just understand that these are the basics of how hypertension changes the code depending on if they have CKD or if they have heart disease or both associated with hypertension.

Remember, this will most likely appear in the CPC exam and it won’t be simple question-asking either. They’re going to go in-depth with the case most likely. For example, “Mr. Jones came in today, his hypertension is doing well, but he continues on his medication. He is moved from CKD stage I to II”, etc. So then you have to think, “Wait a minute…he has hypertension. He has CKD. I need to remember this article!”

Hopefully this article has helped clear up how to code hypertension and CKD (Chronic Kidney Disease), and hypertension and heart disease. We have YouTube videos on these topics as well. If you need more education, be sure to visit, subscribe and “like” any of the videos that you see. If you have any other questions, please post them in the comments below.