McGing Jordan J, Serres Sébastien, Nicholas Rosemary, Gupta Ayushman, Radford Shellie J, Nixon Aline V, Mallinson Joanne, Bradley Christopher, Bawden Stephen, Francis Susan T, Greenhaff Paul L, Moran Gordon W
Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, United Kingdom.
Faculty of Medicine and Health Sciences, University of Nottingham, Nottingham, United Kingdom.
J Crohns Colitis. 2025 Jan 11;19(1). doi: 10.1093/ecco-jcc/jjae194.
Inflammatory bowel disease (IBD) fatigue aetiology is poorly understood. This study quantified body composition and physical function alongside proton magnetic resonance imaging (1H MRI) and spectroscopy (31P MRS) measures of organ structure and function in quiescent Crohn's disease patients (CD) and healthy volunteers (HVs), to identify a physiological basis for IBD fatigue.
Body composition was determined using dual-energy X-ray absorptiometry and 1H MRI. Knee extensor isometric strength and isokinetic fatigue were measured using dynamometry. 1H MRI was used to quantify cardiac output, cerebral blood flow (gmCBF), and brain oxygen extraction fraction (OEF) at rest, and during supine, steady-state exercise, and recovery. 31P MRS was used to quantify post-exercise muscle phosphocreatine (PCr) resynthesis.
Sixteen CD and 12 HV (age, sex, and BMI matched) were recruited. Fatigue perception was greater (13.9 ± 1 vs 8.3 ± 0.9, P = .001), and daily step count was less (5482 ± 684 vs 8168 ± 1123, P = .04) in CD. During steady-state exercise, gmCBF was less in CD (653 ± 30 vs 823 ± 40 mL/min, P = .003). Cardiac output and brain OEF were no different. Post-exercise PCr resynthesis was less in CD (17.2 ± 2.0 vs 25.3 ± 2.4 mM·min-1, P = .02). Body composition, isometric strength, and isokinetic fatigability were no different.
CD self-reported increased fatigue perception and exhibited a slower rate of post-exercise PCr resynthesis compared to HV. This occurred independently of changes in body composition, muscle strength, and fatigability. IBD fatigue may be linked to peripheral muscle deconditioning and lower gmCBF during submaximal exercise.
炎症性肠病（IBD）疲劳的病因尚不清楚。本研究对静止期克罗恩病患者（CD）和健康志愿者（HV）的身体成分和身体功能进行了量化，并结合质子磁共振成像（1H MRI）和波谱分析（31P MRS）对器官结构和功能进行了测量，以确定IBD疲劳的生理基础。
使用双能X线吸收法和1H MRI测定身体成分。使用测力计测量膝关节伸肌等长力量和等速疲劳。1H MRI用于在静息状态、仰卧位稳态运动和恢复过程中量化心输出量、脑血流量（gmCBF）和脑氧摄取分数（OEF）。31P MRS用于量化运动后肌肉磷酸肌酸（PCr）的再合成。
招募了16名CD患者和12名HV（年龄、性别和BMI匹配）。CD患者的疲劳感知更强（13.9±1 vs 8.3±0.9，P = 0.001），每日步数更少（5482±684 vs 8168±1123，P = 0.04）。在稳态运动期间，CD患者的gmCBF更低（653±30 vs 823±40 mL/min，P = 0.003）。心输出量和脑OEF没有差异。CD患者运动后PCr再合成更少（17.2±2.0 vs 25.3±2.4 mM·min-1，P = 0.02）。身体成分、等长力量和等速疲劳性没有差异。
与HV相比，CD患者自我报告的疲劳感知增加，且运动后PCr再合成速率较慢。这一现象独立于身体成分、肌肉力量和疲劳性的变化。IBD疲劳可能与次最大运动期间外周肌肉失适应和较低的gmCBF有关。
