A natural history of weight change in men with prostate cancer on androgen-deprivation therapy (ADT): results from the Shared Equal Access Regional Cancer Hospital (SEARCH) database.

OBJECTIVES: • To better understand the natural history of weight change with androgen-deprivation therapy (ADT), we investigated the effect of ADT on body weight among men from the Shared Equal Access Regional Cancer Hospital (SEARCH) database. • Men undergoing ADT lose lean muscle but gain fat mass, contributing to an overall gain in weight. PATIENTS AND METHODS: • We identified 132 men in SEARCH who received ADT after radical prostatectomy. • 'Weight change' was defined as the difference in weight before starting ADT (6 months before ADT) and the on-ADT weight (between 6 and 18 months after starting ADT). • In a subanalysis, baseline characteristics of weight-gainers and -losers were analysed using univariate and multivariate analysis to test association with weight change.
RESULTS: • In all, 92 men (70%) gained weight, and 40 (30%) either lost or maintained a stable weight. • On average, weight on ADT was 2.2 kg higher than the weight before ADT, with the mean change for weight-gainers and -losers being +4.2 kg and -2.4 kg, respectively. • This compared with no significant weight change in the year before starting ADT (paired t-test, change -0.7 kg, P= 0.19) or in the second year on ADT (paired t-test, change -0.5 kg, P= 0.46) for 84 men in whom these additional weight values were recorded. • There was no significant association between any of the features examined and weight change on univariate and multivariate analysis.
CONCLUSION: • In this longitudinal study, ADT was accompanied by significant weight gain (+2.2 kg). This change occurred primarily in the first year of therapy, with men neither losing nor gaining additional weight thereafter.