Introduction
Androgen deprivation therapy (ADT) forms the cornerstone in the treatment of (locally) advanced prostate cancer (PCa). However, ADT is accompanied by numerous adverse health effects. In the present study we assessed the impact of the first 5 months of ADT on body composition, muscle strength, and cardiorespiratory fitness in PCa patients.

Methods
Thirty-four PCa patients (age: 70±7 y) starting ADT were included in the study. Patients underwent baseline measurements upon initiation of ADT and follow-up measurements were performed 5 months later. Measurements consisted of anthropometrics and whole-body dual-energy x-ray absorptiometry to assess changes in body composition, computed tomography scanning of the upper leg to assess changes in leg lean mass, one-repetition maximum (1RM) tests on the leg press and leg extension machines to assess changes in leg muscle strength, and maximal cardiopulmonary exercise testing to assess changes in cardiorespiratory fitness. Data were analyzed with Student’s paired t tests.

Results
Over time, body mass index increased from 26.4±3.6 to 27.0±3.7 kg/m2; P<0.05. Appendicular skeletal muscle mass decreased from 24.4±3.1 to 23.9±3.0 kg; P<0.05. Whole-body fat mass increased from 26.2±7.7 to 28.4±8.3 kg; P<0.001. Quadriceps cross-sectional area decreased from 66.3±9.1 to 65.0±8.5 cm2; P<0.05. 1RM leg press decreased from 107±27 to 100±27 kg; P<0.05, and 1RM leg extension decreased from 52±15 to 48±16 kg; P<0.05. Peak oxygen uptake decreased from 23.2±3.7 to 20.3±3.4 mL/kg body mass/min; P<0.001.

Conclusion
In PCa patients, a strong decrease in skeletal muscle mass, leg strength, cardiorespiratory fitness, and an increase in fat mass was seen after 5 months of ADT. Exercise interventions are required to offset these negative side effects and preserve quality of life in PCa patients.