Study Updates

Genetic changes, treatments, and lifestyle choices can predict cancer survivors’ risk of severe obesity and other health problems

Adult childhood cancer survivors have a higher risk than the general population for obesity (being extremely overweight) as they age. Obesity can cause health problems such as high blood pressure, diabetes, and heart disease.

For some survivors, genes passed down from their parents increase obesity risk. Scientists looked for genetic differences in 2,548 cancer survivors treated at St. Jude. Some of the survivors were obese and some were not. Scientists used this information to create a genetic risk score (GRS) that measures a survivor’s risk for severe obesity when the GRS details are combined with other data about treatment, smoking and exercise.

The scientists verified their GRS on a larger group of 6,064 survivors at other hospitals. The score identified those who were at high risk for severe obesity.

By using a GRS in survivors, persons at risk for obesity could get interventions to prevent obesity before it starts. This could lower their risk of other problems that often accompany obesity.

Along with obesity, cancer treatments can cause health problems known as late effects. They happen months or years after treatment is over. Scientists collected details about survivors' cancer treatments, how much they exercised, and if they smoked. When this information was combined with the survivors’ GRS, scientists identified 4.3 times more survivors at high risk for severe obesity.

Details about genetic changes, treatments, and lifestyles can identify those at risk for health problems. Both care providers and patients need this information.

• Providers can use health screenings to identify patients and monitor their health.
• High-risk survivors can make lifestyle changes to lower their risk for obesity and other health problems.

What does this mean for you?

As a childhood cancer survivor, know your risks and take action to stay healthy. Here are some things you can do:

• Ask if your cancer treatments could increase your risk for health problems.
• Discuss your survivorship care plan with your primary care provider.
• Get regular health check-ups and screenings.
• Follow your health care provider’s instructions for healthy living, including eating a healthy diet, exercising, and avoiding smoking.
• Take care of yourself to help lower your risk for obesity and related health problems as you age.

Reference:

Sapkota Y, Qiu W, Dixon SB, Wilson CL, Wang Z, Zhang J, Leisenring W, Chow EJ, Bhatia S, Armstrong GT, Robison LL, Hudson MM, Delaney A, Yasui Y. Genetic risk score enhances the risk prediction of severe obesity in adult survivors of childhood cancer. Nat Med. 2022 Aug;28(8):1590-1598. Read the paper

Cancer survivors' access to resources affects their health

Cancer survivors who have access to care and need treatment live longer than those who do not. But there are things people can do to improve their access to care.

Scientists looked at health records from 9,440 people in the St. Jude LIFE study who were at least 5 years or more past treatment. The scientists looked to see if survivors had chronic health conditions such as:

• High cholesterol
• High blood pressure
• Diabetes
• Too thin
• Obesity
• Low bone minerals leading to weak bones
• Low sex hormones
• Low thyroid hormone
• Low adrenal hormones

The scientists also studied the lifestyles of 3,407 other survivors. They looked at how much alcohol the survivors drank, their weight, how much they exercised, and their energy levels. They also looked at where the survivors lived and if those areas had the right health care and resources available.

In general, cancer survivors had a 7.6 times greater chance of living a shorter life. People with chronic health conditions had lower survival if they had less muscle mass, were more easily tired, had low energy, or were weak and/or lived in areas where there were not enough resources. The more chronic health conditions they had, the lower their survival.

Many chronic health conditions can be treated with the right health care. More studies are planned to help survivors lead longer, healthier lives. This includes studying why some survivors have a hard time getting care, treatment, and resources to manage chronic health problems and support a healthy lifestyle.

Study sheds light on how cancer treatment affects heart function

A recent St. Jude LIFE study helps scientists better understand how cancer treatments affect heart function.

Normally, blood enters the top chambers of the heart when the muscles there are relaxed (known as diastole). When the heart does not relax and fill up properly, it is called diastolic dysfunction. This can lead to heart failure.

Researchers did not know how often diastolic dysfunction happened in childhood cancer survivors. Researchers know that cancer medicines called anthracyclines or radiation treatment to the chest can cause cardiac (heart) late effects. Late effects are health problems that happen months or years after treatment is over. Anthracyclines and radiation can damage the heart muscle.

St. Jude LIFE researchers studied the heart function of 3,342 adult survivors of childhood cancer. The scientists used a heart test called an echocardiogram to provide details about heart function. This was the largest study of diastolic dysfunction in childhood cancer survivors done to date.

Scientists found that diastolic dysfunction was the main cause of heart late effects in 9% of childhood cancer survivors.

This work is important because people with diastolic dysfunction have a poorer prognosis and lower survival. Finding ways to diagnose this condition will help care providers give the right treatment to patients at the right time.