Could bone-strengthening exercises and osteoporosis drugs be key to losing weight safely when older?
A $7 million study beginning this summer will help determine if a combination of resistance training and bone-strengthening exercises, coupled with osteoporosis medication or just a targeted drug, can help older adults safely lose weight without sacrificing bone mass.
Shedding weight is recommended to help stave off heart disease and diabetes. But slimming down can increase bone loss and subsequent fracture risk.
The paradox has been a focus for the last decade for Kristen Beavers, an associate professor in the Department of Health and Exercise Science and a principal investigator for the Bone, Exercise, Alendronate, and Caloric Restriction (BEACON) trial at Wake Forest University in North Carolina in the US.
Now she and colleagues from the university and the research institution’s School of Medicine will work together on the study to see what treatment combinations may work best in helping alleviate bone thinning in older people losing weight.
Dr Beavers’ previous work has looked at how resistance training helps offset bone and muscle loss associated with slimming down, and how wearing a weighted vest might help counterbalance the problem while dropping fat.
When a load is applied to bones, through anything from walking to stair climbing, it tells the body to slow the bone loss that occurs naturally with ageing.
Dr Beavers said the addition of a first line osteoporosis drug like alendronate, a bisphosphonate medication which goes by the brand name Fosamax, was the next logical step.
Bisphosphonates are US Food and Drug Administration approved medications that are used to prevent and treat osteoporosis, which is age-related bone loss.
Dr Beavers said the mechanisms driving both age-related and weight reduction bone loss were not dissimilar.
She is hoping that results from the BEACON trial show these drugs can be repurposed to help preserve bone in older adults while they lose weight. reducing the risk of fracture and mortality, as well as improving quality of life.
According to research published in the American Journal of Medicine and the Journal of Bone and Mineral Research, more than half of all adults experiencing a hip fracture end up permanently disabled, with 25% likely to die in the subsequent year.
The new, five-year BEACON study, funded by the National Institutes of Health, coincides with the arrival of state-of-the art technology to Atrium Health Wake Forest Baptist Medical Center.
The technology, called high-resolution peripheral quantitative computed tomography (HRpQCT), is capable of producing detailed images of bone architecture so researchers can tell exactly how each intervention – resistance training with bone-loading exercises, such as hopping, and/or the bisphosphonate, alendronate – affect bone structure during weight loss.
One hypothesis is that the drug will affect trabecular bone. This is found inside the ends of long bones, such as the ankle or wrist. Meanwhile, the bone loading exercises will affect the outer cortical bone. This is the strong, dense material that protects the length of the bone.
Ashley Weaver, associate professor of biomedical engineering at Wake Forest University School of Medicine, said: “In the BEACON study, we have a unique opportunity to see changes in the bone much better with this tool.”
BEACON researchers at both Wake Forest University and the University of Colorado-Anschutz Medical Campus in the US will recruit overweight adults aged 60-plus who already have low bone mass and are not currently taking osteoporosis medication.
All participants will follow a one-year dietary weight loss plan, and then will be subdivided into four groups.
The first will take bisphosphonate alongside resistance training with bone loading exercises. The second group will take just the bisphosphonate, while the third will do resistance training with bone loading exercises only.
The fourth cohort won’t take any bisphosphonate or do any resistance training or bone loading exercises.
In addition to receiving the dietary weight loss programme, all the participants will be encouraged to do about 30 minutes per day of cardiovascular exercise, such as walking.
The interventions will last for a year. Bone-mass assessments will be taken at the beginning and again at six and 12 months. An optional 24-month assessment will help determine how effective the treatment was long term on bone health.
Daniel Beavers, an associate professor in Wake Forest’s Department of Statistical Sciences and the BEACON principal investigator with Kristen Beavers, will monitor the data collected during the study.
He is working with the Division of Public Health Sciences at the medical school to develop a data-capture system that is user friendly and offers a way to easily flag figures that seem unexpected.
“Data collection and monitoring is very important throughout the trial. High-quality data that has been reliably monitored should yield results that are more trustworthy and scientifically valid,” he said.
