Weight Loss for Obese Prostate Cancer Patients on Androgen Deprivation Therapy

PURPOSE: Excess fat mass (FM) contributes to poor prostate cancer (PCa) prognosis and comorbidity. However, FM gain is a common side effect of androgen deprivation therapy (ADT). We examined the efficacy of a 12-wk weight loss intervention to reduce FM and maintain lean mass (LM) in ADT-treated obese PCa patients. METHODS: Fourteen ADT-treated obese PCa patients (72 ± 9 yr, 39.7% ± 5.4% body fat) were recruited for a self-controlled prospective study, with 11 completing the 6-wk control period, followed by a 12-wk intervention comprising 300 min·wk(−1) of exercise including supervised resistance training and home-based aerobic exercise, and dietitian consultations advising a daily energy deficit (2100–4200 kJ) and protein supplementation. Body composition was assessed by dual x-ray absorptiometry. Secondary outcomes included muscle strength (one-repetition maximum), cardiorespiratory fitness (maximal oxygen consumption), and blood biomarkers. RESULTS: There were no significant changes during the control period. Patients attended 89% of supervised exercise sessions and 100% of dietitian consultations. No changes in physical activity or energy intake were observed. During the intervention, patients experienced significant reductions in weight (−2.8 ± 3.2 kg, P = 0.016), FM (−2.8 ± 2.6 kg, P < 0.001), and trunk FM (−1.8 ± 1.4 kg, P < 0.001), with LM preserved (−0.05 ± 1.6 kg, P = 0.805). Muscle strength (4.6%–24.7%, P < 0.010) and maximal oxygen consumption (3.5 ± 4.7 mL·min(−1)·kg(−1), P = 0.041) significantly improved. Leptin significantly decreased (−2.2 (−2.7 to 0.5) ng·mL(−1), P = 0.016) with no other changes in blood biomarkers such as testosterone and lipids (P = 0.051–0.765); however, C-reactive protein (r(s) = −0.670, P = 0.024) and triglycerides (r = −0.667, P = 0.025) were associated with individual changes in LM. CONCLUSIONS: This study shows preliminary efficacy for an exercise and nutrition weight loss intervention to reduce FM, maintain LM, and improve muscle strength and cardiorespiratory fitness in ADT-treated obese PCa patients. The change in body composition may affect blood biomarkers associated with obesity and PCa progression; however, further research is required.