Treatment of Osteoporosis

Osteoporosis is our most common metabolic bone disease. It has been defined as “a skeletal disorder characterized by compromised bone strength predisposing to an increased risk of fracture”. Fractures produce significant morbidity and mortality, as well as a tremendous economic burden for our health care system. Since osteoporosis is often clinically silent, it is imperative that we make a concerted effort to identify patients who are at risk for fracture. Studies have shown that effective screening of an at-risk population can result in a decreased incidence of fracture.

Osteoporosis is both a preventable and a treatable disease. Important advances have been made in the ability to prevent and treat fractures in the last decade, particularly in people with skeletal fragility. Any individual patient’s risk of a fracture is dependent upon a variety of factors. Of the various factors the most important one is the bone mineral density (BMD). BMD correlates highly with fracture risk and allows the clinician to determine the need for pharmacological interventions. Dual energy X-ray absorptiometry (DXA) has become the most commonly used method to measure BMD. A score called ‘T’ score is then calculated using BMD.

A patient diagnosed to have osteoporosis has to be treated if he satisfies the following criteria:

• T-score is less than:2.0
• T-score is less than:1.5 with a major risk factor
• Major risk factors
• Personal history of fracture
• Family history of fracture
• Current cigarette smoker
• Weight less than 127 pounds

The four major goals in the treatment of osteoporosis are

• To prevent fracture
• To stabilize bone mass or achieve increased bone mass
• To relieve symptoms of fractures and skeletal deformity
• To maximize physical function

The U.S. surgeon general has recommended a three-level pyramidal approach to treatment in order to achieve these goals:

• Lifestyle changes form the base of the prevention and management pyramid, including adequate calcium and vitamin D intake, physical activity, and fall prevention.
• The second level includes assessing and treating secondary causes.
• The third level includes pharmacological interventions to improve bone density and reduce the risk of fracture

The various medications that are used to treat osteoporosis are given below:

• Bisphosphonates - Their primary mechanism of action is inhibition of bone destruction activity and thereby slowing deterioration and allowing bone formation activity to slightly increase BMD. Alendronate (Fosamax®), risedronate (Actonel®), and ibandronate (Boniva®) are second- and third-generation bisphosphonates and are currently approved by the FDA. Bisphosphonate therapy should be considered first-line therapy for the treatment of osteoporosis, in conjunction with lifestyle modifications and appropriate doses of calcium plus vitamin D. Abdominal pain, dyspepsia, and nausea are some of the side effects of biphosphonates.
• Parathyroid Hormone Therapy - The recombinant human parathyroid hormone, teriparatide (Forteo®), is currently the only available agent in this class of medication. It is administered as a once-daily injection and is approved for use for up to 24 months. Pain, redness, itching and bone tumor are some of the side effects of this medication.

Estrogen Therapy - Estrogen is an essential hormone that is important throughout life for bone development in both men and women. The current recommendations are that estrogens be used at the lowest doses for the shortest period of time needed to reach treatment goals. Estrogens can be administered orally, intravaginally, transdermally, parenterally, and by topical application of a gel or emulsion to the skin.

Selective Estrogen Receptor Modulators (SERMs) - The biological actions of SERMs are principally mediated via binding to estrogen receptors. Thus they act like estrogen. Raloxifene and tamoxifen are the medications which belong to this group. These medications can cause clotting in the blood vessels.

Calcitonin (Salmon) Therapy - Calcitonin (Miacalcin®) is a hormone secreted by the thyroid’s parafollicular gland in mammals. In the treatment of osteoporosis, calcitonin derived from a salmon’s gland is utilized, due to its greater potency and prolonged duration of action when compared to mammalian calcitonin. Most recently, a daily nasal spray formulation was added as a dose delivery system. The medication is generally well tolerated without significant reporting of adverse events.

Calcium and Vitamin D -Calcium is a mineral that accounts for 1% to 2% of the adult human body weight and plays a vital role in the development and maintenance of a healthy skeleton. Vitamin D (calciferol) is vital for bone health because it assists in the absorption and utilization of calcium. The major source of vitamin D is sunlight, which the human body absorbs by exposure to sunlight through the conversion of precursors in the skin to active vitamin D. Consumption of adequate levels of calcium and vitamin D throughout life and appropriate physical activity are essential to bone health