Trends in physical functioning in acute lymphoblastic leukemia and non-Hodgkin lymphoma survivors across three decades.

PURPOSE: The impact of changes in therapy for childhood acute lymphoblastic leukemia (ALL) and non-Hodgkin lymphoma (NHL) on the prevalence of physical performance limitations and participation restrictions among survivors is unknown. We aimed to describe the prevalence of reduced function among ALL and NHL survivors by treatment era. METHODS: Participants included survivors of childhood ALL and NHL, and a cohort of their siblings, participating in the Childhood Cancer Survivor Study (CCSS). Physical function was measured using questionnaire. The prevalence of reduced function was compared to siblings using generalized estimating equations, overall and stratified by treatment decade. Associations between organ system-specific chronic conditions (CTCAE v4.03) and function were also evaluated. RESULTS: Among 6511 survivors (mean age 25.9 years (standard deviation 6.5)) and 4127 siblings, risk of performance limitations (15.2% vs. 12.5%, prevalence ratio [PR] = 1.5, 95%CI = 1.3-1.6), restrictions in personal care (2.0% vs. 0.6%, PR = 3.1, 95% CI = 2.0-4.8), routine activities (5.5% vs. 1.6%, PR = 3.6, 95% CI = 2.7-4.8), and work/school attendance (8.8% vs. 2.1%, PR = 4.5, 95% CI = 3.6-5.7) was increased in survivors vs. siblings. The prevalence of survivors reporting reduced function did not decrease between the 1970s and 1990s. The presence of neurological and cardiovascular conditions was associated with reduced function regardless of treatment decade. CONCLUSIONS: Despite changes in therapy, the prevalence of poor physical function remained constant between the 1970s and 1990s. The CCSS clinical trial registration number is NCT01120353 (registered May 6, 2010). IMPLICATIONS FOR CANCER SURVIVORS: Our findings support screening for reduced physical function so that early interventions to improve physical performance and mitigate chronic disease can be initiated.

Design and methods of a randomized telehealth-based intervention to improve fitness in survivors of childhood cancer with exercise intolerance.

BACKGROUND: Exercise intolerance among childhood cancer survivors substantially increases risk for early mortality, reduced cognitive function, poor quality of life, emotional distress, and sub-optimal participation in social roles. Fortunately, exercise intolerance is modifiable, even among individuals with impaired cardiopulmonary and neuromuscular health. This study aims to evaluate the impact of tailored exercise intervention remotely supervised by fitness professionals in survivors with exercise intolerance. Telehealth-based delivery of the intervention aims to enhance uptake by removing the burden of travel and allowing participants to gain confidence with exercise and physical activity at home. METHODS: This is an ongoing single-blind, two-arm, prospective, clinical trial that will randomize 160 participants 1:1 to intervention (n = 80) and attention control (n = 80) groups. The intervention group receives an individually tailored exercise prescription based on results from baseline assessments performed remotely via a Health Insurance Portability and Accountability Act-compliant virtual platform and personal preferences for aerobic exercise. Each prescription includes aerobic and strengthening components designed to progress gradually to 150-300-min of moderate aerobic activity and twice weekly strengthening exercises over 20-weeks. The first two weeks are supervised for 6 sessions, tapering to twice/week for weeks 3-4, once/week for weeks 5-8, every other week for weeks 9-16 and once midway between weeks 17-20. The schedule is modifiable depending on participant need, adherence, and response to exercise. Each session is approximately one hour. CONCLUSION: This study tests the efficacy of an individually prescribed, virtually supervised exercise intervention on exercise intolerant childhood cancer survivors. CLINICALTRIALS: gov registration: NCT04714840.

Cancer-Related Worry as a Predictor of 5-yr Physical Activity Level in Childhood Cancer Survivors.

PURPOSE: Cancer-related worry (CRW; concerns related to cancer and its late effects) is prevalent among childhood cancer survivors. Elevated CRW has been associated with self-reported suboptimal physical activity. The aim of this investigation was to describe associations between CRW and objectively assessed physical activity in childhood cancer survivors. METHODS: CRW was assessed at a baseline evaluation using six survey items. Weekly minutes of moderate and vigorous physical activity were captured by actigraphy 5.25 (3.8-8.0) yr later. Factor analysis was used to identify types of worry; multiple regression determined independent associations between CRW and moderate and vigorous physical activity adjusting for sex, race, diagnosis, age at baseline, anxiety level at baseline, self-reported physical activity at baseline, and pain interference at baseline. RESULTS: Participants ( n = 1223) were an average of 30.9 (SD, 6.9) yr at baseline and 36.1 (SD, 7.1) yr at follow-up. Thirty-seven percent were survivors of leukemia, 26% of non-CNS solid tumors, 19% of lymphoma, 11% of CNS tumors, and 6% of other malignancies. Two types of CRW were identified: "body-focused" and "general fear." Body-focused CRW ( ß = -19.6, P = 0.012), endorsing pain interference ( ß = -27.7, P = 0.002) at baseline, and having a diagnosis of CNS tumor ( ß = -41.3, P = 0.0003) or non-CNS solid tumor ( ß = -19.4, P = 0.02) were negatively associated with physical activity at follow-up. CONCLUSIONS: CRW related to bodily function and appearance is associated with decreased physical activity. Clinicians should consider the potential negative impact of CRW on physical activity levels and provide behavioral counseling.

Health behavior profiles in young survivors of childhood cancer: Findings from the St. Jude Lifetime Cohort Study.

BACKGROUND: There is limited understanding of associations between a combination of health behaviors (physical activity, sedentary/screen-time, diet) and cardiometabolic health risk factors, physical performance, and emotional health among young (<18) childhood cancer survivors (CCS). The aims of this research were to address this gap by 1) deriving health behavior adherence profiles among CCS, and 2) examining associations among demographic, diagnosis and/or treatment exposures, cardiometabolic, physical performance, and emotional functioning with health behavior profile membership. METHODS: Participants included 397 CCS (≥5 years post-diagnosis; 10-17 years old) enrolled in the St. Jude Lifetime Cohort Study who completed physical health evaluations and questionnaires assessing health behaviors and psychological functioning. Latent profile analysis was used to derive profiles of health behavior adherence. Logistic regression and t-tests were used to examine mean-level differences and associations between profile membership with demographic, diagnosis, treatment exposures, cardiometabolic health, psychological functioning, and physical performance. RESULTS: Two profiles emerged: inactive-unhealthy-diet ("IU") and active-sedentary-unhealthy-diet ("ASU") to guidelines. More participants in IU demonstrated higher resting heart rate (mean [M], 76.54; SD = 12.00) and lower motor proficiency scores (M = 34.73; SD = 29.15) compared to ASU (resting heart rate, M = 71.95, SD = 10.74; motor proficiency, M = 50.40, SD = 31.02). CONCLUSIONS: CCS exhibited low adherence to multiple health behavior guidelines, with adherence patterns differentially associated with cardiometabolic health (i.e., resting heart rate) and physical performance. However, robust protection against all health variables was not observed. Findings suggest interventions designed to improve health outcomes should target multiple health behaviors simultaneously. PLAIN LANGUAGE SUMMARY: Pediatric cancer survivors are at-risk for detrimental health outcomes associated with cancer and treatment. Engagement in healthy lifestyle behaviors serves to reduce health vulnerabilities among adult survivors but less is known about associations with lifestyle behaviors on young survivors. This study documents patterns of lifestyle behaviors among survivors of pediatric cancer, factors that increase susceptibility to nonadherence, and associations among lifestyle behaviors and health indicators.

Design and methods of a randomized web-based physical activity intervention among children with cancer: A report from the Children's Oncology Group.

BACKGROUND: Promoting physical activity soon after treatment for childhood cancer may benefit health because sedentary lifestyle during curative therapy may perpetuate physical and emotional complications. The primary goals of this study are to evaluate the effects of a 6-month web-based, rewards-based physical activity intervention on fitness, biomarkers of cardiometabolic health, inflammation, adipokine status, quality of life and school attendance, and determine if effect of intervention on markers of cardiometabolic health is mediated by changes in fitness. The primary outcome of interest is fitness (physiological cost index, six-minute walk test) measured at end of intervention. METHODS: This ongoing study is a two-arm, prospective, randomized design with accrual goals of 192 children for intervention and control groups. Children ≥8 years and < 16 years of age, not meeting recommended levels of physical activity, who completed therapy within the past 12 months are eligible. Both groups receive: 1) educational materials encouraging physical activity, 2) activity monitor, 3) access to web-based interface designed to motivate physical activity, 4) rewards based on physical activity levels, and 5) access to their activity data on the web-interface. Those randomized to intervention: 1) can view others' activity and interact with other participants, and 2) receive rewards based on physical activity levels throughout the intervention (vs. at the end of the intervention for control group). CONCLUSION: Unique, scalable, and portable physical activity interventions that motivate young survivors are needed. This study will inform future web-based physical activity interventions for children with cancer by demonstrating effects of rewards and social interaction. CLINICAL TRIALS: ClinicalTrials.gov Identifier: NCT03223753; COG Identifier: ALTE1631.

Physical function, body mass index, and fitness outcomes in children, adolescents, and emerging adults with craniopharyngioma from proton therapy through five years of follow-up.

PURPOSE: Children diagnosed with craniopharyngioma are vulnerable to adverse health outcomes. Characterization of body mass index (BMI), physical function, and cardiopulmonary fitness in those treated with proton radiotherapy (PRT) will serve to design interventions to improve outcomes. METHODS: Ninety-four children with craniopharyngioma completed physical function testing prior to PRT and annually for 5 years. For each outcome, age- and sex-specific z-scores were calculated using normative values. Participants with z-scores > 1.5 or < - 1.5 were classified as impaired. Those with z-scores > 2.0 or < - 2.0 were classified as significantly impaired. Descriptive statistics were used to describe study outcomes and change in prevalence of impairments from 2 to 5 years after treatment. RESULTS: Nearly half of participants [45.2%, 95% confidence interval (CI) 39.4, 51.0] had mean BMI z-scores > 1.5 at baseline, with prevalence increasing to 66.7% (95% CI 61.5, 71.9) at 5 years. More than half of participants (54.2%, 95% CI 48.4, 60.0) had knee extension strength z-scores < - 1.5 at baseline, with prevalence increasing to 81.3% (95% CI 77.7, 84.9) at 5 years. BMI and knee extension strength had the largest proportion of participants impaired at both 2 and 5 years (53.2% and 62.3%, respectively). Resting heart rate had the highest proportion of participants not impaired at 2 years but became impaired at 5 years (26.6%). CONCLUSIONS: Children with craniopharyngioma have BMI and fitness abnormalities at diagnosis and continue 5 years after treatment. This cohort may benefit from interventions designed to improve BMI, strength, and resting indicators of cardiopulmonary fitness.

Skeletal Muscle and Childhood Cancer: Where are we now and where we go from here.

Skeletal muscle (muscle) is essential for physical health and for metabolic integrity, with sarcopenia (progressive muscle mass loss and weakness), a pre-curser of aging and chronic disease. Loss of lean mass and muscle quality (force generation per unit of muscle) in the general population are associated with fatigue, weakness, and slowed walking speed, eventually interfering with the ability to maintain physical independence, and impacting participation in social roles and quality of life. Muscle mass and strength impairments are also documented during childhood cancer treatment, which often persist into adult survivorship, and contribute to an aging phenotype in this vulnerable population. Although several treatment exposures appear to confer increased risk for loss of mass and strength that persists after therapy, the pathophysiology responsible for poor muscle quantity and quality is not well understood in the childhood cancer survivor population. This is partly due to limited access to both pediatric and adult survivor muscle tissue samples, and to difficulties surrounding non-invasive investigative approaches for muscle assessment. Because muscle accounts for just under half of the body's mass, and is essential for movement, metabolism and metabolic health, understanding mechanisms of injury responsible for both initial and persistent dysfunction is important, and will provide a foundation for intervention. The purpose of this review is to provide an overview of the available evidence describing associations between childhood cancer, its treatment, and muscle outcomes, identifying gaps in current knowledge.

Physiologic Frailty and Neurocognitive Decline Among Young-Adult Childhood Cancer Survivors: A Prospective Study From the St Jude Lifetime Cohort.

PURPOSE: Eight percent of young-adult childhood cancer survivors meet criteria for frailty, an aging phenotype associated with poor health. In the elderly general population, frailty is associated with neurocognitive decline; this association has not been examined in adult survivors of childhood cancer. METHODS: Childhood cancer survivors 18-45 years old (≥ 10 years from diagnosis) were clinically evaluated for prefrailty or frailty (respectively defined as ≥ 2 or ≥ 3 of: muscle wasting, muscle weakness, low energy expenditure, slow walking speed, and exhaustion [Fried criteria]) and completed neuropsychologic assessments at enrollment (January 2008-June 2013) and 5 years later. Weighted linear regression using inverse of sampling probability estimates as weights compared differences in neurocognitive decline in prefrail and frail survivors versus nonfrail survivors, adjusting for diagnosis age, sex, race, CNS-directed therapy (cranial radiation, intrathecal chemotherapy, and neurosurgery), and baseline neurocognitive performance. RESULTS: Survivors were on average 30 years old and 22 years from diagnosis; 18% were prefrail and 6% frail at enrollment. Frail survivors declined an average of 0.54 standard deviation (95% CI, -0.93 to -0.15) in short-term verbal recall, whereas nonfrail survivors did not decline (ß = .22; difference of ßs = -.76; 95% CI, -1.19 to -0.33). Frail survivors declined more than nonfrail survivors on visual-motor processing speed (ß = -.40; 95% CI, -0.67 to -0.12), cognitive flexibility (ß = -.62; 95% CI, -1.02 to -0.22), and verbal fluency (ß = -.23; 95% CI, -0.41 to -0.05). Prefrail and frail survivors experienced greater declines in focused attention (prefrail ß = -.35; 95% CI, -0.53 to -0.17; frail ß = -.48; 95% CI, -0.83 to -0.12) compared with nonfrail survivors. CONCLUSION: Over approximately 5 years, prefrail and frail young-adult survivors had greater declines in cognitive domains associated with aging and dementia compared with nonfrail survivors. Interventions that have global impact, designed to target the mechanistic underpinnings of frailty, may also mitigate or prevent neurocognitive decline.

Progression of Frailty in Survivors of Childhood Cancer: A St. Jude Lifetime Cohort Report.

BACKGROUND: Some adult survivors of childhood cancers develop frailty at higher rates than expected based on their chronological age. This study examined the incidence of frailty among survivors at 10 or more years after diagnosis, frailty prevalence 5 years later, and risk factors for becoming frail. METHODS: Frailty was measured at study entry and 5 years later. Logistic regression tested the associations of several factors with having frailty at 5 years for all participants and separately by sex and by study entry frailty status. Cox models evaluated the hazard of death associated with entry frailty considering covariates. RESULTS: Cancer survivors (range = 0-22 years at diagnosis, median = 7 years) were ages 18-45 years (median = 30 years) at study entry. Frailty prevalence increased from 6.2% (95% confidence interval [CI] = 5.0% to 7.5%) to 13.6% (95% CI = 11.9% to 15.4%) at 5 years. Risk factors for frailty at follow-up among all survivors included chest radiation 20 Gy or higher (odds ratio [OR] = 1.98, 95% CI = 1.29 to 3.05), cardiac (OR = 1.58, 95% CI = 1.02 to 2.46), and neurological (OR = 2.58, 95% CI = 1.69 to 3.92) conditions; lack of strength training (OR = 1.74, 95% CI = 1.14 to 2.66); sedentary lifestyle (OR = 1.75, 95% CI = 1.18 to 2.59); and frailty at study entry (OR = 11.12, 95% CI = 6.64 to 18.61). The strongest risk factor for death during follow-up was prior frailty (OR = 3.52, 95% CI = 1.95 to 6.32). CONCLUSIONS: Prevalent frailty more than doubled at 5 years after study entry among adult childhood cancer survivors. Frailty at entry was the strongest risk factor for death. Because treatment exposures cannot be changed, mitigation of other risk factors for frailty, including lack of strength training and sedentary lifestyle, may decrease risk of adverse health events and improve longevity in survivors.

Physical activity and fitness in childhood cancer survivors: a scoping review.

BACKGROUND: Estimates indicate that nearly eight percent of the over 500,000 survivors of childhood cancer living in the United States are frail in their fourth and fifth decades of life, a phenotype typically seen in geriatric populations. Participation in regular physical activity to improve physical fitness in healthy and diseased populations reduces risk for frail health by increasing physiologic reserve. However, physical activity may not have the same effects on fitness in childhood cancer survivors as it does among their peers with no cancer history. AIMS: This scoping review seeks to describe associations between physical activity, physical fitness, chronic disease, and mortality in childhood cancer survivors. METHODS: Relevant literature was identified through a comprehensive search in the PubMed, Web of Science, CINAHL, and Cochrane databases. A narrative synthesis was performed on observational studies that had physical activity or physical fitness clearly defined and compared with chronic disease outcomes. RESULTS: A total of 595 studies were screened, and results from 11 studies are presented. Childhood cancer survivors who participate in regular physical activity have improved markers of cardiovascular health, decreased risk of overt cardiovascular disease, and decreased risk of all-cause mortality compared to survivors who are not physically active. Childhood cancer survivors who are physically fit have increased neurocognition, and decreased risk of all-cause mortality compared to survivor's who are not fit. The differential effects of physical activity on fitness and health among childhood cancer survivors when compared to peers is potentially related to treatment exposures that damage cardiovascular tissue and impact regenerative potential. CONCLUSION: Research is needed to determine the optimal timing, frequency, intensity, and duration of physical activity necessary to optimize fitness in childhood cancer survivors.

Cardiovascular Family History Increases Risk for Late-Onset Adverse Cardiovascular Outcomes in Childhood Cancer Survivors: A St. Jude Lifetime Cohort Report.

BACKGROUND: Survivors of childhood cancer have an increased risk of therapy-related cardiovascular disease. It is not known whether family history of cardiovascular disease further increases risk of adverse cardiovascular outcomes among survivors. METHODS: Family history of cardiovascular disease was collected from 1,260 survivors [median age at diagnosis, 8 years (range, 0-23); age at last follow-up, 35 years (range, 18-66)] of childhood cancer in the St. Jude Lifetime Cohort Study. Multivariable risk models evaluated associations with cardiovascular disease (Common Terminology Criteria for Adverse Events grade 2-4 events) and cardiovascular risk factors. RESULTS: Among survivors exposed to chest-directed radiation and/or anthracycline chemotherapy (n = 824), 7% reported a first-degree family history of heart failure, 19% myocardial infarction, 11% stroke, 26% atherosclerotic disease (myocardial infarction and/or stroke), 62% hypertension, and 31% diabetes mellitus. Eighteen percent of exposed survivors developed heart failure, 9% myocardial infarction, 3% stroke, 11% atherosclerotic disease, 30% hypertension, and 9% diabetes mellitus. Having a first-degree family history of atherosclerotic disease was independently associated with development of treatment-related heart failure [RR, 1.38; 95% confidence interval (CI), 1.01-1.88; P = 0.04] among exposed survivors. Risk for hypertension was increased among exposed survivors with a first-degree family history of hypertension (RR, 1.55; 95% CI, 1.26-1.92; P < 0.0001) or of any cardiovascular disease [myocardial infarction, stroke, or heart failure (RR, 1.30; 95% CI, 1.06-1.59; P = 0.01)]. CONCLUSIONS: Family history of cardiovascular disease and cardiovascular risk factors independently increased risk of heart failure and hypertension among survivors of childhood cancer exposed to cardiotoxic therapies. IMPACT: These data show the importance of cardiovascular family history as a risk factor for cardiovascular disease in survivors of childhood cancer.

Cardiac biomarkers and association with subsequent cardiomyopathy and mortality among adult survivors of childhood cancer: A report from the St. Jude Lifetime Cohort.

BACKGROUND: Survivors of childhood cancer exposed to cardiotoxic therapies are at significant cardiovascular risk. The utility of cardiac biomarkers for identifying the risk of future cardiomyopathy and mortality is unknown. METHODS: N-terminal pro-B-type natriuretic peptide (NT-proBNP) and cardiac troponin T (cTnT) were assessed in 1213 adults 10 or more years from a childhood cancer diagnosis; 786 were exposed to anthracycline chemotherapy and/or chest-directed radiation therapy (RT). NT-proBNP values above age- and sex-specific 97.5th percentiles were considered abnormal. Generalized linear models estimated cross-sectional associations between abnormal NT-proBNP and anthracycline or chest RT doses as risk ratios with 95% confidence intervals (CIs). A Poisson distribution estimated rates and a Cox proportional hazards model estimated hazard ratios (HRs) for future cardiac events and death. RESULTS: At a median age of 35.5 years (interquartile range, 29.8-42.5 years), NT-proBNP and cTnT were abnormal in 22.5% and 0.4%, respectively. Exposure to chest RT and exposure to anthracycline chemotherapy were each associated with a dose-dependent increased risk for abnormal NT-proBNP (P for trend <.0001). Among exposed survivors with no history of Common Terminology Criteria for Adverse Events-graded cardiomyopathy and with normal systolic function, survivors with abnormal NT-proBNP had higher rates per 1000 person-years of cardiac mortality (2.93 vs 0.96; P < .0001) and future cardiomyopathy (32.10 vs 15.98; P < .0001) and an increased risk of future cardiomyopathy (HR, 2.28; 95% CI, 1.28-4.08) according to a multivariable assessment. CONCLUSIONS: Abnormal NT-proBNP values were prevalent and, among survivors who were exposed to cardiotoxic therapy but did not have a history of cardiomyopathy or current systolic dysfunction, identified those at increased risk for future cardiomyopathy. Further longitudinal studies are needed to confirm this novel finding.

Balance impairment in survivors of pediatric brain cancers: risk factors and associated physical limitations.

PURPOSE: The study aims were to determine the prevalence of balance impairments in adult survivors of pediatric central nervous system (CNS) tumors, and to identify predictors of and limitations associated with balance impairments. METHODS: Participants were adult survivors (N = 329) of pediatric CNS tumors. Balance was considered impaired among those with composite scores < 70 on the sensory organization test. Potential predictors of impaired balance were evaluated with generalized linear regression. Multivariable logistic regression was used to evaluate associations between balance impairment and function. RESULTS: Balance impairment was observed in 48% of survivors, and associated with infratentorial tumor location (OR = 4.0, 95% CI, 2.0-7.6), shunt placement (OR = 3.5, 95% CI, 1.8-6.7), increased body fat percentage (OR = 1.1, 95% CI, 1.0-1.1), hearing loss (OR = 11.1, 95% CI, 5.6-22.2), flexibility limitations (OR = 2.0, 95% CI, 1.0-3.9), peripheral neuropathy (OR = 2.4, 95% CI, 1.2-4.5), and cognitive deficits (OR = 2.2, 95% CI, 1.1-4.7). In adjusted models, impaired balance was associated with limitations in overall physical performance (OR = 3.6, 95% CI, 2.0-6.3), mobility (OR = 2.6, 95% CI, 1.5-4.4), diminished walking endurance (OR = 2.9, 95% CI, 1.7-5.0), and non-independent living (OR = 2.0, 95% CI, 1.0-4.3). CONCLUSIONS: Nearly half of adult survivors of pediatric CNS tumors have impaired balance, which is associated with mobility and physical performance limitations. Interventions to address the complex needs of this population should be prioritized. IMPLICATIONS FOR CANCER SURVIVORS: Survivors with identified risk factors should be closely evaluated for presence of balance impairment. Interventions tailored to improve balance also can positively affect function and mobility in survivors.

Association of Exercise Intolerance With Emotional Distress, Attainment of Social Roles, and Health-Related Quality of Life Among Adult Survivors of Childhood Cancer.

Importance: Exercise intolerance is associated with increased risk for morbidity and mortality in childhood cancer survivors. However, an association between exercise intolerance and psychosocial outcomes has not been fully explored. Objective: To examine the associations between exercise intolerance and emotional distress, attainment of social roles, and health-related quality of life in childhood cancer survivors. Design, Setting, and Participants: A cross-sectional study including 1041 adult survivors of childhood cancer and 286 community controls in the St Jude Lifetime Cohort was conducted at St Jude Children's Research Hospital. The study was performed from April 1, 2012, to March 15, 2020. Exposures: Exercise intolerance was defined as relative peak oxygen uptake less than 85% of age- and sex-estimated levels from maximal cardiopulmonary exercise testing. Main Outcomes and Measures: Emotional distress was measured with the 18-item Brief Symptom Inventory-18, which includes overall Global Severity Index and depression, anxiety, and somatization subscales. Participants with T scores greater than or equal to 63 were classified as having elevated levels of distress. Social attainment was evaluated using patient-reported educational, employment, and marital status. Health-related quality of life was examined with the Medical Outcomes Survey Short Form-36. Participants with T scores less than or equal to 40 were classified as reporting poor health-related quality of life. Results: Of the 1041 participants, 528 were women (50.7%). The prevalence of exercise intolerance among survivors (mean [SD] age, 35.5 [9.2] years) was higher than that among controls (age, 34.5 [10.0] years) (survivors: 634 [60.9%] vs controls: 75 [26.2%], P < .001). After adjusting for age at diagnosis and cardiopulmonary exercise testing, sex, race/ethnicity, smoking, physical activity, and exercise intolerance were associated with an increased risk for anxiety (prevalence rate ratio [PRR], 1.95; 95% 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); an inverse association was noted with having a college degree (PRR, 0.67; 95% CI, 0.50-0.88). Exercise intolerance was associated with an increased the risk for scoring less than or equal to 40 on the physical component summary of the Medical Outcomes Survey Short Form-36 (PRR, 3.69; 95% CI, 2.34-5.84). These associations persisted when either cancer treatment exposures or chronic health conditions were added to the model. Conclusions and Relevance: 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.

Cardiac autonomic dysfunction in survivors of childhood acute lymphoblastic leukemia: The St. Jude Lifetime Cohort Study.

BACKGROUND: Cardiac autonomic dysfunction (CAD) is possible following treatment for childhood cancer. The aims of our analyses were to compare the prevalence of CAD between adult survivors of childhood acute lymphoblastic leukemia and controls, compare exercise response among survivors with and without CAD, and identify treatment-related risk factors for CAD. PROCEDURE: Participants were treated for childhood acute lymphoblastic leukemia at St. Jude Children's Research Hospital between 1980 and 2003 (N = 338). A comparison group matched for race/ethnicity, age, and sex was also recruited (N = 325). Resting heart rate (HR) was assessed via electrocardiogram, and heart rate recovery (HRR) and exercise capacity were evaluated with submaximal cardiopulmonary exercise testing. RESULTS: CAD was present in 33.7% of survivors and 27.6% of controls (P = 0.09). Although mean resting HR did not differ between survivors and controls (74 ± 12 vs 72 ± 12 beats per minute (bpm), P = 0.07), survivors had lower mean HRR than controls (22 ± 9 vs 25 ± 10 bpm; P < 0.001). Survivors with CAD had lower peak exercise tolerance (25.7 ± 6.5 vs 21.2 ± 4.9 mL/kg/min, P < 0.001) than those without. Survivors treated with cyclophosphamide in combination with vincristine ≥38 mg/m2 and/or glucocorticoids ≥10 000 mg/m2 were 1.56 (95% CI 1.09-2.24) times more likely to have CAD than those without this treatment. Obese survivors were 1.78 (95% CI: 1.31-2.40) times more likely to have CAD than nonobese survivors (P < 0.001). CONCLUSION: CAD was present in over one third of survivors and was associated with lower exercise capacity. Obese survivors and those exposed to cyclophosphamide with high doses of vincristine and/or corticosteroids were at greatest risk.

Protein Supplementation and Resistance Training in Childhood Cancer Survivors.

PURPOSE: Muscle weakness, low lean body mass, and poor physical performance are prevalent among adult survivors of childhood cancer (survivors). We evaluated the feasibility and effects of resistance training with and without protein supplementation on lean body mass and muscle strength among survivors. METHODS: This double-blind placebo-controlled trial enrolled survivors ≥18 to <45 yr old. Participants were randomized to resistance training with protein supplement (21 g whey protein per day, 90 kcal) (RT + S) or resistance training with placebo (sucrose, 90 kcal) (RT + P). Participants received educational materials, access to a local fitness center, and a tailored resistance training program with tapered supervision. Participant retention and adherence were used to evaluate feasibility. Lean body mass and muscle strength were assessed at baseline and 24 wk, using dual x-ray absorptiometry, and dynamometer testing or one-repetition maximum testing, respectively. Mean changes were compared with two-way ANOVA. RESULTS: Of 70 participants randomized, 57 completed the 24-wk intervention (24 in RT + S, 33 in RT + P). The RT + S group completed 74.8% and the RT + P group completed 67.0% of exercise sessions. Mean ± SD age for those who completed was 33.1 ± 7.0 yr, 67% were White and 47% female. There were no differences in change in lean mass (RT + S, 1.05 ± 2.34 kg; RT + P, 0.13 ± 2.19 kg; P = 0.10) or strength (grip RT + S, 1.65 ± 4.17 kg; RT + P, 1.63 ± 4.47 kg; P = 0.98; mean leg press RT + S, 58.4 ± 78.8 kg; RT + P, 51.0 ± 65.1 kg; P = 0.68) between groups. Both lean mass (P = 0.03) and strength (grip P = 0.003, leg press P < 0.001) increased over time. CONCLUSIONS: Supervised resistance training among survivors with protein supplementation is feasible but not more effective at increasing total lean body mass than resistance training alone.

The 6-minute walk test is a good predictor of cardiorespiratory fitness in childhood cancer survivors when access to comprehensive testing is limited.

Cardiovascular disease is up to 10 times more likely among childhood cancer survivors compared to siblings. Low cardiorespiratory fitness is a modifiable risk-factor for cardiovascular diseases. Yet, cardiorespiratory fitness is not routinely screened in pediatric oncology, and healthy VO2max cut-points are unavailable. We aimed to predict cardiorespiratory fitness by developing a simple algorithm and establish cut-points identifying survivors' cardiovascular fitness health-risk zones. We recruited 262 childhood cancer survivors (8-18 years old, ≥1-year posttreatment). Participants completed gold-standard cardiorespiratory fitness assessment (Cardiopulmonary Exercise Test [CPET; VO2max ]) and 6-minute walk test (6MWT). Associations with VO2max were included in a linear regression algorithm to predict VO2max , which was then cross-validated. We used Bland-Altman's limits of agreement and Receiver Operating Characteristic curves using FITNESSGRAM's "Healthy Fitness Zones" to identify cut-points for adequate cardiorespiratory fitness. A total of 199 participants (aged 13.7 ± 2.7 years, 8.5 ± 3.5 years posttreatment) were included. We found a strong positive correlation between VO2max and 6MWT distance (r = 0.61, r2 = 0.37, p < 0.001). Our regression algorithm included 6MWT distance, waist-to-height ratio, age and sex to predict VO2max (r = 0.79, r2 = 0.62, p < 0.001). Forty percentages of predicted VO2max values were within ±3 ml/kg/min of measured VO2max . The cut-point for FITNESSGRAM's "health-risk" fitness zone was 39.8 ml/kg/min (males: AUC = 0.88), and 33.5 ml/kg/min (females: AUC = 0.82). We present an algorithm to reasonably predict cardiorespiratory fitness for childhood cancer survivors, using inexpensive measures. This algorithm has useful clinical application, particularly when CPET is unavailable. Our algorithm has the potential to assist clinicians to identify survivors below the cut-points with increased cardiovascular disease-risk, to monitor and refer for tailored interventions with exercise specialists.

Exercise Intolerance, Mortality, and Organ System Impairment in Adult Survivors of Childhood Cancer.

PURPOSE: Exercise intolerance, associated with heart failure and death in general populations, is not well studied in survivors of childhood cancer. We examined prevalence of exercise intolerance in survivors exposed or not to cardiotoxic therapy, and associations among organ system function, exercise intolerance, and mortality. METHODS: Participants consisted of 1,041 people who had survived cancer ≥ 10 years (and had or did not have exposure to anthracyclines and/or chest-directed radiation) and 285 control subjects. Exercise intolerance was defined as peak oxygen uptake < 85% predicted from maximal cardiopulmonary exercise testing; organ functions were ascertained with imaging or clinical testing. Multivariable regression of the data was performed to compare exercise capacity between survivors exposed or unexposed to cardiotoxic therapy and control subjects, and to evaluate associations between treatment and organ function, and organ function and exercise intolerance. Propensity score methods in time-to-event analyses evaluated associations between exercise intolerance and mortality. RESULTS: Survivors (mean age ± standard deviation [SD], 35.6 ± 8.8 years) had lower mean (± SD) peak oxygen uptake (exposed: 25.74 ± 8.36 mL/kg/min; unexposed: 26.82 ± 8.36 mL/kg/min) than did control subjects (32.69 ± 7.75 mL/kg/min; P for all < .001). Exercise intolerance was present in 63.8% (95% CI, 62.0% to 65.8%) of exposed survivors, 55.7% (95% CI, 53.2% to 58.2%) of unexposed survivors, and 26.3% (95% CI, 24.0% to 28.3%) of control subjects, and was associated with mortality (hazard ratio, 3.9; 95% CI, 1.09 to 14.14). Global longitudinal strain (odds ratio [OR], 1.71; 95% CI, 1.11 to 2.63), chronotropic incompetence (OR, 3.58; 95% CI, 1.75 to 7.31); forced expiratory volume in 1 second < 80% (OR, 2.59; 95% CI, 1.65 to 4.09), and 1 SD decrease in quadriceps strength (OR, 1.49; 95% CI, 1.23 to 1.82) were associated with exercise intolerance. Ejection fraction < 53% was not associated with exercise intolerance. CONCLUSION: Exercise intolerance is prevalent among childhood cancer survivors and associated with all-cause mortality. Treatment-related cardiac (detected by global longitudinal strain), autonomic, pulmonary, and muscular impairments increased risk. Survivors with impairments may require referral to trained specialists to learn to accommodate specific deficits when engaging in exercise.

Physical fitness and neurocognitive outcomes in adult survivors of childhood acute lymphoblastic leukemia: A report from the St. Jude Lifetime cohort.

BACKGROUND: Survivors of childhood acute lymphoblastic leukemia (ALL) are at increased risk for both treatment-related exercise intolerance and neurocognitive deficits. This analysis aimed to identify the association between exercise intolerance and neurocognitive impairments in ALL survivors. METHODS: Cardiopulmonary exercise testing, results from a 2-hour standardized neuropsychological assessment, and self-report questionnaires were obtained for 341 adult survivors of childhood ALL and 288 controls. Multivariable modeling was used to test associations between oxygen uptake at 85% estimated heart rate (rpkVO2 ) and neuropsychological test and self-reported questionnaire domains, adjusted for sex, age at diagnosis, cranial radiation, anthracycline, and methotrexate exposure and tobacco smoking status. RESULTS: Compared with controls, survivors had worse rpkVO2 and performance on verbal intelligence, focused attention, verbal fluency, working memory, dominant/nondominant motor speed, visual-motor speed, memory span, and reading and math measures (all P < .001). In adjusted models, exercise intolerance was associated with decreases in performance of verbal ability, focused attention, verbal fluency, working memory, dominant motor speed, nondominant motor speed, visual-motor speed, memory span, reading academics, and math academics in survivors. CONCLUSION: This study demonstrates an association between exercise intolerance and neurocognitive outcomes. Research is needed to determine whether interventions that improve exercise tolerance impact neurocognitive function in ALL survivors.