Weight Loss for Obese Prostate Cancer Patients on Androgen Deprivation Therapy.

Abstract

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. 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. 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 (rs = -0.670, P = 0.024) and triglycerides (r = -0.667, P = 0.025) were associated with individual changes in LM. 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.