What Is HCC Medical Abbreviation (Hierarchical Condition Category)?
The HCC medical abbreviation is widely searched, but its meaning shifts depending on context. In coding, it refers to Hierarchical Condition Category (HCC coding), a core part of Medicare Advantage risk scoring.
Clinically, it refers to Hepatocellular Carcinoma, a common form of liver cancer. This article explains how providers, coders, and billers use the term, and where misunderstandings can lead to claim delays or underpayments.
Table of Contents
Understanding HCC Medical Abbreviation in Healthcare
The HCC Medical Abbreviation stands for Hierarchical Condition Category, a risk adjustment system developed by CMS to classify patient diagnoses based on severity and expected healthcare costs. It maps ICD-10 diagnosis codes into risk categories that help calculate a patient’s Risk Adjustment Factor (RAF) score.
The CMS HCC model groups over 9,700 ICD-10 codes into approximately 115 HCC categories, including chronic conditions like diabetes with complications (HCC 18) and heart failure (HCC 85). The HCC coding system ensures accurate healthcare payment adjustment by aligning reimbursement with patient health risk and medical complexity.
Step-by-Step Process of Hierarchical Condition Categories
The HCC risk adjustment workflow follows a defined clinical and coding process that converts diagnoses into risk scores and reimbursement values.
Step 1: Clinical Documentation and Diagnosis Capture
Providers document patient conditions during encounters using ICD-10 codes. Accurate HCC documentation must include evaluation, treatment, and management details to support compliance and reimbursement accuracy.
Example:
E11.22 – Type 2 diabetes with chronic kidney disease
I50.9 – Heart failure, unspecified
These codes are part of the standardized diagnosis coding system used globally in risk adjustment models.
Step 2: Mapping ICD-10 Codes to HCC Categories
Each diagnosis is mapped to specific HCC diagnosis codes under CMS guidelines to ensure accurate patient risk representation. This mapping determines whether a condition qualifies for risk adjustment & contributes to the patient’s RAF score and reimbursement.
Example mappings:
CMS maintains these mappings annually to ensure accurate cost prediction and reimbursement.
Step 3: Hierarchy and Severity Assignment
The system uses hierarchy logic. If multiple related diagnoses exist, only the most severe is counted within the defined HCC categories healthcare framework.
Example:
E11.9 → HCC 19 (Diabetes without complication)
E11.22 → HCC 18 (Diabetes with complication)
Only HCC 18 is counted because it represents higher severity and increased risk.
Step 4: Risk Score Calculation and Payment Adjustment
CMS calculates a RAF score based on:
Diagnosis categories
Age group (example: 70–74 years)
Gender
Medicaid eligibility
This supports accurate Medicare risk adjustment and ensures fair reimbursement.
The HCC Medical Abbreviation framework plays a critical role in converting clinical data into financial risk scores and reimbursement values.
HCC Codes List With Examples
HCC codes classify chronic and high-risk conditions based on ICD-10 diagnosis codes. They are used in Medicare risk adjustment to reflect patient severity, calculate RAF scores, and ensure appropriate reimbursement.
Common HCC Codes List in Medical Coding
Below are commonly used HCC codes in clinical practice and hcc medical coding workflows:
HCC 18 – Diabetes with complications (ICD-10: E11.22)
Includes diabetes with CKD, neuropathy, or retinopathy.
Example: Type 2 diabetes with CKD Stage 3 documented as diabetic nephropathy and managed with medication and nephrology follow-up.HCC 85 – Congestive Heart Failure (ICD-10: I50.9, I50.22)
Chronic heart failure requiring continuous treatment and monitoring.
Example: Patient with systolic heart failure (EF 35%) taking Lasix and under cardiology care.HCC 111 – Chronic Obstructive Pulmonary Disease (ICD-10: J44.9)
Chronic lung disease requiring long-term respiratory management.
Example: COPD patient using inhalers like Albuterol and Spiriva with pulmonary follow-up.HCC 136 – Chronic Kidney Disease Stage 4 (ICD-10: N18.4)
Severe kidney damage requiring specialist monitoring.
Example: CKD Stage 4 patient with GFR 24 mL/min under nephrologist care.HCC 12 – Breast Cancer (ICD-10: C50.919)
Includes active breast cancer under treatment.
Example: Patient receiving chemotherapy for invasive breast cancer.HCC 59 – Major Depressive Disorder (ICD-10: F33.1, F33.2)
Moderate or severe depression requiring active treatment.
Example: Patient treated with antidepressants and psychiatric follow-up.HCC 108 – Vascular Disease (ICD-10: I73.9)
Includes peripheral vascular disease affecting circulation.
Example: Peripheral artery disease treated with antiplatelet therapy.HCC 134 – Chronic Kidney Disease Stage 5 (ICD-10: N18.5)
Severe kidney failure requiring dialysis preparation.
Example: CKD Stage 5 patient scheduled for dialysis.
These codes represent high-risk conditions that require continuous monitoring and complete documentation to ensure proper risk adjustment and reimbursement. For more details on how Hierarchical Condition Categories work in risk adjustment, refer to this HCC coding and risk adjustment guide.
Top HCC Codes Used in Medical Coding
These HCC codes have a major impact on risk scores and reimbursement in risk adjustment programs. The most important and frequently reported HCC codes include:
HCC 85 – Heart Failure (ICD-10: I50.9, I50.22)
HCC 18 – Diabetes with Chronic Complications (ICD-10: E11.22, E11.40)
HCC 111 – Chronic Obstructive Pulmonary Disease (ICD-10: J44.9)
HCC 138 – Chronic Kidney Disease Stage 3 (ICD-10: N18.3)
HCC 136 – Chronic Kidney Disease Stage 4 (ICD-10: N18.4)
HCC 134 – Chronic Kidney Disease Stage 5 (ICD-10: N18.5)
HCC 59 – Major Depressive Disorder (ICD-10: F33.1, F33.2)
HCC 108 – Vascular Disease (ICD-10: I73.9)
HCC 12 – Breast Cancer (ICD-10: C50.919)
HCC 19 – Diabetes without Complications (ICD-10: E11.9)
These diagnoses require annual chronic condition reporting to remain valid in risk calculations. Healthcare providers must document these conditions at least once every 365 days for inclusion in RAF scoring.
HCC Diagnosis Category List in Healthcare Billing
HCC diagnosis categories group chronic and high-risk conditions based on severity and cost to support proper risk scoring and reimbursement. Below are the major HCC diagnosis categories commonly used in healthcare billing and risk adjustment:
Cardiovascular Conditions
These categories include serious heart conditions requiring continuous monitoring and treatment.
HCC 85 – Congestive Heart Failure: Includes systolic and diastolic heart failure with high hospitalization risk.
HCC 96 – Cardiac Arrhythmias: Includes abnormal heart rhythms such as atrial fibrillation (ICD-10: I48.91).
These conditions often require medication, cardiac monitoring, and specialist care.
Metabolic Conditions
These include endocrine disorders affecting multiple body systems.
HCC 18 – Diabetes with Complications: Includes diabetes with CKD, neuropathy, retinopathy, or vascular complications.
Diabetes with complications significantly increases patient risk scores.
Respiratory Conditions
These categories include chronic lung diseases affecting breathing.
HCC 111 – Chronic Obstructive Pulmonary Disease (COPD): Includes emphysema and chronic bronchitis.
Patients often require inhalers, oxygen therapy, and pulmonary follow-up.
Renal Conditions
These include chronic kidney disease and advanced renal failure stages.
HCC 134 – CKD Stage 5
HCC 135 – End-Stage Renal Disease
HCC 136 – CKD Stage 4
HCC 138 – CKD Stage 3
Severity is determined based on kidney function (GFR levels).
Cancer Conditions
These include active cancers requiring treatment or management.
HCC 8 – Metastatic Cancer
HCC 9 – Lung and Severe Cancers
HCC 11 – Colorectal, Bladder, and Other Cancers
HCC 12 – Breast and Prostate Cancer and Other Organ Cancers
Only active cancer diagnoses qualify for HCC reporting and risk adjustment. Want to know how HCC Coding maximizes reimbursement? Find out here:
Risk Adjustment Factor (RAF) Score in HCC Coding Model
The HCC RAF score is calculated based on patient demographics and documented HCC conditions. Each HCC category has a CMS-assigned risk weight, and the combined score is used in Medicare risk adjustment to estimate healthcare costs and determine reimbursement.
Typical RAF score components:
Higher RAF scores indicate higher expected medical expenses and reimbursement levels. The HCC Medical Abbreviation system ensures risk scores accurately reflect patient severity and cost burden.
Importance of HCC Codes in Healthcare and Medicare
The importance of HCC coding lies in its ability to link patient diagnoses with reimbursement accuracy and healthcare planning.
Key benefits include:
Accurate risk stratification
Improved financial planning
Better population health management
Enhanced clinical documentation improvement and compliance
Correct coding also supports quality measurement and regulatory compliance.
Common Mistakes in HCC Medical Coding
Several HCC Coding Mistakes can lower RAF scores and reduce reimbursement. Avoiding these errors ensures proper risk adjustment and compliance.
Missing Annual Documentation
HCC conditions must be documented at least once every 365 days. If a chronic condition like diabetes or CHF is not reported in the current year, it will not count toward risk scoring. Proper HCC documentation supports valid chronic condition reporting and reimbursement.
Using Unspecified Diagnosis Codes
Unspecified codes may not map to HCC categories and can result in missed risk capture.
Example:- Incorrect: E11.9 – Diabetes without complications
- Correct: E11.22 – Diabetes with CKD (maps to HCC 18)
Using specific HCC diagnosis codes ensures correct risk adjustment.
Incomplete Clinical Documentation
Providers must document active management such as evaluation, monitoring, or treatment. Missing details in healthcare coding and billing can lead to incorrect code mapping and lower RAF scores. Proper documentation ensures accurate HCC reporting and compliance.
Get Expert HCC Coding Support
Proper HCC coding ensures correct RAF score calculation, compliance, and appropriate reimbursement in risk adjustment programs. Incomplete documentation or incorrect diagnosis coding can lead to missed revenue and reporting gaps.
Our expert HCC Coding Services help improve coding efficiency, close documentation gaps, and optimize risk adjustment outcomes.
Contact MBW RCM today to learn how our experts can support your HCC coding and reimbursement needs.
FAQs: HCC Coding & Risk Adjustment in Healthcare
Request for Information
Facing challenges with HCC coding, incomplete documentation, or risk adjustment gaps? An HCC coding expert can help improve coding compliance, RAF score capture, and reimbursement accuracy.
Fill out the form below to connect with a specialist and optimize your HCC coding and risk adjustment performance.
