Hypertension "with" ICD-10 Coding
When assigning diagnosis codes for hypertension (HTN), there is an presumed causal relationship between hypertension and heart involvement, and between hypertension and kidney involvement. The ICD-10-CM Official Guidelines for Coding and Reporting (I.C.9) instruct, “These conditions should be coded as related even in the absence of provider documentation explicitly linking them, unless the documentation clearly states the conditions are unrelated.” The Guidelines further specify:
Hypertension with Heart Disease: Hypertension with heart conditions classified to I50.- or I51.4- I51.9, should be assigned to a code from category I11, Hypertensive heart disease. An additional code from category I50, Heart failure, should be reported to identify the type of heart failure in those patients with heart failure. If the provider has specifically documented a different cause, the same heart conditions (I50.-, I51.4-I51.9) with hypertension are coded separately. These should be sequenced according to the circumstances of the admission/encounter.
For example, the provider documents exacerbated chronic heart failure (CHF) and HTN. Report I11.0 Hypertensive heart disease with heart failure and I50.9 Heart failure, unspecified.
Hypertensive Chronic Kidney Disease: Codes from category I12, Hypertensive chronic kidney disease, should be assigned when both hypertension and a condition classifiable to category N18, Chronic kidney disease (CKD), are present. CKD should not be coded as hypertensive if the physician has specifically documented a different cause. The appropriate code from category N18 should be used as a secondary code with a code from category I12 to identify the stage of chronic kidney disease.
If a patient has hypertensive chronic kidney disease and acute renal failure, an additional code for the acute renal failure is required.
For example, the provider documents HTN and stage III kidney disease. Report I12.9 Hypertensive chronic kidney disease with stage 1 through stage 4 chronic kidney disease, or unspecified chronic kidney disease and N18.3 Chronic kidney disease, stage 3 (moderate).
Hypertensive Heart and Chronic Kidney Disease: The codes in category I13, Hypertensive heart and chronic kidney disease, are combination codes that include hypertension, heart disease and chronic kidney disease, and should be used when there is hypertension with both heart and kidney involvement.
If heart failure is present, an additional code from category I50 should be reported to identify the type of heart failure. The appropriate code from category N18, Chronic kidney disease, should be used as a secondary code with a code from category I13 to classify the stage of chronic kidney disease.
For example, the provider documents HTN, CHG, and stage III kidney disease. Report I13.0 Hypertensive heart and chronic kidney disease with heart failure and with stage 1 through 4 chronic kidney disease, or unspecified chronic kidney disease, I50.21 Systolic, congestive, heart failure, acute, and N18.3 Chronic kidney disease, stage 3, moderate.
For hypertension with other conditions not listed above, provider documentation must link the conditions to code them as related.