Author: Kristina Finley, CPC
Consultant, HCC Coding/Audit and Education



(303) 801-0111


March is Kidney Awareness Month, and Pinnacle wants to share updates regarding the new conversion from v24 to v28.  What better way to celebrate than to brush up on how kidney and underlying kidney related diseases affect Risk Adjustment!? As we move forward over the next three-year implementation, it is important to understand how this new model will affect everything we know about Medicare Advantage and Risk Adjustment.

Chronic kidney disease (“CKD”), also known as chronic kidney failure, is a condition in which kidney function gradually declines. In its early stages, symptoms may not be recognized, due to the low impact of the disease. However, as the disease progresses it can lead to End Stage Renal Disease (“ESRD”), which is fatal without hemodialysis, peritoneal dialysis, or a kidney transplant.

Below are the five (5) Hierarchical Condition Categories (“HCCs”) diagnosis codes from v24 that directly correspond to a patient’s renal status:

  • HCC 134 – Dependence on Renal Dialysis
  • HCC 135 – Acute Renal Failure
  • HCC 136 – Chronic Kidney Disease, (Stage 5 or ESRD)
  • HCC 137 – Chronic Kidney Disease, Severe (Stage 4)
  • HCC 138 – Chronic Kidney Disease, Moderate (Stage 3)

Did you know there are also several additional underlying conditions that involve the renal system which can also lead to an HCC risk adjustment factor (RAF)?

  • HCC 23 – Secondary hyperparathyroidism of renal origin
  • HCC 18 – Diabetes Mellitus with kidney complications
  • HCC 107 – Ischemia and infarction of kidney


Documentation & Coding

Now that we’ve reviewed several kidney conditions and their HCC categories, let’s discuss how code assignment and documentation errors can affect risk adjustment payments. CKD is one of the most improperly documented and assigned diagnosis codes. Unfortunately, common errors typically revolve around diagnosis acuity and specificity! The ICD-10-CM Official Guidelines for Coding and Reporting can be “due to” hypertension and diabetes; even when the provider does not link them.  This guideline is appropriate, unless the provider specifically links the CKD to another condition.  The guidelines also indicate to report an additional code for the stage of CKD, which is a requirement.  One must also remember CKD cannot be reported from diagnostic reports (e.g., laboratory results).  The provider must enter a status and / or plan into the progress note, assess the current stage of CKD, and document any pertinent findings in the progress note as well. The provider should always document to the highest specificity of the disease.

The medical record should include whether the CKD is an acute and / or chronic condition.  The CKD stage should be reported by the provider along with a review of most recent eGFR values to avoid the provider listing multiple stages of the CKD within the progress note.  The provider must “link” any underlying etiologies or manifestations to the CKD and specify any validation complications arising from the condition. Lastly, as we all know, after the implementation of v28 many unspecified diagnosis codes are no longer payable under HCC reimbursement. Therefore, we should remember to avoid diagnosis codes such as N18.9 (chronic kidney disease, unspecified) and N28.9 (disorder of kidney and ureter, unspecified).


The ‘With, And, and Due To’ Conundrum

ICD-10-CM Official Guidelines for Coding and Reporting provides us with the gift of Section A.15 – “With.”  This guideline states the coder should interpret the word “with” or “in” to mean “associated with” or “due to” when it appears in a code title, the Alphabetic Index, or instructional note in the Tabular List.  This guideline presumes a “causal relationship” between the two conditions linked by these terms. However, this guideline is confusing and often misinterpreted by HCC risk adjustment coders.  As the guideline mandates, “These conditions should be coded as related even in the absence of provider documentation explicitly linking them…”. Does this mean an HCC coder could allow diabetic chronic kidney disease “with” chronic kidney disease stage IV to be reported without supporting documentation?  The answer is NO.  Although we are gifted the ability to “presume” the linking relationship, to capture the HCC risk adjustment factor the guidelines for HCC coding and reporting must also be met.

There is a perfect example provided by AHA® Coding Clinic Hypertension, Diabetes Mellitus and CKD (2018 Vol. 5, No. 4.)

Question: Since ICD-10-CM presumes a relationship between both chronic kidney disease (CKD) and hypertension as well as diabetes mellitus and CKD, what are the appropriate code assignments when the provider documents type 2 diabetic mellitus with chronic kidney disease and the patient also has a diagnosis of hypertension?

Answer: Assign codes E11.22, Type 2 diabetes mellitus with diabetic chronic kidney disease, I12.9, Hypertensive chronic kidney disease with stage 1 through stage 4 chronic kidney disease, or unspecified chronic kidney disease, and N18.9, Chronic kidney disease, unspecified. The classification presumes a cause-and-effect relationship between both diabetes and CKD and hypertension and CKD. CKD is most likely related to both hypertension and diabetes when the patient has all three conditions. Both high blood sugar and high pressure in the blood vessels will cause the vessels to deteriorate, which can then damage the kidneys.

As of October 1, 2018, the ICD-10-CM Official Guidelines for Coding and Reporting have been revised to read, “Assign codes from category I12, Hypertensive chronic kidney disease, 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 provider indicates the CKD is not related to the hypertension.” (Emphasis made by article author)


The Conclusion

The Assessment and Plan (“A/P”) can be likened to the conclusion of an essay.  It brings the documentation to a close with final thoughts.

For standard coding guidelines, the diagnosis is all that is required to be listed in the A/P; however, the HCC coding guidelines require a Diagnosis, Status, and Plan (“DSP”). The A/P should include a minimum of the diagnosis and status OR the diagnosis and plan, but preferably all 3 should be documented to cover all bases and to provide the best documented care for the patient. The DSP includes:

  • Diagnosis: Signs, symptoms, disease (signs and symptoms are not to be documented if a definitive diagnosis is provided).
  • Status: Disease regression, progression, test results, medication, response to treatment.
  • Plan: Diagnostic testing orders, discussion of disease with the patient, reviewing outside records, providing counseling and referral to another provider, prescribe medications, therapy, and other modalities.

The A/P is going to make or break your risk adjustment payments if the diagnoses are not properly documented and assessed according to the above-mentioned model.

Now, assuming all conditions are documented properly, how do the v24 and v28 models compare to / affect your reimbursement?  Let’s take a look!

ICD-10Descriptionv24RAF Scorev28RAF Score
E10.22Type 1 Diabetes with CKDHCC180.252HCC370.154
E11.22Type 2 Diabetes with CKDHCC180.252HCC370.154
I12.9Hypertensive CKD stage 1-4N/A0N/A0
I12.0Hypertensive CKD stage 5-6HCC1360.241HCC3260.756
I13.0Hypertensive CKD 1-4 with Heart FailureHCC850.276HCC2260.334
I13.10Hypertensive CKD 1-4 without Heart FailureN/A0N/A0
I13.11Hypertensive CKD 5-6 without Heart FailureHCC1360.241HCC3260.756
I13.2Hypertensive CKD 5-6 with Heart FailureHCC85 & HCC1360.276 & 0.241HCC226 & HCC3260.334 & 0.756
 Also code the stage of CKD    
N18.1Chronic Kidney Disease, stage 1N/A0N/A0
N18.2Chronic Kidney Disease, stage 2N/A0N/A0
N18.31Chronic Kidney Disease, stage 3aHCC1380.058HCC3290.118
N18.32Chronic Kidney Disease, stage 3bHCC1380.058HCC3280.118
N18.4Chronic Kidney Disease, stage 4HCC1370.241HCC3270.477
N18.5Chronic Kidney Disease, stage 5HCC1360.241HCC3260.756
N18.6Chronic Kidney Disease, stage 6 (ESRD)HCC1360.241HCC3260.756
Z99.2Dependence on renal dialysisHCC1340.363N/A0
Z91.15Noncompliance with renal dialysisHCC1340.363N/A0

As you can see, there are several drastic changes that occur between RAF scores related to CKD.  In the v28 model, the RAF scores go up (all except DM with CKD).  You can also see RAF scores for dialysis status codes disappear in the v28 model and the RAF scores rise dramatically for higher stages of CKD. This makes it all the more imperative CKD staging is documented and addressed properly using the DSP method described in this article.



What happens when codes which risk adjust are submitted without proper support?  The Office of the Inspector General (“OIG”) released their compliance audit of diagnosis codes that Humana, Inc (“Humana”) submitted to the Centers for Medicare & Medicaid Services (“CMS”) for payment year 2015 for their Florida Seniors program.  The OIG found 1,322 of the 1,525 sampled HCCs were validated but the remaining 203 HCCs were not. Of those 203 invalid HCCs, twenty (20) were replaced with twenty-two (22) different HCCs reflecting either more, or sometimes less severe, manifestations of the diseases which were originally submitted.  An additional 15 HCCs were supported by the medical records but were not submitted to CMS by Humana.  The result of this audit was Humana was overpaid $197.7 million dollars for just one state!

Accuracy by both providers and HCC risk adjustment coders is critical.  There is an important and subtle balance in our field which affects both the general public and enrollees in Medicare Advantage (“MA”) plans.  When risk adjusted codes are submitted, but not supported, CMS overpays the MA plans using federal money (tax dollars) which directly affects the general tax paying public (us).  Over ninety percent (90%) of patients will never be audited.  When diagnoses are not submitted properly using the correct diagnosis codes, or not submitted at all, this directly affects the funds needed so patients receive the care they deserve.  As risk adjustment coders, it is essential to code accurately, truthfully, and always with integrity.


For more information, please contact Consultant, HCC Coding/Audit and Education Kristina Finley at or 904-859-3170.