In numerous tables in Marketscape, you will find tables that contain Diagnostic Groupings that organize metrics in the table. These groups, in general, contain similar diagnoses that align with an organ system or related medical specialty. Our groupings are based on the ICD-10-CM Chapters which divide all ICD-10 codes into 21 groups with specific code ranges. The table below shows this alignment with some important qualifications.
For more information on the ICD-10 Chapters, click ICD-10-CM Chapters.
We have also provided a spreadsheet that will allow you to look up a specific ICD-10 code and pinpoint which chapter is matched to each ICD-10 code, and consequently to the Trella Health Diagnostic group in the table.
Although many places in Marketscape mention "Diagnostic Categories," or "Major Diagnostic Categories," do not try to draw a connection to CMS's Major Diagnostic Categories (MDC). In some cases you will be able to find an obvious similarity, but the alignment will not work for all groupings or diagnoses.
This sample image shows how the Trella Health Diagnostic Groupings appear in a table. It is possible that some diagnostic groups will not be represented in a table. If there are no claims to populate a diagnostic group, we will not include that group in the table. Also, if the patient count in a group is too small to reveal, that is, the patient count is less than 11 (<11) we will add that group to the category, Aggregated INS MDCs.
Understanding each Chapter
The purpose of this document is to alert Marketscape users to the most common primary diagnosis codes used in various aspects of post-acute care grouped by ICD-10 Chapters.
Readers should be aware that codes from Chapter 21 – Factors Influencing Health Status – are not generally grouped since these codes, which, used as primary diagnoses, are related to a variety of conditions brought on by other conditions. Such codes include aftercare for various types of surgical procedures which are among the most commonly used codes related to home health or SNF stays following a hospital discharge. Similarly, for hospice, the primary code is expected to relate to the illness mostly likely to directly relate to the patient’s near-term terminal prognosis. As such, each primary diagnosis for hospice would be considered, in its end stages, to be a terminal disease. In each of the chapters referenced below, we have identified the conditions that would most often appear as a primary post-acute diagnosis.
Chapter 1 - Infectious Diseases - A00-B99
Chapter 1 of the ICD-10 schema includes codes beginning with A and B, denoting certain types of infectious diseases, the most common of which in a home health setting is Sepsis. Sepsis diagnoses are further broken down into several causal categories such as E. coli, MRSA, and enterococcus. Other often occurring home health diagnoses include Candidiasis which is a fungal infection and Enterocolitis associated with clostridium difficile, otherwise known as CDiff. The majority of the diagnoses that fall into Chapter 1 are reported under the home health MMTA Infectious Disease Clinical Group and comprise only about 5% of all home health primary conditions.
For hospice, although not common, the most oft cited infectious disease that forms the terminal condition relates to severe sepsis. Infectious diseases that often necessitate skilled nursing care following a hospital discharge include COVID-19 certain forms of pneumonia and sepsis all of which can have accompanying debilitation that requires intensive nursing and therapy following the patient’s hospital discharge.
Chapter 2 - Neoplasms - C00-D49
Chapter 2 includes all forms of cancers or neoplasms and the majority of most frequently used diagnoses fall into the home health MMTA Infectious Disease Clinical Group. The exceptions are malignant neoplasm and secondary malignant neoplasm of the brain which are considered Neuro-Rehab conditions. Cancers that are most often treated by home health include cancer of the colon, bladder, lung, breast, rectum and bone. Leukemia is also included in this category. Diagnoses from this chapter are also often associated with the terminal illness affecting hospice patients.
Neoplasms are often identified as the terminal disease for hospice patients. In fact, in the early days of hospice care, most hospice patients had some form of terminal cancer. Cancers that are most prevalent as hospice terminal diagnoses include lung cancer, colon cancer and pancreatic cancer.
Patients with diagnosed cancers are rarely referred for care in a skilled nursing facility unless they have undergone an inpatient surgical procedure that necessitates a short period of post-operative recovery requiring more intensive, facility-based nursing and/or therapy services.
Chapter 3 - Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism - D50-D89
Diagnoses most often used in home health from Chapter 3 also fall into the MMTA Infectious Disease Clinical Group. Disorders most often treated by home health agencies as primary conditions include Vitamin B12 Deficiency, anemia, iron deficiency anemia, thrombocytopenia and sarcoidosis of the lung.
This group of diagnoses is relatively small. Blood and immune disorders do not often precipitate care in a skilled nursing facility and are also relatively uncommon as the terminal diagnosis for hospice that would justify hospice care.
Chapter 4 - Endocrine, Nutritional and Metabolic Diseases - E00-E89
The condition that is most often associated with home health from this chapter of codes is diabetes which falls into the MMTA Endocrine Clinical Group. However, when diabetes is accompanied by a complication such as a wound, the wound is considered the focus of care in home health and is grouped in the Wound Clinical Group with significantly higher overall reimbursement. Dehydration, hypo-osmolality with hyponatremia and hypothyroidism are also among the diagnoses most often seen for home health. Endocrine disorders make up about 5% of all home health primary diagnoses and would not generally be associated with protracted length of stay unless the condition is uncontrolled or severe complications are present.
While endocrine and nutritional disorders are common in home health, they are generally not as common as the primary diagnosis that leads to a finding of terminal status for hospice or a need for facility based skilled nursing care. Often diabetes is the underlying condition that begets other related conditions such as congestive heart failure or kidney disease; however, and as such diabetes is a causative factor for other illnesses that may have more severe outcomes and may necessitate the need for facility based care and or end of life care.
Chapter 5 - Mental, Behavioral and Neurodevelopmental Disorders - F01-F99
The diagnoses that are typically seen from this chapter include major depressive disorder, bipolar disorder, schizoaffective disorders, anxiety and unspecified dementia with or without behavioral disturbances. These diagnoses almost exclusively fall into the Behavioral Clinical Group and constitute the lowest percentage of all home health cases at 2%. Most agencies treat small numbers of patients for whom the focus of care is a primary mental or behavioral disorder, if any.
These disorders are uncommon as hospice primary diagnoses and also do no, as a general rule, lead to a need for nursing and therapy services in a SNF setting.
Chapter 6 - Diseases of the Nervous System - G00-G99
Often diseases that fall into this diagnostic chapter are thought by some to be mental conditions, but they are not. Most prevalent home health diagnoses include Parkinson’s, Alzheimer’s, amyotrophic lateral sclerosis (ALS), dementia with Lewy bodies, cerebral palsy, encephalopathy, transient cerebral ischemic attack (TIA and often called a mini-stroke) and hereditary neuropathy. All of these conditions fall into the highly reimbursed Neuro-Rehab Clinical Group which comprises about 9% of all home health services. Other diagnoses from this chapter that are often seen in conjunction with home health services include epilepsy and chronic pain which fall into the lesser MMTA Other category of reimbursement.
Alzheimer’s disease and other forms of dementia are now among the leading diagnoses that form the basis of a terminal finding in hospice. Alzheimer’s in its late stages will often result in aspiration pneumonia, kidney infections, pressure ulcers, loss of speech and protein calorie malnutrition. Similarly, it is not unusual to see Parkinson’s disease, senile degeneration of the brain or ALS as a hospice terminal diagnosis.
Diseases of the nervous system including MS, Parkinson’s disease, Muscular Dystrophy and Myasthenia Gravis are also often accompanied by significant deconditioning, nutritional impairment and disease progress that lead to hospice or form the basis for skilled nursing and facility based therapy services.
Chapter 7 - Diseases of the Eye and Adnexa - H00-H59
There are very, very few diagnoses from this chapter that would be considered a focus of home health care. In fact, the only one that shows up in cases is glaucoma and that is rare unless the condition is newly diagnosed and the patient has mobility and fall risk issues associated with the vision loss. All of these diagnoses, to the extent permitted as a primary home health diagnosis, would fall into the MMTA Other Clinical Group.
These diseases are generally not cited as hospice terminal diagnoses and are also unlikely to be the causative factor necessitating care in a SNF.
Chapter 8 - Diseases of the Ear and Mastoid Process - H60-H95
As with the conditions in Chapter 7, disease processes from this chapter are also rare in home health. The only that will show up, although rarely, is vertigo that could be associated with loss of balance, falls and the presence of continuing high fall risk.
These diseases are generally not cited as hospice terminal diagnoses and are also unlikely to necessitate care in a SNF setting.
Chapter 9 - Diseases of the Circulatory System - I00-I99
These conditions are often the focus of home health services generally falling into the MMTA Cardiac category. Cardiac diagnoses include hypertensive heart disease with or without heart failure, hypertensive heart and chronic kidney disease, atherosclerotic heart disease of the native coronary artery (a/k/a coronary artery disease or CAD), venous insufficiency, atrial fibrillation, Non-ST elevation (NSTEMI) myocardial infarction, peripheral vascular disease, pulmonary embolism, and congestive heart failure (CHF).
Other diagnoses from this chapter, however, fall into other Clinical Groups including conditions such as hemiplegia associated with cerebral infarction which are in Neuro Rehab or hyper/hypotension which show up ion MMTA Other. At one time, hypertension as a primary focus of care was so ubiquitous that CMS threatened to ban it as a primary diagnosis for home health services. It didn’t happen, but readers should be aware of the distinction.
MMTA Cardiac cases generally comprise about a fifth of all home health cases.
Congestive heart failure, hypertensive heart disease and other cardiac illnesses, in their end stages, are often cited as hospice terminal diagnoses. Similarly, because these illnesses are often accompanied by significant debilitation and dyspnea, they can be the primary diagnosis that gives rise to facility based SNF care following a hospital discharge related to a disease exacerbation.
Chapter 10 - Diseases of the Respiratory System - J00-J99
Respiratory illnesses are included in this chapter. The most frequently diagnosed home health condition is COPD followed by various forms of pneumonia, emphysema, acute bronchitis, pleural effusion, respiratory failure, asthma and flu. The new COVID-19 diagnosis, U07 is also included in this category but readers should be aware that other diagnoses associated with COVID-19 such a multi-system organ failure, etc. are not coded here. All of the prevalent diagnoses in this chapter fall into the MMTA Respiratory Clinical Group.
End stage COPD is the most prevalent hospice diagnoses in this grouping. Because diseases in this category are often accompanied by significant deconditioning, they can also be the reasons patients require post-hospital facility based SNF services for functional improvement.
Chapter 11 - Diseases of the Digestive System - K00-K95
Diseases in this chapter generally fall into the MMTA GI/GU Clinical group which amounts to only about 5% of all cases. Conditions that we often see here include gastrointestinal hemorrhage, gastroenteritis and colitis (non-infectious), gastro-esophageal reflux disease (GERD), cirrhosis of the liver, hepatic failure, diverticulitis, pancreatitis, malabsorption issues and rectal abscesses.
These are not typically found as hospice primary diagnoses; however, some of the illnesses in this category, if severe enough to warrant hospitalization, can lead to SNF care before the patient is able to return home following a hospital discharge.
Chapter 12 - Diseases of the Skin and Subcutaneous Tissue - L00-L99
Wounds comprise more than 10% of all home health cases. The most prevalent form of coded wound is a pressure ulcer usually in the sacral region, buttocks and feet. Cellulitis of the lower extremities would also be coded in this chapter and would be considered a wound for home health purposes.
Wounds are not generally considered terminal in and of themselves and do not, as a result, show up as the primary diagnosis for hospice care even though wounds among hospice patients are common. Likewise, a wound, unless very severe would not be a likely candidate as the primary diagnosis for post-hospital, facility based services.
Chapter 13 - Diseases of the Musculoskeletal System - M00-M99
All of these conditions fall into the MS Rehab Clinical Group which comprises about a fifth of all home health cases. Be aware, however, that this is not where we would find lower extremity joint replacements as the aftercare associated with such procedures is associated with a Z code from Chapter 21. Trella does not, I believe, include these diagnoses in its listing of conditions. Business development teams should know that. What does fall into this category is also differentiated from musculoskeletal injuries, such as fractures, which are coded in Chapter 19.
With the foregoing in mind, diseases of the musculoskeletal system include osteoarthritis (OA – most often of the knees and hips), spinal stenosis, lumbar radiculopathy, disc degeneration, age-related osteoporosis, cervicalgia, spondylosis, lumbago with sciatica, and fibromyalgia.
These diseases do not often form the basis for hospice care, but often do form the need for SNF care following an inpatient procedure even though the procedure itself may lead to a diagnosis related to aftercare found in Chapter 21.
Chapter 14 - Diseases of the Genitourinary System - N00-N99
As with digestive diseases, all of the diseases in this chapter that are frequently found as home health primary diagnoses are assigned to the MMTA GI/GU group. The condition most often established as a home health diagnosis is UTI followed by prostatic hyperplasia, neuromuscular dysfunction of the bladder, acute cystitis, kidney failure and chronic kidney disease (all stages through 4 as Stage 5 ESRD cannot be used as a home health primary diagnosis).
Acute kidney failure, end stage renal failure (ESRD) and other kidney disorders can progress to the point of being designated as a terminal disease for hospice. Likewise, depending on the severity of the disease and the degree of patient deconditioning as a result of the disease process and hospitalization, genitourinary diseases can be the basis for SNF care aimed at functional improvement and post-discharge stabilization that would enable the patient to safely return home.
Chapter 15 - Pregnancy, Childbirth and the Puerperium - O00-O9A
There are no diagnoses associated with this chapter that regularly form the basis for Medicare reimbursed home health.
These diseases are generally not cited as hospice terminal diagnoses and are also rare as causes for SNF based care.
Chapter 16 - Certain Conditions Originating in the Perinatal Period - P00-P96
As with Chapter 15, there are no diagnoses associated with this chapter that form the basis for Medicare reimbursed home health.
These diseases are generally not cited as hospice terminal diagnoses and never applicable to SNF based care.
Chapter 17 - Congenital Malformations and Deformations - Q00-Q99
There are very few conditions from this chapter that show up for elderly home health patients. Those that do include Down syndrome, spina bifida and hereditary lymphedema.
These diseases are generally not cited as hospice terminal diagnoses.
Chapter 18 - Symptoms, Signs and Abnormal Clinical and Laboratory Findings - R00-R99
These diagnoses, which begin with the letter R, are not allowed primary diagnoses under PDGM. The signs and symptoms in this chapter, however, are often used as secondary diagnoses and include things such as weakness, abnormality of gait, etc.
These diseases are generally not cited as hospice terminal diagnoses and would never be the subject of a SNF admission.
Chapter 19 - Injury and Poisoning and Certain Other Consequences of External Conditions - S00-T88
This chapter includes all of those home health diagnoses that are usually caused by some type of injury – most often for elderly patients, a fall. This includes fractures, most often of the femur and humerus and rib fractures. With the exception of rib fractures, these are conditions that are most often surgically treated and fall into the MS Rehab grouping. Also in this chapter are traumatic wounds, usually of the lower extremities and all are included in the home health Wound grouping. Finally, a frequent home health diagnosis from this chapter is traumatic subdural hemorrhage with or without loss of consciousness and that condition is considered among the Neuro-Rehab diagnoses.
Fractures are often the basis for SNF-based care for patients who are more elderly, frail and in need of extended therapy to restore function following an injury. These conditions are rarely terminal and, thus, not found as terminal diagnosis for justification of hospice care.
Chapter 20 - External Causes of Morbidity - V00-Y99
Not used for home health or hospice as these are causes of death. The same is true for SNF services.
Chapter 21 - Factors influencing health status and contact with health services - Z00-Z99
This is one of the most important chapters for home health as it includes all of those inpatient or outpatient procedures for which home health teams are providing aftercare. The number one home health diagnosis in this chapter that relates to home health services is Z47.1 which is used for all types of home health services related to joint replacements.
Other common procedures that provided the basis for post-hospital discharge home health include the following from this chapter:
- Complex Nursing: Fitting and adjustment of urinary device (Foley catheter), and attention to cystostomy, vascular access devices, gastrostomy, other artificial openings of the urinary tract, and colostomies. These are all generally low volume services.
- MMTA Surgical Aftercare: Surgery on the circulatory system, surgery for neoplasm, surgery on the skin, and genitourinary related procedures.
- Wound care includes services related to removal of surgical wound dressings.
These diagnoses are generally not used as primary diagnoses for hospice but can be the basis for SNF care when patients who are medically fragile with other serious comorbid conditions.
Aggregated INS DG's
The entry titled, “Aggregated INS MDC’s” represents the combined percentage for all diagnostic groupings that are too small to be presented on their own. In any case where the total number of patients in a specific diagnostic group drops below 11 patients, we can't show that number for privacy reasons. We roll all diagnostic groups that represent counts <11 into this one category and present that total percentage under this header. Another way to look at it: this row includes all diagnostic groups that have insufficient counts aggregated into a single metric. It is possible that this group itself could contain less than 11 (<11).
Locating a Specific Diagnosis
The attached spreadsheet contains the ICD-10 diagnoses codes, their descriptions along with the ICD-10-CM chapters to which each diagnosis aligns. In addition, we have listed the diagnostic groupings names as they are found in Marketscape. By searching for a specific ICD-10 code, you can identify how that diagnosis aligns with the metrics in Marketscape. Instructions are included in the Spreadsheet.