People with lung cancer may also be affected by a disease called diabetes mellitus, more commonly known as diabetes. Diabetes is one of several possible lung cancer comorbidities, or conditions that may occur alongside lung cancer.

Having both diabetes and lung cancer may impact your treatment options, chance of survival, and quality of life, so it’s important to understand more about how these conditions connect.

What Is Diabetes?

Diabetes is caused by an inability to correctly process blood sugar, called glucose. Glucose, the main form of energy in cells, is formed when the body breaks down carbohydrates from your diet.

The levels of glucose in the blood are controlled by a hormone called insulin, which is made by the pancreas. Typically, insulin helps convert glucose to energy and decreases levels of glucose in the blood. However, a person with diabetes does not make enough insulin or doesn’t respond to it properly. This leads to high levels of glucose in the blood (hyperglycemia) and can cause complications, such as kidney disease and nerve damage.

Types of Diabetes

There are multiple forms of diabetes mellitus:

• Type 1 diabetes is believed to be an autoimmune condition that is diagnosed most commonly in children and young adults.
• Type 2 diabetes develops over the course of several years and is the most prevalent form of diabetes.
• Gestational diabetes is a condition that arises during pregnancy.

In type 2 diabetes, which affects 90 percent to 95 percent of those with diabetes mellitus, the pancreas initially produces insulin, but the body develops insulin resistance. This means that the body does not respond to insulin as it should, so blood glucose levels remain high.

Who Gets Diabetes?

Type 2 diabetes is more likely to be diagnosed in people who are 45 and older. It is also more common in people who are “African American, Alaska Native, American Indian, Asian American, Hispanic/Latino, Native Hawaiian, or Pacific Islander,” according to the National Institute of Diabetes and Digestive and Kidney Diseases. There are many risk factors for developing type 2 diabetes, including:

• Being overweight or obese
• Having a history of heart disease or stroke
• Having high blood pressure (hypertension)
• Having high levels of fat in the blood
• Not being physically active
• Having a family history of diabetes

People who have a history of gestational diabetes during pregnancy or a gynecological condition called polycystic ovarian syndrome are also at an increased risk for developing diabetes.

Understanding the Connection Between Diabetes and Lung Cancer

Diabetes is among the conditions that commonly co-occur with lung cancer. One study of 110 people undergoing surgery for stage 1 non-small cell lung cancer (NSCLC) found that nearly 21 percent also had diabetes. In addition, diabetes has been identified as a potential risk factor for developing NSCLC that requires surgery, although the exact relationship is not well understood.

Impact of Diabetes on Lung Cancer Treatment

Preexisting conditions such as diabetes can impact the treatment regimen for lung cancer. Steroids, a common treatment for the nausea that accompanies chemotherapy, can affect blood glucose levels. Consequently, people with diabetes may need to adjust their insulin levels to account for the impact of steroids on blood sugar.

For newer lung cancer therapies, people with diabetes may not be able to participate in clinical trials, which often have very strict requirements for entry. This makes it difficult to understand how a person with diabetes may respond to treatment. A health care provider should take into account a person’s overall health status when determining treatment options.

Impact of Diabetes on Lung Cancer Survival

One study published in 2017 found that people with lung cancer and diabetes had decreased overall survival compared to those without diabetes. One possible reason for this may be that the high levels of insulin in the blood (hyperinsulinemia) caused by diabetes may contribute to cancer progression. However, more research is needed to better understand how diabetes affects lung cancer survival.

Managing Diabetes and Lung Cancer

You may be able to improve your lung cancer prognosis by effectively managing your diabetes. People with type 2 diabetes can regulate their blood glucose levels by making healthy lifestyle changes through diet and physical exercise. Medication, including insulin therapy and metformin, can also help to manage diabetes.

Talk to your doctor about strategies to manage diabetes and maximize treatment options for lung cancer if you’re living with both conditions.

Talk With Others Who Understand

MyLungCancerTeam is the social network for people with lung cancer and their loved ones. Members come together to ask questions, give advice, and share their stories with others who understand life with lung cancer.

Are you living with lung cancer and diabetes? Share your experience in the comments below, or start a conversation by posting on your Activities page.