Top DRG Codes by Diagnosis Volume

Diagnostic Related Groups, or DRGs, are primarily used to determine reimbursement for inpatient stays. Every inpatient visit is placed into one DRG category based upon the patient’s primary diagnosis, procedures performed, and discharge status. Each DRG is given a weighted value above or below one that represents the relative time and resources required to effectively care for the average patient with a specific diagnosis until discharge. This value is multiplied by a preset dollar amount unique to each hospital that reflects its individual status (teaching hospitals have higher reimbursements, for example) and service area demographics (such as average local wage levels) to find the total reimbursement amount. The average of a hospital’s DRG weights over a given period determines its case mix.

The most common primary diagnosis for hospital admissions by far is septicemia, followed by psychoses. In 2016, primary diagnoses for septicemia reached an estimated 1.3 million, and secondary diagnoses were approximately 24.5 million. Primary diagnoses for psychoses reached 1.9 million in 2016, and secondary diagnoses totaled more than 10.4 million. Part of the reason for the high psychoses volumes is the definition of the DRG itself, as its subcategories include multiple types of severe mental ailments that can require inpatient treatment, such as schizophrenia, bipolar disorder with manic episodes, and severe depression. Major joint replacement of the lower extremity (knee) without complications or co-morbidity was the third most common primary diagnosis, followed by heart failure & shock and pulmonary edema & respiratory failure.

Each of the top 10, with the exception of psychoses, also have related DRGs that specify additional characteristics for the patient group, such as the presence of major complications or comorbidities. For most of them, diagnoses involving complications or comorbidities were more common than those without. One important exception is knee replacement surgery, which is usually performed on an elective basis. Another is esophagitis and other gastrointestinal disorders.

Top 25 Diagnostic Related Groups by Volume

Fig 1. Data from Definitive Healthcare based on Annual Medicare Data from the 2016 Medicare SAF (1/1/2016 - 12/31/2016). Complete Calendar Year 2017 data is projected to be released in fall 2018 by the Centers for Medicare and Medicaid Services (CMS). All-Payer estimates are based on Definitive Healthcare calculations and algorithms.

Common Conditions by Associated DRG Diagnoses

Fig 2. Data from Definitive Healthcare based on Annual Medicare Data from the 2016 Medicare SAF (1/1/2016 - 12/31/2016). Complete Calendar Year 2017 data is projected to be released in fall 2018 by the Centers for Medicare and Medicaid Services (CMS). All-Payor estimates are based on Definitive Healthcare calculations and algorithms.