Coding Hypertension with Heart Disease and CKD: I10, I11, I12, I13

The classification presumes the link

In the Alphabetic Index, hypertension is linked to heart involvement and to kidney involvement by the word with. The guidelines treat that word as a presumed causal relationship. You code the conditions as related even when the provider never writes hypertensive heart disease or CKD due to hypertension. The only exception is documentation that clearly states the conditions are unrelated.

That presumption does not extend to everything. For conditions the classification does not link with a relational term, the provider has to document the connection before you can code them as related.

Choose the category by what is present

• I10, Essential (primary) hypertension: hypertension with no heart condition or chronic kidney disease that the classification links to it, or with those conditions when the provider documents them as unrelated.
• I11, Hypertensive heart disease: hypertension with heart failure (I50.-) or with one of the heart conditions the guideline lists, such as I51.4, I51.89, or I51.9. I11.0 includes heart failure; I11.9 does not.
• I12, Hypertensive chronic kidney disease: hypertension with a condition classifiable to N18. I12.9 covers stage 1 through 4 or unspecified CKD; I12.0 covers stage 5 or end stage renal disease.
• I13, Hypertensive heart and chronic kidney disease: hypertension with both heart disease and CKD. The fifth and sixth characters capture whether heart failure is present and the CKD stage range.

Hypertension combination code table

Find the row that matches every condition documented for the encounter. A code ending in a hyphen, such as I50.-, means you still choose the complete code that identifies the type of heart failure. For example, hypertension with chronic diastolic heart failure and chronic kidney disease stage 3b is reported as I13.0 with I50.32 and N18.32.

The additional codes are required, not optional

The combination code names the relationship, but it does not carry every detail. With I11, add a code from I50 to identify the type of heart failure, or from I51 for the heart condition, when the guideline calls for it. With I12 or I13, add a code from N18 to identify the CKD stage. With I13 and heart failure, add the I50 code as well.

Heart conditions classified to I51.5, Myocardial degeneration, or I51.7, Cardiomegaly, are the exception: I11 is assigned and no additional code identifies the heart condition.

Do not split I13 into I11 and I12

When a patient has hypertension, heart disease, and chronic kidney disease, the Includes note at I13 means the conditions from I11 and I12 are captured together. Report a single I13 code with its required additional codes. Reporting I11 and I12 side by side for the same encounter misstates the classification.

When diabetes is also involved

Diabetic chronic kidney disease has its own combination code, such as E11.22 for type 2 diabetes. A patient with diabetes, hypertension, and CKD can support both relationships at once: the diabetes combination code and the hypertensive CKD code, followed by a single N18 code for the stage. Sequence them by the reason for the encounter.

Controlled, uncontrolled, and elevated readings

• Controlled or uncontrolled hypertension still maps to the hypertensive disease categories. Neither word changes the category on its own.
• An elevated blood pressure reading without an established diagnosis of hypertension is R03.0, not I10.
• Hypertensive urgency or emergency is coded to I16, with a code for any identified hypertensive disease as well.

Questions coders ask

Do I need the provider to write hypertensive CKD to use I12?

No. The classification presumes the relationship between hypertension and chronic kidney disease. Assign I12 unless the documentation clearly states the CKD is not related to the hypertension.

Can I report I11.0 and I12.9 together?

No. When hypertension, heart disease, and chronic kidney disease are all present, report a code from I13 instead of codes from I11 and I12.

Is the CKD stage code still needed with I12 or I13?

Yes. Add the N18 code that identifies the stage. If both a CKD stage and end stage renal disease are documented, assign N18.6 only.

Is uncontrolled hypertension a different code?

No. Controlled and uncontrolled hypertension are both coded to the appropriate category in I10 to I15. The word does not create a separate code.

Practice these rules

• Home Readings and Kidney Function Review
• Renal Laboratory Follow-Up
• Cardiac Medication Follow-Up
• Chronic Condition Follow-Up With Renal Review
• Home Readings and Medication Review

Browse the full 30-case library

Keep learning

• Combination Codes: One Code That Says It All
• Type 2 Diabetes Coding with Insulin and Oral Medications: E11 and Z79
• How to Sequence ICD-10-CM Diagnosis Codes

Sources

• ICD-10-CM Official Guidelines for Coding and Reporting FY 2027

  Section I.C.9.a, Hypertension

• ICD-10-CM Official Guidelines for Coding and Reporting FY 2027

  Section I.C.9.a.1, Hypertension with Heart Disease

• ICD-10-CM Official Guidelines for Coding and Reporting FY 2027

  Section I.C.9.a.2, Hypertensive Chronic Kidney Disease

• ICD-10-CM Official Guidelines for Coding and Reporting FY 2027

  Section I.C.9.a.3, Hypertensive Heart and Chronic Kidney Disease

• ICD-10-CM Official Guidelines for Coding and Reporting FY 2027

  Section I.C.9.a.7 to I.C.9.a.10, Transient, controlled, uncontrolled, and crisis

• ICD-10-CM Official Guidelines for Coding and Reporting FY 2027

  Section I.C.14.a.1, Stages of chronic kidney disease

• FY 2027 ICD-10-CM Tabular List and Alphabetic Index

  Tabular List, codes I11.0, I12.0, I12.9, I13.0, I13.10, I13.11, I13.2

• FY 2027 ICD-10-CM Code Descriptions in Tabular Order

  Codes I10, I11.0, I11.9, I12.0, I12.9, I13.0, I13.10, I13.11, I13.2, I50.32, N18.32, N18.5, N18.6, E11.22, R03.0