Navigating the Complexities of Diabetes Medication Coding

Table of Contents

Understanding the Complexities of Billing for Diabetes Medications

Complexity of Diabetes Coding:

- Diabetes coding is complex due to several factors:
  - Type of diabetes (Type 1, Type 2, etc.)
  - Etiology of secondary diabetes
  - Diabetic complications
  - Diabetes control status (stable, uncontrolled, progressing, etc.)
  - Medications or insulin treatments, including use of insulin pumps and continuous glucose monitors.

Key Considerations for Coders:

- Type of Diabetes: Coders must determine the type of diabetes, whether it is Type 1, Type 2, or a secondary form.
- Control Status: Coders need to assess whether the diabetes is under control or uncontrolled. If uncontrolled, clarification is needed to specify if it is hyperglycemia or hypoglycemia.
- Treatment: Coders must verify if insulin, other medications, or devices like insulin pumps are being used. They should also check if continuous glucose monitors are being reviewed.

Basic Understanding of Diabetes:

- Diabetes: A chronic condition that affects the body’s ability to process glucose properly.
- Insulin and Blood Glucose: The pancreas releases insulin in response to elevated blood glucose to help cells absorb glucose for energy.
- Complications: Chronic hyperglycemia can lead to complications like cardiovascular disease, neuropathy, nephropathy, eye disease, and diabetic ketoacidosis.

Types of Diabetes:

- Type 1 Diabetes: A condition where the pancreas produces no insulin. It is usually diagnosed in childhood. It is coded under E10.-. Insulin is required for survival.
  - E10.A-: New code for presymptomatic Type 1 diabetes.
- Type 2 Diabetes: The pancreas produces insulin, but the body is resistant to it. It is the most common type, coded under E11.-.
- Latent Autoimmune Diabetes in Adults (LADA): A mix of Type 1 and Type 2, coded under E13.-.
- Secondary Diabetes: Caused by other conditions or medications, such as E08.- (due to a condition) or E09.- (induced by drugs/chemicals).

Medications for Diabetes:

- Medications include insulin, oral hypoglycemics, and non-insulin injectable medications. Coders must use Z79 codes to indicate the long-term use of these medications:
  - Z79.4: Long-term insulin use
  - Z79.84: Long-term use of oral hypoglycemic drugs
  - Z79.85: Long-term use of injectable non-insulin antidiabetic drugs
- Exception for Type 1 Diabetes: Insulin use is assumed, and additional codes for non-insulin medications are only used when medically necessary.

Coding Insulin and Medications:

- Guideline I.C.4.a.3 explains how to code the use of medications to control diabetes:
  - Type 2 Diabetes: Use E11- code and appropriate Z79 code for insulin, oral hypoglycemics, or injectable non-insulin antidiabetic medications.
  - Example:
    - A stable Type 2 diabetes patient using metformin and Victoza: E11.9, Z79.84, Z79.85.
    - A patient with secondary diabetes due to cystic fibrosis: E08.9, Z79.4, Z79.84, Z79.85.

Example 1: Stable Type 2 Diabetes Management

A patient has Type 2 diabetes (ICD-10 code E11.9), which is stable and under control with no complications. The patient is prescribed Metformin (an oral hypoglycemic medication) and Victoza (a non-insulin injectable medication).

Metformin: This medication is a common oral hypoglycemic used to manage blood sugar levels in Type 2 diabetes. It should be coded under Z79.84, which indicates long-term use of oral hypoglycemic drugs.
Victoza: This is an injectable non-insulin medication used to control blood sugar levels. It should be coded under Z79.85, indicating long-term use of injectable non-insulin antidiabetic drugs.

Coding:

Primary Diagnosis: E11.9 (Type 2 diabetes without complications)
Medication Codes:
- Z79.84 (Long-term use of oral hypoglycemic drugs)
- Z79.85 (Long-term use of injectable non-insulin antidiabetic drugs)

This coding ensures that both the diabetes diagnosis and the specific medications being used are properly documented for accurate billing.

Example 2: Secondary Diabetes Due to Cystic Fibrosis

A patient has secondary diabetes resulting from cystic fibrosis (ICD-10 codes E84.9 for cystic fibrosis and E08.9 for secondary diabetes due to another condition). The diabetes is managed with a combination of three medications: Lantus, Jardiance, and Trulicity.

Lantus: This is a long-acting insulin, which should be coded under Z79.4 to indicate long-term insulin use.
Jardiance: An oral hypoglycemic medication used to control blood sugar in Type 2 diabetes. It should be coded under Z79.84 for long-term use of oral hypoglycemic drugs.
Trulicity: A non-insulin injectable medication used to manage blood glucose. It should be coded under Z79.85 for long-term use of injectable non-insulin antidiabetic drugs.

Coding:

Primary Diagnosis:
- E84.9 (Cystic fibrosis, unspecified)
- E08.9 (Secondary diabetes mellitus due to another condition)
Medication Codes:
- Z79.4 (Long-term use of insulin)
- Z79.84 (Long-term use of oral hypoglycemic drugs)
- Z79.85 (Long-term use of injectable non-insulin antidiabetic drugs)

In this example, the coder must accurately capture the underlying condition of cystic fibrosis (E84.9) along with the diagnosis of secondary diabetes (E08.9), and the long-term medication regimen that includes insulin, oral, and injectable hypoglycemics.

Example 3: Temporary Insulin Use in a Type 2 Diabetes Patient During Hospitalization

In this example, the patient from Example 1 (Type 2 diabetes, managed with Metformin and Victoza) was admitted to the hospital for a condition unrelated to diabetes. During the hospitalization, the patient received three doses of insulin to control blood sugar levels.

Since insulin was only used temporarily during the hospitalization (to manage hyperglycemia), it should not be coded as part of the patient’s ongoing medication regimen. The insulin was administered solely to stabilize the patient’s blood glucose levels in response to the hospitalization and was not part of their usual treatment for diabetes.

Coding:

E11.9 (Type 2 diabetes without complications)
Z79.84 (Long-term use of oral hypoglycemic drugs)
Z79.85 (Long-term use of injectable non-insulin antidiabetic drugs)

In this case, although the patient received insulin, it is not coded as Z79.4 (long-term use of insulin), because the use of insulin was temporary and specifically tied to the hospitalization, rather than a permanent part of the patient’s treatment plan. The insulin use during the hospital stay does not require a separate code.

ICD-10-CM Updates (FY 2025):

- New codes for hypoglycemia (E16.A1, E16.A2, E16.A3) for diabetes-related hypoglycemia.

Coding Adverse Effects, Overdosing, and Underdosing:

- Adverse effects from diabetes medications should be coded using the Table of Drugs and Chemicals in ICD-10-CM. Common adverse effects include hypoglycemia, weight gain, nausea, and infections.
- Overdosing: If overdose is unintentional, code with T38.3X1; for intentional overdose, use T38.3X2 or T38.3X3, based on the source.
- Underdosing: If a patient is not taking medication as prescribed (due to financial reasons or other factors), code with T38.3X6.

Coding Insulin Pump Use:

- If an insulin pump is used, it should be coded with Z96.41.
- Malfunctions of insulin pumps should be coded with T85.614.

Takeaways for Accurate Coding:

- Coders should pay attention to details, including the correct use of Z79 codes for diabetes medication.
- Always confirm the type of diabetes, treatment methods, and whether an insulin pump or glucose monitor is involved.
- Ensure accurate coding for adverse effects, overdosing, and underdosing, considering whether the issue is unintentional or intentional.

By following these guidelines, coders can navigate the complexities of diabetes medication coding more efficiently.