How to Predict Bone Fracture Risk with Osteoporosis or Osteopenia

Both men and women can develop osteopenia and osteoporosis. These terms describe a condition in which the bones become more fragile due to a decrease in the bone mineral density. The decreased density of the bone puts individuals at a significantly increased risk of bone fractures.

Postmenopausal women with osteoporosis and men that are older than 50 years of age with osteoporosis are often treated with medicines in an attempt to decrease fracture risk and minimize future bone density loss. Osteopenia is the precursor to osteoporosis. The detection of osteopenia on a bone scan suggests that therapeutic lifestyle changes are required in order to thwart the progression to osteoporosis.

The ability to predict the 10-year risk of fracture in individuals is very useful in guiding treatment. For example, individuals with osteopenia require lifestyle change. However, according the World Health Organization Fracture Assessment site, postmenopausal women and men over age 50 with osteopenia plus a greater than 3% 10-year probability of developing a hip fracture may require medications in addition to lifestyle adjustment.

Many risk factors have been identified that can contribute to bone fracture risk in men and women. Using these factors, a risk calculator has been developed. This risk calculator is known as the FRAX calculator and is available free for public use on the world wide web at http://www.sheffield.ac.uk/FRAX/ .

The developers of the FRAX calculator evaluated various characteristics of large populations through out the world and have developed specific calculators based on these populations. Thus it is important to choose the right calculator. For example, United States Caucasian versus United States Hispanic.

The factors that the fracture risk calculator utilizes include:

-Age: Between 40 and 90 years.

-Sex: Male or female

-Weight: Entered in kg.

-Height: Entered in cm.

-History of a previous spontaneous fracture in adult life, or a fracture from a trauma which would not have resulted in a fracture in a healthy individual.

-History of hip fracture in the patient's mother or father.

-Current smoking of tobacco.

-Glucocorticoids: Currently taking oral glucocorticoids (such as prednisone) or previous exposure to oral glucocorticoids for at least 3 months at a dose of at least 5mg per day of prednisolone.

-Rheumatoid arthritis: Only include for a confirmed diagnosis of rheumatoid arthritis. Patients may confuse osteoarthritis (which is actually protective) with rheumatoid arthritis.

-Secondary osteoporosis: This includes disorders strongly associated with osteoporosis such as type I (juvenile insulin dependent) diabetes, osteogenesis imperfecta in adults, hyperthyroidism that has gone untreated for a long period of time, hypogonadism in men or early menopause in women at less than 45 years of age, chronic malnutrition, and chronic liver disease.

-Alcohol: A risk if 3 or more units per day are consumed. One unit of alcohol is considered to be a glass of beer (285ml), a single measure of liquor (30ml), or a medium-sized glass of wine (120ml).
-Bone mineral density (BMD): The actual femoral neck BMD (in g/cm²) from a DEXA (or DXA) bone scan is used. In patients without a BMD test, the field is left blank.

Once all of the individual's risk factors are entered in to the calculator a specific 10 year probability of developing a bone fracture is determined. Individuals should then work with their physician in order to determine whether lifestyle interventions and/or medical treatment is necessary.

Reference:

FRAX - The WHO Fracture Risk Assessment Tool http://www.sheffield.ac.uk/FRAX/ .