Risk Factors

Osteoporosis and diabetes

Osteoporosis is a disease that causes weak bones as a result of which a person is at an increased risk of fractures. It is usually observed that adult women with type 1 diabetes have relatively decreased bone mass, increased fracture risk, and delayed fracture healing compared with healthy women without diabetes. However, patients with type 2 diabetes usually do not have a decreased bone mass and, in fact, may be relatively protected from osteoporosis.

Symptoms

The symptom is a broken bone, although other noticeable signs can include height loss and curvature of the spine that occur slowly over time. Early onset of diabetes, in particular, is associated with reduced bone density, and patients with type 1 diabetes show evidence of low bone mass following adolescence. This could be the reason why there is a higher incidence of hip fracture reported for postmenopausal women with type 1 diabetes.

Decreased calcification or density of bone is called osteopenia, the link of which with diabetes appears to be associated with a decreased bone turnover. This is reflected in a decrease in serum markers of bone formation, such as osteocalcin. Bone loss (resorption) and formation are usually tightly coupled, although it has not been well studied in patients with diabetes.

Risk and Diagnosis

It is important for people who may be at risk for osteoporosis to be screened. Bone mineral density testing provides an easy and accurate measure of risk for osteoporosis.

Common tests include:

• Dual-energy X-ray Absorptiometry (DXA),
• Quantitative Computed Tomography (QCT),
• Peripheral DXA or QCT, and
• Peripheral Heel Ultrasound

In contrast to findings in type 1 diabetes, patients with type 2 diabetes do not have low bone mass and may be relatively protected from osteoporosis. However, studies in type 2 diabetes indicate that, while bone turnover is suppressed in patients in poor glycemic control, bone metabolism returns to normal with normalization of glycemia.

The following factors put a person at a higher risk of osteoporosis. While some of them are avoidable, some are not:

• Female or of advanced age
• Having a hormone deficiency (testosterone in men or estrogen in women)
• A woman who had early menopause (before age 45)
• Use of certain medications, such as steroids or anti-seizure drugs, or too many supplements for thyroid or vitamin A
• Intake of a diet low in calcium
• Being inactive or immobile
• Smoking or excessive use of alcohol
• Having parents or siblings with osteoporosis
• Having certain medical conditions, including diabetes, cystic fibrosis, malabsorption syndromes, some genetic diseases, kidney disease, thyroid disease, bulimia, or anorexia;
• Having a thin body and small bone frame
• Being white or Asian (although members of other races can also be affected).

Bone loss in diabetics

The difference in bone loss between the two forms of diabetes is often attributed to the degree of adiposity. Increased body weight has been associated with an increased bone mass in both normal and diabetic individuals, and may account for the relative protection seen in patients with type 2 disease. Apart from the mechanical effects of increased weight bearing, many women who are obese and relatively insulin-resistant have increased levels of androgens, which may contribute to bone maintenance.

According to experts, hyperinsulinemia may be partially responsible for the association of both diabetes and obesity with a higher body mass index in women. Besides, patients of type 2 diabetes are at a higher risk of fracture despite having normal bone mass. This may be because other factors, such as neuropathy and impaired vision, contribute to the increased fracture risk.

Prevention

Usually the bones grow and achieve their peak bone mass in youth and up to age 35. it is during this time, that one can make the bones as strong as possible by eating a healthful diet and exercising regularly.

Persons above the age of 35 can help prevent bone loss by getting enough calcium and vitamin D, performing weight-bearing exercises, and maintaining an overall healthy lifestyle. Consultation with a personal health care provider about the right amount of calcium and vitamin supplements is required for this.

Other ways to prevent risk of bone fractures are:

• Preventing falls
• Wearing sturdy shoes
• Making sure about the safety of daily environment
• Wearing hip pads in case of bone loss that has already begun

Treatment

Type 1 diabetes does appear to be a significant risk factor for osteoporosis. The currently recommendations are that patients with type 1 diabetes be monitored more carefully than persons without diabetes or those with type 2 disease. Besides, type 1 diabetics need to be encouraged to consume a diet high in both calcium (at least 1200 mg/day) and vitamin D (400-600 IU/day). Further, it appears that intensive insulin therapy and a stable body weight in patients with type 1 diabetes is important in preventing bone loss.

Patients with diabetes and osteopenia or osteoporosis have successfully been treated with bisphosphonates, with similar bone density results as patients without diabetes.

For patients with type 2 diabetes who are in good metabolic control, prevention and treatment of osteoporosis can be approached in a manner similar to patients without diabetes.

Different drugs are available for treating osteoporosis. A personal health care provider can help decide the right one for an individual. Commonly used drugs include:

• Bisphosphonates, such as Actonel (risedronate) or Fosamax (alendronate)
• Miacalcin (a calcitonin nasal spray)
• Evista (raloxifene)

Diabetics who are at a risk for developing osteoporosis, need to talk to their health care provider about getting screened and, if necessary, developing a treatment plan.

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