July 7, 2006

Diabetic women need fracture prevention strategy

By Megan Rauscher

NEW YORK (Reuters Health) - After 22 years of following
women with type 1 or 2 diabetes, researchers detected a
statistically significant increased risk of hip fracture,
highlighting the need for prevention efforts in this

"Increased risk of fracture has not traditionally been
considered a consequence of diabetes mellitus," Dr. Mohsen
Janghorbani from Isfahan University of Medical Sciences in Iran
noted in an email to Reuters Health.

"However, this study, as well as several other
observational studies, has demonstrated that individuals with
type 1 and type 2 diabetes are at increased risk of hip
fracture and fall, despite higher weight than nondiabetic
control individuals," the researcher added.

The findings are based on data from 109,983 women aged 34
to 59 years in 1980 who were followed through 2002. As
participants in the Nurses' Health Study, the women were asked
about their history and treatment of diabetes and other
potential risk factors for hip fracture.

During the study period, 1,398 women (1.2 percent)
fractured a hip, Janghorbani and colleagues at Harvard
University, Boston, note in the July issue of Diabetes Care.

Compared with nondiabetic women, after factoring in the
effects of age, the risk of fracture was seven times higher in
women with type 1 diabetes and almost twice as high in those
with type 2 diabetes, the researchers report.

After further adjusting the data for the effects of weight,
smoking, physical activity, menopausal status, postmenopausal
hormone use, and daily intake of calcium, vitamin D, and
protein, the risk of hip fracture was more than six times
higher women with type 1 diabetes and more that two-times
higher in women with type 2 diabetes.

The mechanisms involved in these negative effects on
fracture risk in diabetes are not entirely clear, the
investigators note. The risk of hip fracture increased with
longer duration of type 2 diabetes; having type 2 diabetes for
12 or more years was associated with a three-times higher risk
of hip fracture, compared with no diabetes.

The risk of hip fracture also increased with insulin
treatment. This may indicate a more severe disease process, the
team notes, rather than being a direct contributor to hip
fracture. On the other hand, insulin may exert negative effects
on the bones. The role of insulin in fracture risk is
uncertain, they add, and requires more study.

Overall, "the results of this study highlight the need for
fracture and fall prevention strategies in patients with
diabetes," Janghorbani concluded.

SOURCE: Diabetes Care, July 2006.