NEW YORK (Reuters Health) – Lean body mass (LBM) declines significantly among men on androgen-deprivation therapy (ADT) for prostate cancer, a new prospective study confirms.
And while the decline was sharpest when men started ADT, it continued for up to 36 months of treatment, according to Dr. Matthew R. Smith of the Massachusetts General Hospital Cancer Center in Boston and his colleagues.
At all time points, men 70 and older showed a steeper drop in LBM than younger men.
“Men receiving this treatment should be advised about the potential side effects, and although the optimal strategy to mitigate body composition changes has not been demonstrated yet, we know enough from the general population to recommend that men have a healthy diet and exercise regimen,” Dr. Smith told Reuters Health. “Resistance training should be part of that program for our patients.”
While some small, single-center studies have linked sarcopenia to ADT, “the long-term effects of ADT on LBM and patient characteristics associated with LBM changes in men with prostate cancer are not well characterized,” said Dr. Smith and his colleagues in the Journal of Clinical Oncology, in a report online May 29.
Their new findings are from a prespecified substudy of 252 participants in a randomized controlled trial of denosumab for fracture prevention. All were on ADT for non-metastatic prostate cancer, and all were assessed with dual-energy x-ray absorptiometry at baseline and at 12, 24, and 36 months.
On average, LBM declined by 1% at 12 months, 2.1% at 24 months, and 2.4% at 36 months (p<0.001 for all). Among the 127 men who were at least 70 years old, LBM had declined by 2.8% by 36 months, compared to 0.9% for the younger men (p=0.035).
Men who had been on ADT for six months or less at the beginning of the study showed a trend toward a sharper decline in LBM compared to men who had been on ADT for a longer period (3.7% vs 2.0%; p=0.06).
Sarcopenia has serious health consequences, Dr. Smith noted in an interview, especially for older men who are already at risk for frailty. “The clinical consequences are concerning,” he said. “There are many hundreds of thousands of men in the United States currently receiving this treatment.”
He and his colleagues are now planning to investigate the effects of muscle loss on function. “We’d like to quantify those effects to better understand the functional consequences of muscle loss and ultimately develop effective strategies to mitigate this problem,” he said.
J Clin Oncol 2012.