Purpose: To compare the prevalence and severity of orthostatic intolerance in survivors of childhood cancer and in healthy controls, and to correlate results of self-reported measures of health status with orthostatic testing in survivors of childhood cancer.
Patient and methods: Thirty-nine survivors of childhood cancer and 56 controls were recruited for this study. Each cancer survivor completed standardised self-report measures and all participants underwent a standing test (5 min supine, 10 min of motionless standing leaning against a wall, followed by another 2 min supine). The main outcomes of the standing test were orthostatic tachycardia (OT), defined as a heart rate increase of at least 30 beats per minute (bpm) during standing, and neurally mediated hypotension (NMH), defined as a drop in systolic blood pressure of at least 25 mmHg.
Results: OT developed in 22/39 (56%) cancer survivors versus 17/56 (30%) controls (P=.01). Cancer survivors had a higher baseline and maximum standing heart rate (both P<.001) and a more rapid onset of significant OT (P=.005). No significant difference in scores on self-report measures was found between cancer survivors with or without OT.
Conclusion: This study provides preliminary evidence of a higher rate of orthostatic intolerance in childhood cancer survivors. Further study is warranted to better define whether this is a modifiable risk factor for fatigue in this population, and how orthostatic intolerance interacts with other known risk factors for lowered quality of life.