January 30, 2018
Osteoporosis is the most common of the metabolic bone diseases. The normal balance between bone resorption and bone formation is upset with osteoporosis resulting in loss of bone mass and an increase in risk of fracture. Osteoporotic fractures as the result of critically low bone density are frequently referred to as fragility fractures, which are typically fractures caused by impacts that would not be strong enough to fracture a healthy bone - for example, a fall from a standing height. According to Dr. William T. Jones, M.D. of the Orthopaedic and Sports Medicine Center, more than half of the people in the United States over the age of 50 have low bone mass, which is frequently referred to as osteopenia, and critically low bone mass, or osteoporosis.
“It is really considered to be a silent epidemic. It is a silent epidemic as most people remain relatively asymptomatic until they sustain a fragility fracture or secondary joint destruction,” Dr. Jones said. “It does not get the attention of things like cardiovascular disease or cancer, but there are alarmingly high numbers of people that have it. Only 25% of women over the age of 60 have normal bone mineral density. So, it is a huge problem.”
Approximately 50% of women and 33% of men will sustain a fragility fracture during their lifetime. It is estimated that less than 25% of people with low bone density actually receive treatment.
Fragility fractures have significant implications. For example, only 50% of women after a fragility hip fracture are able to ambulate at their accustomed level, and the mortality rate is 20% in the first six months after the fracture. In addition, fragility fractures many times significantly impact the ability to maintain an independent life style.
The diagnosis of low bone mass has been standardized utilizing a special x-ray called a Dexa scan. The Dexa scan measures bone mineral density. A bone mineral density evaluation is typically performed at a certain age based on sex and for anyone with a fragility type fracture. Most bone mineral density scans are ordered and interpreted by primary care physicians. The scan allows for the objective measurement of bone weakness which in turn is used to establish treatment protocols and prognosis. Knowing the bone mineral density and other information allows for the calculation of a 10-year fracture risk which is called a FRAX score. For instance, if an individual’s 10-year fracture risk is greater than 30% for the hip or greater than 20% for the proximal humerus, wrist, or vertebral body, pharmacologic treatment is considered. There are many nuances of the FRAX score including serum vitamin D, fall risks potential of the individual, and biochemical markers of bone turnover.
Risk factors for osteopenia and osteoporosis include an older age; female; low BMI (body mass index); Caucasians; history of fragility fracture; strong family history of osteoporosis or fragility fractures; auto-immune disease such as rheumatoid arthritis, diabetes mellitus, malignancy, HIV and hepatitis C; and heavy smoking and alcohol consumption.
Treatment is based on many variables, however, as much information as possible should be obtained, particularly in those at risk for low bone mineral density. For instance, data demonstrates a 400% decrease in the 3-year risk of subsequent fracture with appropriate anti-osteoporotic treatment. Optimizing osteopenia/osteoporosis treatment to prevent subsequent fractures in the elderly is an important public health goal but often overlooked.
In addition to a bone mineral density, your primary care physician may perform a number of screening laboratory studies associated with bone mineral density such as TSH, CBC, testosterone, vitamin D levels, protein electrophoresis, and 24-hour urine calcium.
Baseline treatment for anyone with low bone mineral density includes vitamin D and calcium replacement in conjunction with life style modifications including smoking cessation, decrease in alcohol intake, weight bearing exercises, improved nutrition, and fall prevention measures.
Depending upon the situation, your primary care physician may consider pharmacologic treatment. Bisphosphonates are the most commonly used and include medications such as Fosamax, Actonel, Reclast, Boniva, and Didronel. Calcitonin is frequently used early on in the treatment of significant loss of bone mineral density.
Beyond initial pharmacologic treatment, other agents may be considered such as anabolic agent such as Forteo, which is similar to parathyroid hormone, or Prolia, which is the first biologic approved for the treatment of osteoporosis. All of the pharmacologic agents have associated risks and limitations which will need to be reviewed and discussed prior to initiating treatment.
In summary, osteopenia and osteoporosis are common and frequently underrecognized and undertreated. Please contact your primary care physician for diagnosis, prevention, and treatment.