In a study reported in JAMA Oncology, Hayek et al found that exercise intolerance was more common among adult survivors of childhood cancer than among matched controls and that it was associated with a greater likelihood of emotional distress, poorer attainment of social roles, and poorer health-related quality of life.

Study Details

The cross-sectional study included 1,041 adult survivors of childhood cancer and 286 community controls matched for age, sex, and race/ethnicity in the St. Jude Lifetime Cohort. The study was conducted at St. Jude Children’s Research Hospital between April 2012 and March 2020.

Exercise intolerance was defined as relative peak oxygen uptake of less than 85% of age- and sex-estimated levels from maximal cardiopulmonary exercise testing. Emotional distress was assessed using the 18-item Brief Symptom Inventory-18, which includes a global severity index and depression, anxiety, and somatization subscales; elevated distress level was defined as a T score ≥ 63. Social attainment was evaluated using patient-reported educational, employment, and marital status. Health-related quality of life was assessed using the Medical Outcomes Survey Short Form-36 (SF-36), with a T score ≤ 40 indicating poorer health-related quality of life.

Key Findings

Mean age of survivors and controls at time of evaluation was 35.5 years and 34.5 years.

Exercise intolerance was found in 60.9% of survivors vs 26.2% of controls (P < .001).

In analysis adjusting for age at diagnosis and cardiopulmonary exercise testing, sex, race/ethnicity, smoking status, and physical activity, exercise intolerance vs no exercise intolerance among survivors was associated with increased risk for anxiety (prevalence rate ratio [PRR] = 1.95, 95% confidence interval [CI] = 1.20–3.16), somatization (PRR = 1.86, 95% CI = 1.23–2.80), and unemployment (PRR = 1.76, 95% CI = 1.23–2.52), and reduced likelihood of having a college degree (PRR = 0.67, 95% CI = 0.50–0.88).

After adjustment for age at diagnosis and cardiopulmonary exercise testing, race/ethnicity, smoking status, and physical activity, survivors with exercise intolerance were more likely to have a T score ≤ 40 in the SF-36 physical function (PRR =  5.54, 95% CI = 3.20–9.53), role physical (PRR = 2.62, 95% CI = 1.74–3.94), bodily pain (PRR = 2.14, 95% CI =1.43–3.22), general health (PRR = 2.31, 95% CI = 1.65­–3.23), role emotional (PRR =  1.86, 95% CI = 1.21–2.87), and social function (PRR = 1.79, 95% CI = 1.20–2.68) subscales and on the physical component summary (PRR = 3.69, 95% CI, 2.34–5.84).

The observed associations persisted in analyses in which cancer treatment exposures or chronic health conditions were added to the model.

The investigators concluded, “The findings of this study suggest that exercise intolerance is independently associated with emotional distress, attainment of social roles, and health-related quality of life of long-term survivors of childhood cancer. The results also suggest that improving physiologic capacity may benefit general health and wellness, as well as emotional health, ability to participate in social roles, and health-related quality of life.”

Kirsten K. Ness, PhD, of the Department of Epidemiology and Cancer Control, St. Jude Children’s Research Hospital, is the corresponding author for the JAMA Oncology article.

Disclosure: The study was supported by grants from the National Cancer Institute and by the American Lebanese-Syrian Associated Charities. For full disclosures of the study authors, visit jamanetwork.com.