Reduced muscle strength and functional performance in men with prostate cancer undergoing androgen suppression: a comprehensive cross-sectional investigation

Abstract

This study examined the effects of androgen suppression therapy (AST) on upper and lower body muscle strength and a range of direct measures of physical performance using a cross-sectional design with 118 men (48 men undertaking AST for prostate cancer and 70 healthy aged-matched controls) from a single tertiary center. Primary end points included muscle strength for the upperand lower-body; functional performance-repeated chair rise, usual and fast 6-m walk, 6-m backwards walk and 400-m walk time; and dual-energy X-ray absorptiometry assessment-whole body, regional soft tissue composition and bone mineral density (BMD). Men on AST had significantly reduced muscle strength for the upper-and lower-body and impaired functional performance compared to controls (Po0.05). As expected, AST patients had significantly lower whole-body and hip BMD and higher percent of body fat than controls (Po0.05), and tended to have lower whole-body lean mass (À2.3 kg, P ¼ 0.077). Appendicular skeletal muscle was positively associated with upper-body (r ¼ 0.400-0.606, Po0.001) and lower-body (r ¼ 0.549-0.588, Po0.001) muscle strength, and strength was related to functional performance. Men undertaking AST were consistently impaired across a broad range of physical and functional musculoskeletal performance assessments compared with their age-matched normal controls. These findings are relevant for those patients considering AST for subclinical disease management, but whose physical reserve is marginal. Strategies to counter these adverse effects of AST need to be initiated so that independent living and quality of life can be maintained.

Body Composition, Physical Fitness, Functional Performance, Quality of Life, and Fatigue Benefits of Exercise for Prostate Cancer Patients: A Systematic Review

“…So even though only a few significant improvements in body composition were observed, the relative maintenance or slight improvement in these measures would appear of clinical benefit when compared to the significant declines observed during ADT with no exercise 22,23 . Clinically, this may allow a maintenance/increase in muscular strength and functional performance 69 as well reduce the risk of developing metabolic syndrome 15,16 and experiencing falls-related fractures 19 .…”

“…This lack of interest in assessing muscular strength, muscular endurance and functional performance was a little surprising on two counts. This being the importance of these measures for maintaining overall quality of life especially when using ADT 69 and as home-based exercise can significantly improve these outcomes in low-active older adults 75,79,80 . It is therefore recommended that future studies examine the potential for home-based exercise to improve prostate cancer patients' physical fitness and functional performance.…”

“…Results of this review showed that resistance, aerobic and combined resistance and aerobic training all had Level A or B grade evidence for improving physical fitness, functional performance, quality of life and fatigue in prostate cancer patients. This was a little surprising as resistance training would theoretically appear to offer the greatest benefits due to the adverse effects of ADT on body composition, muscular strength/endurance and functional performance 22,23,26,27 . On closer inspection of the data, the apparently similar level of evidence for resistance and aerobic exercise did not always reflect similar magnitudes of effect.…”

“…As the majority of men with prostate cancer are over 65 years of age 2 , these ADT-related changes in body composition may be of additional concern and contribute to the premature development of sarcopenia, frailty and osteoporosis 24 . These changes in body composition and significant fatigue [10][11][12] may then contribute to significant reductions in many measures of physical fitness and functional performance [25][26][27] . For example, compared to age-matched controls [26][27][28][29] , prostate cancer patients on ADT may have 24% less muscular strength, 7% less aerobic fitness and have 20-27% less functional performance ability in repeated chair rise and walking tests, respectively.…”

“…These changes in body composition and significant fatigue [10][11][12] may then contribute to significant reductions in many measures of physical fitness and functional performance [25][26][27] . For example, compared to age-matched controls [26][27][28][29] , prostate cancer patients on ADT may have 24% less muscular strength, 7% less aerobic fitness and have 20-27% less functional performance ability in repeated chair rise and walking tests, respectively. Such losses are of major clinical significance as the prostate cancer patients on ADT possess the physical fitness and functional performance ability of someone 10-20 years older 30 .…”