Wadey Curtis A, Barker Alan R, Stuart A Graham, Dorobantu Dan-Mihai, Pieles Guido E, Tran Derek L, Laohachai Karina, Ayer Julian, Weintraub Rob G, Cordina Rachael, Williams Craig A
Children's Health & Exercise Research Centre (CHERC) Public Health and Sports Sciences, Faculty of Health and Life Sciences, University of Exeter Exeter United Kingdom.
Research and Improvement Hampshire and Isle of Wight Healthcare NHS Foundation Trust Hampshire United Kingdom.
J Am Heart Assoc. 2024 Dec 17;13(24):e034944. doi: 10.1161/JAHA.123.034944. Epub 2024 Dec 14.
Peak oxygen consumption (peak O) is traditionally scaled by body mass, but it is most appropriately scaled by fat-free mass. However, it is unknown whether peak O scaled by fat-free mass is associated with mortality and morbidity in people with a Fontan circulation. The aim of this study was to assess the associations between different expressions of peak O with mortality and morbidity in people with a Fontan circulation.
Eighty-seven participants (aged 24.1±7.3 years; 53% women) with a Fontan circulation completed a cardiopulmonary exercise test and a dual-energy x-ray absorptiometry scan. Cox proportional hazard regressions models assessed the association (hazard ratio [HR]) between different expressions of peak O with a composite outcome of Fontan failure (FF). Participants were followed up for a median of 6.5 years (95% CI, 6.4-6.9). Individuals experiencing FF (n=10/87) had a significantly lower absolute peak O. In univariable models, peak O ratio scaled to body mass was not significantly associated with FF (HR, 0.91; =0.111). However, peak O scaled by fat-free mass (HR, 0.90; =0.020) or lean mass (HR, 0.90; =0.017) was significantly and inversely associated with FF. These associations remained significant after adjusting for age, sex, and peak respiratory exchange ratio.
The association between peak O and FF is improved when scaled to measures of body composition. Applied clinically, a 1-unit increase in peak O scaled to fat-free mass or lean mass is associated with a ≈10% lower risk of FF.
传统上，最大摄氧量（peak O₂）是按体重进行标化的，但最恰当的标化方式是按去脂体重。然而，对于接受Fontan循环手术的患者，按去脂体重标化的peak O₂是否与死亡率和发病率相关尚不清楚。本研究的目的是评估不同表达方式的peak O₂与接受Fontan循环手术患者的死亡率和发病率之间的关联。
87名接受Fontan循环手术的参与者（年龄24.1±7.3岁；53%为女性）完成了心肺运动试验和双能X线吸收法扫描。Cox比例风险回归模型评估了不同表达方式的peak O₂与Fontan循环衰竭（FF）复合结局之间的关联（风险比[HR]）。参与者的中位随访时间为6.5年（95%CI，6.4 - 6.9）。发生FF的个体（n = 10/87）的绝对peak O₂显著更低。在单变量模型中，按体重标化的peak O₂比值与FF无显著关联（HR，0.91；P = 0.111）。然而，按去脂体重标化的peak O₂（HR，0.90；P = 0.020）或瘦体重标化的peak O₂（HR，0.90；P = 0.017）与FF显著负相关。在调整年龄、性别和峰值呼吸交换率后，这些关联仍然显著。
当按身体成分指标进行标化时，peak O₂与FF之间的关联得到改善。在临床应用中，按去脂体重或瘦体重标化的peak O₂每增加1个单位，FF风险约降低10%。
