Exercise Reduces the Risk of Frailty-Related Bone Fractures in Cancer Survivors

What Is Frailty?

Frailty is a complex geriatric (old-age) syndrome characterized by increased vulnerability to minor stressors, leading to adverse health outcomes. It corresponds to the English term “frailty”.

Frailty is common in people of advanced age and those with certain diseases; it is also a factor indicating an increased risk of death. Cancer patients who carry out everyday activities and remain ambulatory may seem far removed from frailty, but the risk still exists, and frailty may lead to further functional decline and even death.

Frail individuals are at high risk of disability, falls, admission to a hospital or care home, and death. Often perceived as a condition specific to aging individuals, it deserves particular attention in oncology because chronological age is a poor reflection of physiological age.

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The Most Comprehensive Study of Frailty in Cancer

According to data from more than 100 thousand people, cancer survivors who followed physical activity/exercise recommendations had a lower risk of frailty-related fractures than those who exercised less.

In her presentation at the annual meeting of the American College of Sports Medicine, Dr. Erika Rees-Punia of the American Cancer Society said, "Frailty-related fractures are more than a broken bone".

Rees-Punia said that older adults have an increased risk of death for 10 years after a fracture.

Cancer itself and cancer treatments are associated with an increased risk of frailty-related bone fractures. However, the role of factors such as physical activity in modifying fracture risk in cancer survivors had remained unclear because previous studies were small and restricted to particular cancer types.

The study group included 101,543 participants, including 14,159 cancer survivors. At the start of the study in 1999, participants' mean age was 69.5; 55% were women and 97.9% were White.

Participants were divided into three categories: short-term survivors (1-5 years after diagnosis), long-term survivors (5 years or more after diagnosis), and those with no history of cancer.

The researchers assessed hazard ratios for overall fracture risk and the effects of both weight training and moderate- to vigorous-intensity aerobic physical activity. Moderate-to-vigorous exercise was defined as moderate to brisk walking or its equivalent.

During the study period, the researchers identified 14,196 frailty-related fractures, including hip, wrist and vertebral fractures.

Short-term survivors (1-5 years) after a cancer diagnosis had a 28% higher risk of frailty-related fractures than people without cancer. Long-term survivors (>5 years) after diagnosis had an 8% higher fracture risk than those without cancer. Both increases were statistically significant.

Looking at site-specific fractures, short-term survivors had a 24% higher risk of pelvic fractures (bones of the groin-hip region) and a 33% higher risk of wrist fractures than people without cancer. These were also statistically significant.

However, long-term survivors who followed recommendations for moderate-to-vigorous aerobic physical activity and weight training had a lower total fracture risk than those who did not.

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A limitation of the study was that participants were predominantly White. Other limitations included cancer type, stage and time since diagnosis.

However, the large study group and long-term follow-up of participants were strengths that reinforced the results.

The researchers said that most participants preferred walking as their physical activity, but more research was needed to better determine the activity type (swimming, cycling, walking, strength training), its role in preventing fractures and the intensity of exercise.

Rees-Punia said, "Future research will explore the role of physical activity across the lifespan." Meanwhile, the conclusion was that patients with cancer should be referred to doctors specializing in exercise, and cancer survivors should be referred to doctors for clinical guidance on preventing fractures and for physical activity.

Physical Activity to Reduce Fracture Risk

Lee Stoner said, "As we age, fractures become a major concern, especially as a result of falls. Falls are among the 20 most costly medical conditions and the leading cause of traumatic brain injury in people aged 65 and older.".

However, previous research shows that fracture risk can be reduced through exercise, so the findings of the current study were not surprising. What is surprising is the limited attention paid to exercise, considering that 5-year cancer survival rates continue to rise…

Stoner said that the key message of this study for doctors was the increased risk of frailty-related fractures in cancer survivors compared with people without cancer. "This risk falls to 8% at 5 years after diagnosis. We know that both aerobic and resistance exercise reduce fracture risk in the general population, and this risk reduction is just as effective in cancer survivors" he emphasized.

The authors did not report whether they adjusted for age. Future research would benefit from clarifying how much risk is related to cancer, how much to age, and how much can be attributed to lifestyle before and during cancer treatment.