Book excerpt: HCC basics
Complete Training Guide
By Tracy Boldt, RN, BSN, CCDS, CDIP, and Ellen Jantzer, RN, MSN, CCDS, CCS, CRC
The hierarchical condition categories (HCC) are diagnosis code based on ICD-10 codes and include approximately 70 distinct disease groups derived from approximately 3,600 diagnosis codes that are mostly chronic but include some acute conditions, used primarily for outpatient services. The ICD-10 code book published by Optum includes the HCC designation along with CC/MCC. APCC and HCC University both have interactive tools to identify HCC codes.
The relationship between the ICD-10-CM diagnoses codes and the HCCs is one to many, meaning a single HCC may contain any number of ICD-10 diagnoses codes. Each HCC is assigned a relative factor or health risk score that is used to compute the patient’s risk adjustment factor. For example, HCC 21, Protein Calorie Malnutrition, includes:
- E41 Nutritional Marasmus
- E42 Marasmic Kwashiorkor
- E43 Unspecified Severe Protein Calorie Malnutrition
- E44.0 Moderate Protein Calorie Malnutrition
- E44.1 Mild Protein Calorie Malnutrition
- E45 Retarded Development following PCM
- E46 Unspecified Protein Calorie Malnutrition
- E64.0 Sequelae of Protein Calorie Malnutrition
- R64 Cachexia or Wasting Syndrome
Not all ICD-10-CM codes are reflected in HCC groupings; CMS identified diagnoses which:
- Are related to high costs
- Complicate coordination of care
- Increase potential care needs or medications
The list of such diagnoses and their corresponding HCC is updated annually by CMS and can be found here.
The basic HCCs categories include:
- Infection
- Neoplasm
- Diabetes
- Cerebrovascular disease
- Vascular
- Lung
- Metabolic
- Liver
- Gastrointestinal
- Musculoskeletal
- Eye
- Kidney
- Openings
- Amputations
- Blood
- Substance abuse
- Skin
- Injury
- Psychiatric
- Spinal
- Neurological
- Arrest
- Heart
- Complications
- Transplants
The ultimate payment is per HCC (not per diagnosis code), similar to the DRG system on the inpatient side, and is based on the highest-rated HCC within a category.
Editor’s note: This is an excerpt from The Outpatient CDI Specialist’s Complete Training Guide.