A cancer therapy -- considered to be gold-standard treatment -- is causing men to lose muscle mass and gain fat, putting them at increased risk of other disorders like cardiovascular disease, diabetes and osteoporosis, a study has found.
Researchers from Deakin University in Australia showed men treated with hormone therapy for prostate cancer often had a dangerously high fat to muscle ratio. The study said while the five-year survival rate for Australian men with prostate cancer was now 95 per cent, side-effects from the intense treatment regimen were becoming an increasing concern.
"Men diagnosed with prostate cancer are now living longer due to medical advancements, but are susceptible to a range of treatment side-effects," said Patrick Owen, lead author of the study published in the Journal of Cachexia, Sarcopenia and Muscle.
"Prostate cancer survivors are now more likely to die from other conditions, such as cardiovascular disease, than prostate cancer, which may in part be due to our inability to detect and subsequently treat side-effects of therapy," Owen said in a statement. "It's critical we are able to quickly and easily identify modifiable risk factors for these other conditions," he said.
"The amount of muscle we have relative to fat is one of the biggest indicators for diabetes risk, decreased physical function needed to complete daily tasks, and lots of other adverse health conditions," he added.
The research examined the muscle and fat in 70 men treated with hormone therapy for prostate cancer compared to 52 men with prostate cancer not treated with hormone therapy and 70 healthy men of a similar age.
It found men treated with hormone therapy for prostate cancer had the same amount of total muscle mass compared to other men in the study, but four to six kilograms more fat mass. "When muscle was considered in relation to this fat mass, men treated with hormone therapy for prostate cancer had lower fat-adjusted muscle mass, which may predispose them to further health issues," Owen said.
"When men are diagnosed with advanced prostate cancer they are often treated with hormone therapy to reduce their testosterone levels, which discourages cancer growth. This is considered the gold-standard of treatment," he said. "It puts men through the equivalent of menopause.
There's a loss of muscle and bone, they gain fat, and even start to have hot flushes," he said. While men with prostate cancer treated with hormone therapy may have the same or greater absolute muscle mass than non-treated and healthy men, it's not as functional as the same amount of muscle in otherwise healthy weight men.
Owen said he hoped his research would encourage more clinicians to test their patients for muscle mass relative to body fat. Lifestyle interventions that could be used to help men with prostate cancer reduce body fat and increase muscle.
"Given the current treatment and medical landscape, people are living longer with cancer, so there needs to be a shift in focus towards improving the quality of these additional years of living," Owen said.