A human bone is a living tissue that continually keeps changing. Right from the time when a child is born until young adulthood, human bones develop and gain strength. Bones are most dense when we are in our early 20s.
As we start aging, we undergo a process called remodeling where the bone cells begin dissolving bone matrix (called resorption), and new cells start depositing osteoid. In certain people, the pace of bone loss is quicker than the development of new bone.
The net result is bone loss and weakened, brittle bones. This disease is called osteoporosis. Osteoporosis mostly affects older women.
DiagnosisMany fear that brittle bones mean increased propensity to have a fracture. But it’s not true. Having osteoporosis does not necessarily cause a fracture.
Pharmacological advancements have resulted in the development of new drugs which reduces the pace of bone loss and helps in rebuilding bone strength.
A bone density test conducted by your doctor will help in determining if you have osteoporosis. A bone density of the bones present in the spine and hip is tested using DEXA (dual-energy x-ray absorptiometry) scan.
The result known as a T-score is then compared with the bone density of a healthy woman (aged around 30).
You will be recommended medications if:
- T-score is 2.5 or less
- There is a history of vertebral or hip fracture caused by a fall from a standing position
- T-score is 1.0 and –2.5 (a condition called osteopenia) and having a higher risk of osteoporotic fracture in the next ten years
Treatment OptionsTo slow the pace of bone loss, doctors have focused on bisphosphonates – a class of drugs. There are several types of medications available in this class.
- Pills – Fosamax (alendronate), Boniva (ibandronate), or Atelvia, Actonel (risedronate) - taken on a daily, weekly, or a monthly basis
- Boniva (ibandronate) injections – given once a quarter
- Intravenous infusion of Reclast (zoledronic acid) – taken yearly
Your doctor, besides determining the T-score, also determines the primary area of your bone loss. Based on this, medication will be given.
Alendronate, ibandronate, and risedronate are very useful for spinal fractures. Women having a history of nonspinal or hip fracture are given risedronate or alendronate.
If oral bisphosphonate causes gastrointestinal problems or inability to sit or stand straight for an hour, doctors will switch you to either injection or infusion, which also works well.
There are associated risks with the use of bisphosphonate drugs (femoral fractures and osteonecrosis are typical).
These, however, are more common in patients taking intravenous bisphosphonates for the treatment of cancer which has spread to bone or women taking high-dose bisphosphonates for a long time.
To address the long-term use, doctors tend to restrict medicines to five years. Despite stopping the medication, bone-protective benefits do continue.
Other Available Drug OptionsFor women (postmenopausal) who either have been on a bisphosphonate for five years or have not started them, there are other drug options.
Evista (raloxifene)A selective estrogen receptor modulator (SERM), known for its use in breast cancer treatment, Evista is also used in treating osteoporosis.
It produces estrogen-like effects by binding estrogen receptors present in the body. For people with spinal osteoporosis, this drug helps in reducing the risk of fractures.
The significant side effects associated with Evista are muscle pain, hot flashes and increased risk of deep-vein thrombosis.
Forteo (teriparatide)A synthetic parathyroid hormone drug, Forteo, increases bone strength and density. The use of Forteo decreases the risk of fractures to a great extent.
Treatment with it is limited to two years, as there are not enough studies that can vouch for the success after that. You might be switched to a bisphosphonate after two years for maintaining bone density. A woman on Forteo needs a daily injection.
Prolia (denosumab)Given twice-yearly, Prolia prevents the formation of osteoclast cells. This drug might be an ideal option if there is intolerance to bisphosphonates.
Fortical, Miacalcin (calcitonin)The oldest class of drug, present since the 1980s, this is a hormone which binds itself with osteoclasts preventing bone loss.
Taken either as an injection or nasal spray, this class of drugs has been known to reduce spinal fractures. However, its success against other fractures is still doubtful.
Several other drugs are also in the play like Evenity (romosozumab), a new monoclonal antibody that was approved in 2019 by the US FDA for the treatment of osteoporosis.
Scientists are also working on drugs that are aimed at blocking sclerostin, a protein inhibiting bone formation.