New study shows that post menopausal women with diabetes have more chance of hip bone fracture compared to women without diabetes. However, bone loss in the spine is slower in people with diabetes than in people without diabetes, according to findings presented at American Society for Bone and Mineral Research, 31st Annual Meeting.

The study by Naila Khalil, PhD,( lead author of the study and postdoctoral research associate with the Department of Community Health, Lifespan Health Research Center, at Wright State University in Kettering, Ohio) looked at data for 2245 multiethnic women, between the ages of 42 and 52 years, participating in the Study of Women's Health Across the Nation (SWAN) at 5 research centres in the United States between 1996 and 2004.

At baseline, women with diabetes had a total hip mean BMD that was 14% higher (P < .01) than those without diabetes, and a lumbar spine BMD that was 9% higher (P < .01); levels of the bone resorption biomarker urinary N-telopeptide of type 1 collagen (NTx/CR) were comparable.

Over an average follow-up period of 3.3 years, the overall rate of decline in hip BMD for women with diabetes throughout menopause was 10-fold greater (P = .003) than for women without diabetes. Women without diabetes, however, had a rate of spinal BMD loss that was significantly higher than for women with diabetes (P = .005).
The number of women with diabetes reporting a fracture over the follow-up period was 2-fold higher (4%) than those without diabetes (2%).

“The mechanisms behind this phenomenon in postmenopausal women is unclear, but factors such as insulin fluctuations are considered main reasons. The study provides evidence that despite higher baseline BMD at all bone sites, rate of total hip bone loss is greater in women with diabetes but [spine-bone loss is lower] as they transition menopause," the researchers conclude. .

Ann V. Schwartz, PhD, associate professor of epidemiology and biostatistics at the University of California at San Francisco, said.” I thought it was most interesting that there was more rapid bone loss at the hip for the women with diabetes, but there was an opposite finding at the spine"

Previous reports have also shown more rapid bone loss at the hip, in spite of higher baseline BMD, among women with type 2 diabetes, with the suggestion being that type 2 diabetes has a positive effect on trabecular bone but possibly a negative effect on cortical bone, Dr. Schwartz explained. The findings underscore the need to consider a heightened fracture risk among women with diabetes, she added.

Source : American Society for Bone and Mineral Research (ASBMR) 31st Annual Meeting: Abstract 1205. Presented September 13, 2009.