A healthy lifestyle may reduce mortality risk in adult survivors

An analysis of childhood cancer survivors by St. Jude scientists shows that while adult survivors of childhood cancer experience four times the risk of death as compared to that of the general population, steps can be taken to reduce that risk. Published in The Lancet, the St. Jude analysis showed that survivors have a 20% lower mortality risk when they practice a healthy lifestyle. Mitigating factors included maintaining a healthy weight through diet and exercise, eschewing smoking, and minimal alcohol consumption.

Survivors with hypertension or diabetes had a significantly higher mortality rate than survivors without those conditions. However, these conditions are also modifiable through healthy lifestyle changes and effective treatments from physicians.

Treatments for pediatric cancers have improved, vastly increasing survival and reducing toxicity. More than 85% of U.S. patients are effectively cured of their primary tumor after treatment. This increased success has led to a growing survivor population reaching adulthood.

This study used data from the Childhood Cancer Survivor Study (CCSS), a national collaborative housed at St. Jude. By comparing the data from thousands of CCSS participants to that from the public, the investigators found that even decades after anti-cancer treatment, survivors experience four times the expected mortality risk of the general population.

“We identified that long-term survivors of childhood cancer are experiencing a rate of death above what would be expected for the general aging population,” explained first and corresponding author Stephanie Dixon, MD, MPH, Department of Oncology. “We were the first to find that these excess deaths are predominantly due to the same leading causes of death as in the general population, including second cancers, heart disease, cerebrovascular disease or stroke, chronic liver and kidney disease, and infectious causes of death, experienced at a younger age and higher rate in childhood cancer survivors.”

The CCSS is the largest cohort of childhood cancer survivors in North America, representing an estimated 20% of survivors in that region. The researchers used this cohort’s vast data to isolate variables affecting survivor mortality statistically. Their work demonstrated that even when common confounders, such as sociodemographic features, were controlled for, the gap between survivors and the public persisted — but so did the protective effects of a healthy lifestyle.

“Independent of prior treatment and sociodemographic factors, a healthy lifestyle and absence of cardiovascular risk factors, such as hypertension and diabetes, were associated with reduced health-related mortality risk,” said Dixon. “This suggests that while continued efforts to reduce treatment intensity and improve five-year survival are needed, future research should also focus on tailoring interventions for modifiable lifestyle and cardiovascular risk factors to survivors to reduce chronic disease development and extend their lifespans.”