Heart disease and other cardiovascular diseases (CVD) are frequently associated with comorbidities, which are conditions that appear in conjunction with one another. One such comorbidity is lung cancer, one of the most common forms of cancer.

What Is Heart Disease?

CVD includes heart disease and several other conditions that affect the function of your lungs and heart. CVD affects more than 30 million people in the United States and is one of the leading causes of death among adults.

Most forms of heart disease — including coronary artery disease and peripheral artery disease — are associated with certain lifestyle factors. Those factors can include obesity, smoking, and poor diet. Blood vessel blockages caused by CVD can lead to more serious complications such as a heart attack (myocardial infarction) or stroke.

What Is Lung Cancer?

Lung cancer is diagnosed in more than 235,000 people living in the United States each year. According to the American Cancer Society, it is the second leading cause of cancer death in both men and women.

Lung cancer arises when cells in your lungs grow uncontrollably and form tumors. There are two main types of lung cancer: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC).

Non-Small Cell Lung Cancer

NSCLC is the most common type of lung cancer. It makes up about 85 percent of lung cancer diagnoses in the United States each year. There are multiple subtypes of NSCLC based on what type of cell it forms in, but treatment options are generally similar among those different types.

Small Cell Lung Cancer

Per the American Cancer Society, about 10 percent to 15 percent of Americans with lung cancer have SCLC, the other main type of lung cancer. SCLC tends to be more aggressive (fast-growing) than NSCLC, and it often comes back after treatment.

Who Gets Lung Cancer?

Lung cancer, like heart disease, primarily affects older adults. Tobacco use is the main lifestyle factor that can lead you to have a high risk of lung cancer. If you don’t smoke but are regularly exposed to secondhand smoke, you are also considered at high risk for developing lung cancer. It’s also possible that some high-dose beta-carotene dietary supplements can be a risk factor for smokers, as well as people who are exposed to asbestos.

Other known risk factors for lung cancer include:

• Exposure to radon, asbestos, or other cancer-causing substances
• Exposure to air pollutants
• A family history of lung cancer

Current research indicates that you may be at an increased risk of lung cancer if you have already been diagnosed with heart disease. This seems particularly true in people who’ve experienced heart failure.

Some MyHeartDiseaseTeam members have shared about struggling with both conditions. “Cannot tell if breathing problems are from heart or lungs. Have heart failure and had lung cancer,” wrote one member.

That said, if you experience heart failure, you generally have more X-rays than people without heart failure. And more X-rays mean you stand a better chance of small cell cancers, including lung cancer, being detected earlier. As with most cancers, the earlier you detect it, the sooner you and your health care team can attack your treatment plan.

Can Heart Disease Cause Lung Cancer?

CVD is observed in about 23 percent of people with NSCLC. It can be initially diagnosed in follow-ups for lung cancer treatment. But in many cases, people have already had undetected CVD when they were first diagnosed with lung cancer.

This comorbidity is partly because your risk for both CVD and lung cancer increases with age, so it’s common to find the conditions together. However, some data also suggest that a prior diagnosis with CVD is a risk factor for being diagnosed with lung cancer later.

Another reason for their frequent simultaneous coexistence is that both CVD and lung cancer are affected by some of your body’s same processes. For example, inflammation, your body’s response to cell damage, is involved in the development of both CVD and lung cancer. In addition, smoking — the primary risk factor for lung cancer — is also strongly associated with heart disease.

Getting Treatment for Lung Cancer

People with heart disease are often excluded from clinical trials for cancer therapies. This is because complications of CVD may make it more difficult to evaluate the side effects and efficacy of the treatment. Also, some cancer therapies can be toxic to your already damaged heart.

There is no standard, one-size-fits-all approach for treating lung cancer in people living with heart disease. That’s because there is a general lack of data on the safety of lung cancer treatments in people with heart disease. Rather, lung cancer treatments are prescribed at the discretion of the doctor. In people with CVD, lung cancer is most commonly treated using some combination of chemotherapy and radiation therapy.

Managing Heart Disease and Lung Cancer

There are strategies you can implement to improve your life and outcomes while managing both heart disease and lung cancer. But the best approach is when you can avoid a double diagnosis altogether. If you smoke, quitting is the most effective thing you can do to reduce your risk of ever developing lung cancer alongside your CVD.

Quitting can be difficult for many smokers, as MyHeartDiseaseTeam members have acknowledged. “I need to quit smoking and I haven't been able to yet!!” said one member. While not always easy, when you successfully kick the habit, you not only improve your health, but also you gain a bolstering sense of accomplishment. “It was the hardest thing I accomplished in my life,” said another member. “It can be done, takes determination, but you can do it,” encouraged one member.

Consider adopting other healthy habits to manage your CVD symptoms. Many MyHeartDiseaseTeam members have taken charge of their health in just such a way. “Thank God I've been feeling well, I've changed my eating habits and have been eating more healthy!!” said a member.

If you have been diagnosed with lung cancer, talk with your cardiologist and oncologist about how to maximize your treatment options while avoiding potential complications.

Talk With Others Who Understand

On MyHeartDiseaseTeam, the social network for people with heart disease and their loved ones, 51,000 members come together to ask questions, give advice, and share their stories with others who understand life with heart disease.

Are you living with heart disease and lung cancer? How has one affected the other? Share your experience in the comments below, or start a conversation by posting on MyHeartDiseaseTeam.