Osteoporosis Support Group

Osteoporosis is a disease of bone in which bone mineral density (BMD) is reduced, bone microarchitecture is disrupted, and the amount and variety of non-collagenous proteins in bone is changed. Osteoporotic bones are more susceptible to fracture. Osteoporosis is defined by the World Health Organization (WHO) as either a bone mineral density 2.5 standard deviations below peak bone mass (20-year-old person standard) as measured by DEXA or any fragility fracture. While treatment modalities are becoming available, prevention is still the most important way to reduce fracture. Due to its hormonal component, more women, particularly after menopause, suffer from osteoporosis than men.

It is estimated that 1 in 3 women and 1 in 5 men over the age of 50 worldwide have osteoporosis. It is responsible for millions of fractures annually, mostly involving the lumbar vertebrae, hip, and wrist.

Patients at risk for osteoporosis (e.g. steroid use) are generally treated with vitamin D and calcium supplements. In renal disease, a different form of Vitamin D (1,25-dihydroxycholecalciferol or calcitriol which is the main biologically active form of vitamin D) is used, as the kidney cannot adequately generate calcitriol from calcidiol (25-hydroxycholecalciferol) which is the storage form of vitamin D.

In osteoporosis (or a very high risk), bisphosphonate drugs are prescribed. The most often prescribed bisphosphonates are presently sodium alendronate (Fosamax®) 10 mg a day or 70 mg once a week, risedronate (Actonel®) 5mg a day or 35mg once a week or and ibandronate (Boniva® once a month).

Other medicines prescribed for prevention of osteoporosis include raloxifene (Evista®), a selective estrogen receptor modulator (SERM). Estrogen replacement remains a good treatment for prevention of osteoporosis but, at this time, is not recommended unless there are other indications for its use as well.

Recently, teriparatide (Forteo®, recombinant parathyroid hormone 1-34) has been shown to be effective in osteoporosis. It is used mostly for patients who have already fractured, have particularly low BMD or several risk factors for fracture or cannot tolerate the oral bisphosphonates. It is given as a daily injection with the use of a pen-type injection device. Teriparatide is only licensed for treatment if bisphosphonates have failed or are contraindicated (however, this differs by country).

Oral Strontium ranelate (Protelos® - Servier) is the first in a new class of drugs called a Dual Action Bone Agents (DABA's), and has proven efficacy in the prevention of vertebral and non-vertebral fractures (including hip fracture). Strontium Ranelate works by stimulating the proliferation of osteoblast (bone building) cells, and inhibiting the proliferation of osteoclast (bone absorbing) cells. This means that strontium Ranelate increases BMD by forming new bone, rather than just preserving existing bone. In comparison to bisphosphonates which only act on one aspect of bone remodeling, strontium ranelate also preserves bone turnover, allowing the microarchitecture of the bone to be continuously repaired as it would in healthy bone. Strontium ranelate is taken as a 2g oral suspension daily, and is licenced for the treatment of osteoporosis to prevent vertebral and hip fracture (this may differ by country). Strontium ranelate has show significant efficacy at reducing both vertebral, and non-vertebral fractures in patients over the age of 80, who are the most at risk where osteoporosis is concerned. This is unique to strontium ranelate as bisphosphonates can only show efficacy in vertebral fracture reduction, not non-vertabral. Strontium ranelate has side effect benefits over the bisphosphonates, as it does not cause any form of upper GI side effect, which is the most common cause for medication withdrawal in osteoporosis.

Changes to lifestyle factors and diet are also recommended; the "at-risk" patient should include 1500mg of calcium daily either via dietary means (for instance, an 8 oz glass of milk contains approximately 300 mg of calcium) or via supplementation. The body will absorb only about 500 mg of calcium at one time and so intake should be spread throughout the day. However, the benefit of supplementation of calcium alone remains, to a degree, controversial since several nations with high calcium intakes through milk-products (e.g. the USA, Sweden) have some of the highest rates of osteoporosis worldwide. A few studies even suggested an adverse effect of calcium excess on bone density and blamed the milk industry for misleading customers. Some nutrionists assert that excess consumption of dairy products causes acification, which leaches calcium from the system, and argue that vegetables and nuts are a better source of calcium and that in fact milk products should be avoided. In any case, thirty minutes of weight-bearing exercise such as walking or jogging, three times a week, has been shown to increase bone mineral density, and reduce the risk of falls by strengthening the major muscle groups in the legs and back.

In a recent study that examined the relationship between calcium supplementation and clinical fracture risk in an elderly population, there was a significant decrease in fracture risk in patients that received calcium supplements versus those that received placebo. However, this benefit only applied to patients who were compliant to their treatment regimen.

Increasing vitamin D intake has been shown to reduce fractures up to twenty-five percent in older people, according to recent studies.

There is some evidence to suggest bone density benefits from taking the following supplements (in addition to calcium and vitamin D): boron, magnesium, zinc, copper, manganese, silicon, strontium, folic acid, and vitamins B6, C, and K.