Sustained exercise may lower postmenopausal fracture risk
MedWire News: Study results suggest that a long-term exercise program may aid fracture prevention in postmenopausal women, but more data are needed to confirm these findings, say researchers.
Wolfgang Kemmler (University of Erlangen, Germany) and colleagues determined the effect of 12 years of continuously supervised exercise on overall fracture number and bone mineral density (BMD) in 44 women who were 1-8 years postmenopause and had evidence of osteopenia. A group of 41 women who did not change their lifestyle acted as controls.
The researchers found that the risk for fracture was approximately 70% lower among women in the exercise group compared with the control group, but the small sample size meant that the findings were of borderline significance (p=0.074).
The exercise intervention consisted of two 60-minute group training sessions per week, which incorporated aerobic and resistance exercises, and two 20-minute home training sessions per week, while calcium and vitamin D supplementation was provided for both groups.
During the study period, 12 (27%) women in the control group sustained a fracture, compared with four (10%) in the exercise group, giving a nonsignificant risk ratio of 0.32.
Fracture number also differed between both groups, with 19 fractures in the control group versus six fractures in the exercise group, to give a rate ratio of 0.38, which was also nonsignificant.
"Obviously our sample size was still too small to determine significant effects," Kemmler and co-authors remark in the journal Osteoporosis International.
In spite of this, the team found that the change in BMD over the study period at lumbar spine and femoral neck was significantly lower in the exercise group compared with the control group, at -0.8% versus -4.0%, and -3.7% versus -6.7%, respectively.
"Although definite evidence of positive impact of exercises on fractures per se cannot be provided at the present, we strongly encourage elderly subjects to perform multipurpose exercise programs that affect fall risk and bone strength," write the researchers.
"To bridge the current lack of evidence, multicenter approaches with subjects exposed to high fall risks and with low bone density should be performed to generate enough statistical power to definitely determine the effect of exercise on fracture risk," they conclude.
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2011
By Laura Dean