Reduced Lower Body Muscular Strength and Endurance among Adult Survivors of Childhood Cancer

Abstract

Introduction: Impaired physical fitness is a possible late effect among adult survivors of childhood cancer (ASCC). Our study describes lower body muscular strength and endurance among ASCC using the 1-min sit-to-stand (1-min STS) test, compares them with the general population, identifies risk factors, and describes changes over time.

Methods: In a prospective multicenter cohort study, we invited ASCC ≥18 yr of age at study who were diagnosed between ages 0 and 20 yr, treated in five pediatric oncology centers across Switzerland from 1976 to 2017, and survived ≥5 yr for a 1-min STS test. We collected information about lifestyle, medical history, and previous cancer treatment. Using population-based Swiss reference values, we calculated age- and sex-adjusted z -scores for 1-min STS performance and assessed the association between risk factors and 1-min STS test using multivariable linear regression. We fitted a multilevel linear model to describe the longitudinal course of 1-min STS performance.

Results: We included 338 CCS of 1048 invited ASCC (participation rate 32%) with a median age at study of 34 yr (interquartile range, 26-41 yr). Compared with the general population, mean 1-min STS z -score was half a standard deviation lower (-0.52; 95% confidence interval (CI), -0.64 to -0.40). Obesity ( B = -0.56; 95% CI, -0.97 to -0.16), cumulative cisplatin dose ( B = -0.12; 95% CI, -0.21 to -0.02), and cumulative cranial radiotherapy dose ( B = -0.10; 95% CI, -0.19 to -0.01) were associated with reduced 1-min STS performance. There was no change in 1-min STS z -scores over time ( B = 0.02; 95% CI, -0.05 to 0.09).

Conclusions: We found evidence for reduced lower body strength and endurance among ASCC, suggesting the need for counseling and effective training and rehabilitation programs for maintaining daily functioning, improving cardiovascular health, and reducing morbidity for ASCC.

FIGURE 1

Flowchart of the study population. N, number. ^aDefined as having received anthracyclines and/or heart-relevant radiotherapy (27).

FIGURE 2

Distribution of 1-min STS z-scores in N = 338 ASCC who underwent baseline assessment on a half violin plot. The box plot below shows the median and IQR of the 1-min STS z-scores.

FIGURE 3

Spaghetti plot of 1-min STS z-scores in N = 67 ASCC who received cardiotoxic treatment with either anthracyclines and/or heart-relevant radiotherapy and who attended 1–3 follow-up visits after baseline examination.