Quantitative assessment of cardiorespiratory fitness, skeletal muscle function, and body composition in adults with primary malignant glioma

BACKGROUND: The study was undertaken to evaluate cardiorespiratory fitness, skeletal muscle function, and body composition of patients with newly diagnosed and untreated, postsurgical primary malignant glioma. METHODS: By using a cross-sectional design, patients with clinically stable (10±7 days postsurgery) high-grade glioma (HGG; n=25) or low-grade glioma (LGG; n=10) were studied. Participants performed a cardiopulmonary exercise test (CPET) with expired gas analysis to assess cardiorespiratory fitness (peak oxygen consumption, VO_2peak). Other physiological outcomes included skeletal muscle cross-sectional area (CSA; magnetic resonance imaging), isokinetic muscle strength (isokinetic dynamometer), and body composition (air displacement plethysmography). Quality of life was assessed with the Functional Assessment of Cancer Therapy-Brain scale. RESULTS: CPET was a feasible and safe procedure to assess VO_2peak, with no serious adverse events. VO_2peak indexed to total body weight and lean body mass (LBM) for both groups was 13.0 mL·weight·min^-1 and 19 mL·LBM·min ^-1, the equivalent to 59% and 38% below age- and sex-predicted normative values, respectively. Skeletal muscle strength and mid-thigh CSA were lower in HGG relative to LGG patients (83 vs 125 Nm, P = .025; 94 vs 119 cm ², P = .171, respectively). Skeletal muscle isokinetic strength, CSA, and body composition outcomes predicted VO_2peak (r = -0.59 to 0.68, P < .05). CONCLUSIONS: Postsurgical glioma patients have markedly reduced cardiorespiratory fitness, isokinetic strength, and CSA. Prospective studies are now required to determine whether such abnormalities influence treatment toxicity and clinical outcome as well as to test the effect of appropriately selected interventions to prevent and/or mitigate dysfunction.