Because Type 2 diabetes weakens the bone in often undetectable ways, both directly and indirectly via treatment side effects, experts urged increased awareness….
Henrik Groop, MD, DMSc, of the University of Helsinki, Finland, told reporters at a press conference at the European Association for the Study of Diabetes meeting that, fracture risk has gained attention as a complication of the thiazolidinediones, but bone complications remain under-recognized in diabetes overall.
Peter Vestergaard, MD, PhD, of Aarhus University Hospital in Aarhus, Denmark, explained that, “One big part of the problem is the ‘invisible’ damage… Before you are able to do something about a problem you need to be aware that it’s there.”
Typically, osteoporosis can be monitored through progressively declining bone mineral density. But Vestergaard’s research has revealed greater structural frailty of bone in diabetes than expected for a given level of bone mineralization.
“When you measure in diabetics, their bone may look like normal bone at least under the scanners we use nowadays,” he said at the press conference. “However, it fractures.” The biomechanical problems with bones in diabetes patients aren’t fully understood yet, but the collagen that give bone its flexibility appears to be implicated, Vestergaard noted.
“But it seems like the glucose in a way ‘caramelizes’ the bone,” he explained at the press conference.
Standard DEXA scanners currently can’t pick up these issues, so Vestergaard and other researchers are considering bone biopsy and 3D scanners to figure out how to reinterpret standard diabetic scans.
Another route being explored to explain the interaction is a hormone called osteocalcin which appears to be a way in which bone affects diabetes, as Patricia F. Ducy, PhD, of Columbia University in New York City, discussed at the press conference. This hormone is made exclusively in bone then goes through the blood to the pancreas where it increases beta cell proliferation and insulin levels, thereby improving insulin sensitivity. “Bone is not only a receiver but a giver,” she explained.
Osteocalcin may be a new molecule that could be exploited in the treatment of diabetes, she suggested, noting animal model studies that show benefits of osteocalcin administration.
“It is a long way from the lab to the clinic but it is a pathway we should at least investigate,” she said.
Of course, diabetes treatments can also influence bone complications — namely fracture — indirectly through hypoglycemia as especially elderly patients are at risk of falls when glucose levels get too low, added Matteo Monami, MD, PhD, of the University of Florence, Italy.
“We have to consider bone fractures among treatment outcome for choice of hyperglycemic treatment options,” especially for postmenopausal women, who are already at elevated risk, he said at the press conference.
Groop PH, et al “Diabetes and the bone” EASD 2010.