Abstract

Childhood cancer survivors (CCS) experience short- and long-term side effects from cancer treatment that often impair functional capacity. Inspiratory muscle weakness is a potential mechanism for reduced functional capacity. The objective of this pilot study was to examine the relationship between inspiratory muscle strength and functional capacity in 10 CCS. Inspiratory muscle strength was measured by maximal inspiratory pressure (MIP) while functional capacity was measured by the two-minute walk test (2MWT), the physiological cost index and hemodynamic response to exercise according to changes in heart rate, blood pressure and rate-pressure product (RPP). Overall, MIP and 2MWT distance were below predicted values. Hemodynamic responses to the 2MWT were consistent with little variation, except for elevated diastolic blood pressure (DBP) response. MIP had significant relationships with resting DBP (Spearman’s rank correlation coefficient [r_s] = −0.70; p = 0.03) and DBP response (r_s = 0.72; p = 0.02). Time since completion of cancer treatment had a significant positive relationship with RPP response (r_s = 0.67; p = 0.03). Inspiratory muscle weakness in childhood cancer could be an indicator of skeletal muscle dysfunction and should be considered when symptoms of dyspnea or poor functional capacity arise. Inspiratory muscle strength was found to be related to changes in blood pressure in CCS. Future studies should further investigate these relationships and the impact of inspiratory muscle training on hemodynamics and functional capacity in CCS.

摘要

儿童癌症幸存者 (CCS) 会经历癌症治疗的短期和长期副作用，这些副作用通常会损害功能能力。吸气肌无力是功能能力降低的潜在机制。这项初步研究的目的是检查 10 个 CCS 中吸气肌力量和功能能力之间的关系。吸气肌力量通过最大吸气压力 (MIP) 测量，而功能能力通过两分钟步行试验 (2MWT) 测量，根据心率、血压和心率压力的变化对运动的生理成本指数和血流动力学反应进行测量产品（RPP）。总体而言，MIP 和 2MWT 距离低于预测值。除了舒张压 (DBP) 反应升高外，对 2MWT 的血流动力学反应几乎没有变化。r _s ] = -0.70；p  = 0.03）和 DBP 响应（r _s = 0.72；p  = 0.02）。癌症治疗完成后的时间与 RPP 反应呈显着正相关（r _s = 0.67；p  = 0.03）。儿童癌症中的吸气肌无力可能是骨骼肌功能障碍的一个指标，当出现呼吸困难症状或功能能力差时应予以考虑。发现吸气肌力量与 CCS 中的血压变化有关。未来的研究应进一步研究这些关系以及吸气肌训练对 CCS 血流动力学和功能能力的影响。