Sexual dimorphism modulates the impact of cancer cachexia on lower limb muscle mass and function

Background & aims: There is a sparsity of data on the impact of cachexia on human muscle function. This study examined the relationship between cachexia, quality of life and the mass/function/mechanical quality of lower limb skeletal muscle in gastrointestinal cancer patients. Methods: Quadriceps strength and lower limb power were measured in 54 patients with gastrointestinal cancer (n ¼ 24 10% weight-loss) and 18 healthy controls. Quadriceps cross-sectional area was measured in 33/54 patients and in all controls using MRI. Muscle mechanical quality was defined as quadriceps strength/unit quadriceps cross-sectional area. Quality of life was assessed using the EORTC QLQ-C30. Patients with weight-loss 10% were classified as cachectic. Results: In male cachectic patients, quadriceps strength (p ¼ 0.003), lower limb power (p ¼ 0.026), quadriceps cross-sectional area (p ¼ 0.019) and muscle quality (p ¼ 0.008) were reduced compared with controls. In female cachectic patients, quadriceps strength (p ¼ 0.001) and muscle quality (p ¼ 0.001) were reduced compared with controls. Physical function (p ¼ 0.013) and fatigue (p ¼ 0.004) quality of life
scores were reduced in male cachectic compared with non-cachectic patients, but not in females. Conclusions: Muscle quality is reduced in cancer patients. The degree of impairment of lower limb muscle mass, quality and function and the impact on quality of life varies with weight-loss and sex.