Type 1 Diabetes Tied to Thinner Bones

Study: Women With Type 1 Diabetes May Need Early Bone Density Test

From an article by Miranda Hitti WebMD Medical News which was reviewed by Louise Chang MD- January 27, 2006

Women with type 1 diabetes may want to consider getting their bone density checked before menopause, researchers report.

The scientists studied bone density in women with and without type 1 diabetes.

Their finding:

Women with type 1 diabetes tended to have thinner bone and more bone fractures.

Thinner bone is at higher risk to break and can be a sign of developing osteoporosis, in which bone density dips dangerously low. Think of the difference between a thin, brittle twig and a thick, firm tree branch -- denser is better to avoid a sudden snap.

The University of Pittsburgh's Elsa Strotmeyer, PhD, and colleagues conducted the study, which appears in Diabetes Care.

Study Details

Osteoporosis usually strikes later in life. In women, it's typically seen after menopause. Men can also develop osteoporosis, but Strotmeyer's study only included women.

Participants were 67 women with type 1 diabetes and 237 women without diabetes. The women were 33-55 years old and had not gone through menopause. The researchers checked the women's height, weight, and bone density.

The women also completed surveys about health habits that can affect bones e.g.

• weight-bearing exercise
     or
• smoking
• heavy drinking
• use of certain medications
• skimping on calcium and vitamin D

Weaker Bones With Type 1 Diabetes

Even after adjusting for those factors, women with type 1 diabetes had lower bone density than those without diabetes.

In addition, a third of women with type 1 diabetes reported having a bone fracture after age 20, compared with less than a quarter of those without diabetes.

It's not known if the results apply to men or to people with type 2 diabetes, since they weren't included in the study.

Most people with diabetes have type 2 diabetes, which usually starts later in life than type 1 diabetes. For instance, in Strotmeyer's study, women with type 1 diabetes had been diagnosed at age 10, on average, and had had type 1 diabetes for more than 30 years.

Bone Density Tests

To measure the women's bone density, the researchers used a DEXA (dual-energy X-ray absorptiometry) machine. The machine checked the women's overall bone density as well as the density of their hips, neck, and spine.

Bone density peaks in the 30s.

After that, bones gradually lose density over time.

Bone density tests usually aren't done until after menopause, since that's when bone density starts to decline at a greater rate.

If the study's findings are correct, type 1 diabetes could join the list of other osteoporosis risk factors, which include:

• Being postmenopausal
• Having a family history of osteoporosis
• Being of European or Asian ancestry
• Having a medical condition such as hyperthyroidism that makes it hard to absorb enough calcium
• Having a small frame
• Being a smoker

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Treating osteoporosis can mean taking prescription drugs, boosting intake of calcium, vitamin D, and other bone-friendly nutrients, and getting weight-bearing exercise.

Walking, jogging, hiking, dancing, and lifting weights are some examples of weight-bearing exercise.

Biking and swimming aren't in that group, since the bike or water carries your weight.

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SOURCES: Strotmeyer, E. Diabetes Care, February 2006; vol 29: pp 306-311. WebMD Medical Reference from Healthwise: "Should I have a DEXA test to diagnose osteoporosis?" News release, American Diabetes Association