Robyn E. Partin

Effect of Low-Magnitude, High-Frequency Mechanical Stimulation on BMD Among Young Childhood Cancer Survivors: A Randomized Clinical Trial

IMPORTANCE Bone accrual during youth is critical to establish sufficient strength for lifelong skeletal health. Children with cancer may develop low bone mineral density (BMD) any time before or after diagnosis. OBJECTIVE To evaluate the ability of low-magnitude, high-frequency mechanical stimulation to enhance BMD among childhood cancer survivors. DESIGN, SETTING, AND PARTICIPANTS Double-blind randomized clinical trial conducted at St Jude Childrens Research Hospital from June 1, 2010, to January 22, 2013, using cancer survivors, ages 7 to 17 years, who were previously treated at St Jude Childrens Research Hospital, were in remission, and at least 5 years from diagnosis, with whole-body or lumbar spine BMD z scores of -1.0 or lower. Participants were randomized (stratified by sex and Tanner stage) to either a placebo device or low-magnitude, high-frequency mechanical stimulation device, which was used at home. INTERVENTIONS Placebo or low-magnitude, high-frequency mechanical stimulation (0.3 g; 32-37 Hz) for 2 sessions lasting 10 minutes each, 7 days per week for 1 year. All participants were prescribed daily cholecalciferol (vitamin D) and calcium. MAIN OUTCOMES AND MEASURES Changes in areal and volumetric BMD and bone biomarkers were compared by analysis of variance, adjusted for strata. RESULTS Of the 65 participants, 32 were randomized to the intervention group (mean [SD] age was 13.6 [3.7] years, 18 [56.2%] were male, and 27 [84.4%] were white), and 33 were randomized to the placebo group (mean [SD] age was 13.6 [2.9] years, 17 [51.5%] were male, and 26 [78.8%] were white). Forty-eight participants completed the trial, 22 in the intervention group and 26 in the placebo group with median adherence of 70.1% for intervention and 63.7% for placebo groups. With intention-to-treat analysis, mean (SD) whole-body BMD z score by dual x-ray absorptiometry improved by 0.25 (0.78) in the intervention (n = 22), but decreased by -0.19 (0.79) in the placebo group (n = 26, P = .05). Circulating osteocalcin at 12 months correlated with change in total body BMD (r = 0.35, P = .02). Tibial trabecular bone among participants completing 70% or more of the prescribed sessions increased by a mean of 11.2% (95% CI, 5.2 to 17.2%) compared with those completing less than 70% who decreased by a mean of -1.3% (95% CI, -7.3 to 4.7%; P = .02). Change in circulating receptor activator of nuclear factor κ-B ligand was higher in the intervention than in the placebo group (0.06 [0.16] vs -0.04 [0.17] pmol/L) (P = .04). CONCLUSIONS AND RELEVANCE Pediatric cancer survivors with low BMD may benefit from low-magnitude, high-frequency mechanical stimulation as a novel and safe intervention to optimize peak bone mass during youth, alone or in conjunction with other therapies. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01010230.

Dietary Protein Intake and Lean Muscle Mass in Survivors of Childhood Acute Lymphoblastic Leukemia: Report From the St. Jude Lifetime Cohort Study.

Background Survivors of childhood acute lymphoblastic leukemia (ALL) are at risk for low lean muscle mass and muscle weakness, which may contribute to inactivity and early development of chronic diseases typically seen in older adults. Although increasing protein intake, in combination with resistance training, improves lean muscle mass in other populations, it is not known whether muscular tissue among survivors of ALL, whose impairments are treatment-related, will respond similarly. Objective The aim of this study was to evaluate associations among dietary protein intake, resistance training, and lean muscle mass in survivors of ALL and age-, sex-, and race-matched controls. Design This was a cross-sectional study. Methods Lean muscle mass was determined with dual-energy x-ray absorptiometry, dietary information with 24-hour recalls, and participation in resistance training with a questionnaire. Participants were 365 survivors of ALL (52% male; 87% white; median age=28.5 years, range=23.6–31.7) and 365 controls with no previous cancer. Results Compared with controls, survivors of ALL had lower lean muscle mass (55.0 versus 57.2 kg, respectively) and lower percentage of lean muscle mass (68.6% versus 71.4%, respectively) than controls. Similar proportions of survivors (71.1%) and controls (69.7%) met recommended dietary protein intake (0.8 g/kg/d). Survivors (45.4%) were less likely to report resistance training than controls (53.8%). In adjusted models, 1-g higher protein intake per kilogram of body mass per day was associated with a 7.9% increase and resistance training ≥1×wk, with a 2.8% increase in lean muscle mass. Limitations The cross-sectional study design limits temporal evaluation of the association between protein intake and lean muscle mass. Conclusions The findings suggest that survivors of childhood ALL with low lean muscle mass may benefit from optimizing dietary protein intake in combination with resistance training. Research is needed to determine whether resistance training with protein supplementation improves lean muscle mass in survivors of childhood ALL.

Clinical impact of sedentary behaviors in adult survivors of acute lymphoblastic leukemia: A report from the St. Jude Lifetime Cohort study: Sedentary Behaviors in Survivors of Leukemia

Sedentary behaviors are associated with poor health outcomes in the general population, but their clinical impact on adult survivors of childhood acute lymphoblastic leukemia (ALL) has not been characterized to date. In the current study, we described the prevalence of sedentary behaviors in survivors of ALL and examined associations between time spent sedentary and body composition and onset of cardiovascular disease (CVD) risk factors.

Influence of fitness on health status among survivors of acute lymphoblastic leukemia

We aimed to determine the prevalence of self‐reported adverse health status among childhood acute lymphoblastic leukemia (ALL) survivors and to identify associations between components of physical fitness and health status.

Physical fitness in survivors of childhood Hodgkin lymphoma: A report from the St. Jude Lifetime Cohort

There are limited data describing fitness and associated health‐related quality of life (HRQoL) in survivors of childhood Hodgkin lymphoma (HL).

Randomized web-based physical activity intervention in adolescent survivors of childhood cancer

Healthy lifestyle choices, including participation in regular physical activity, may improve health outcomes in survivors of childhood cancer. We aimed to evaluate the efficacy of a web‐delivered physical activity intervention among adolescent survivors to increase moderate to vigorous physical activity (MVPA) and improve fitness and neurocognitive and health‐related quality of life (HRQoL) over 24 weeks.

Peripheral Neuropathy, Sensory Processing, and Balance in Survivors of Acute Lymphoblastic Leukemia

Purpose To compare peripheral nervous system function and balance between adult survivors of childhood acute lymphoblastic leukemia (ALL) and matched controls and to determine associations between peripheral neuropathy (PN) and limitations in static balance, mobility, walking endurance, and quality of life (QoL) among survivors. Patients and Methods Three hundred sixty-five adult survivors of childhood ALL and 365 controls with no cancer history completed assessments of PN (modified Total Neuropathy Score [mTNS]), static balance (Sensory Organization Test [SOT]), mobility (Timed Up and Go), walking endurance (6-minute walk test), QoL (Medical Outcomes Study 36-Item Short Form Survey), and visual-motor processing speed (Wechsler Adult Intelligence Scale). Results PN, but not impairments, in performance on SOT was more common in survivors than controls (41.4% v 9.5%, respectively; P < .001). In multivariable models, higher mTNS scores were associated with longer time to complete the Timed Up and Go (β = 0.15; 95% CI, 0.06 to 0.23; P < .001), shorter distance walked in 6 minutes (β = -4.39; 95% CI, -8.63 to -0.14; P = .04), and reduced QoL (β = -1.33; 95% CI, -1.79 to -0.87; P < .001 for physical functioning; β = -1.16; 95% CI, -1.64 to -0.67; P < .001 for role physical; and β = -0.88; 95% CI, -1.34 to -0.42; P < .001 for general health). Processing speed (β = 1.69; 95% CI, 0.98 to 2.40; P < .001), but not mTNS score, was associated with anterior-posterior sway on the SOT. Conclusion PN in long-term ALL survivors is associated with movement, including mobility and walking endurance, but not with static standing balance. The association between processing speed and sway suggests that static balance impairment in ALL survivors may be influenced by problems with CNS function, including the processing of sensory information.

Attainment of Functional and Social Independence in Adult Survivors of Pediatric CNS Tumors: A Report From the St Jude Lifetime Cohort Study

Purpose Beyond survival, achieving independence is a primary goal for adult survivors of pediatric CNS tumors. However, the prevalence of and risk factors for failure to achieve independence, assessed with multiple concurrent indicators, have not been examined. Patients and Methods Functional and social independence was assessed in 306 survivors (astrocytoma [n = 130], medulloblastoma [n = 77], ependymoma [n = 36], and other [n = 63]; median current age, 25.3 years [range, 18.9 to 53.1 years]; time since diagnosis, 16.8 years [range, 10.6 to 41.8 years]). Six observed indicators were used to identify latent classes of independence, which included employment, living independently, assistance with personal care, assistance with routine needs, obtaining a drivers license, and marital status. Physical performance impairments were defined as scores < 10th percentile on measures of aerobic capacity, strength, flexibility, balance, mobility, and adaptive function. Multinomial logistic regression estimated odds ratios (ORs) and 95% CIs were calculated for associations of disease/treatment exposures and impairments in physical performance with nonindependence. Results Three classes of independence were identified as independent (40%), moderately independent (34%), and nonindependent (26%). In multivariable models, craniospinal irradiation (OR, 4.20; 95% CI, 1.69 to 10.44) and younger age at diagnosis (OR, 1.24; 95% CI, 1.14 to 1.35) were associated with risk of nonindependence versus independence. Beyond impaired IQ, limitations in aerobic capacity (OR, 5.47; 95% CI, 1.78 to 16.76), flexibility (OR, 3.66; 95% CI, 1.11 to 12.03), and adaptive physical function (OR, 11.54; 95% CI, 3.57 to 37.27) were associated with nonindependence versus independence. Nonindependent survivors reported reduced physical but not mental health-related quality of life compared with independent survivors. Conclusion Sixty percent of survivors of pediatric CNS tumors do not achieve complete independence as adults. Reduction in intensity of primary therapies and interventions that target physical performance and adaptive deficits may help survivors to achieve greater independence.