UCSF/Baylor team uses new method to measure bone loss in astronauts flying lo...( A team of NASA-funded researchers from ...),Health

Study results appear in the online version of the Journal of Bone and Mineral Research, which can be viewed at http://www.jbmr-online.org.

The researchers used three-dimensional x-ray computed tomography [CT] to study the effect of prolonged weightlessness on the bone mineral density and structure of the hip in a group of 14 American and Russian crew members making flights of four-to six-month duration on the International Space Station (ISS).

This study is the first to use CT imaging to three-dimensionally quantify spaceflight-related bone loss in the hip and to estimate changes in hip bone strength. Previous studies have used a two-dimensional imaging technology called dual x-ray absorptiometry (DXA).

"Our study demonstrates that bone loss, especially from the central skeleton, occurs in the ISS crewmembers at a rate comparable to that observed almost a decade before in the crew of the Russian MIR spacecraft," said Thomas Lang, PhD, UCSF associate professor of radiology and principal investigator on the study.

"The lack of clear progress in the interval between the MIR and ISS missions indicates a need for continued efforts to improve musculoskeletal conditioning regimens during longer space missions, such as those proposed for the moon and Mars."

He added that pharmacological interventions, such as drug therapies that suppress the accelerated bone resorption which is associated with weightlessness, are being evaluated by other NASA-funded researchers as aids to prevent bone loss during long-duration space travel.

The researchers also analyzed loss of density in vertebrae, or back bones, which, along with the hip, are the skeletal sites associated most with serious osteoporotic fractures in the elderly.
'"/>

Contact: Maureen McInaney
mmcinaney@pubaff.ucsf.edu
415-476-2557
University of California - San Francisco
8-Mar-2004