Osteoporosis is a disease of bone, more common in the elderly, especially women wherein the bones become very weak and brittle and prone to break (fracture) easily.

Normal healthy bone viewed under a microscope appears similar to a honeycomb. In osteoporosis, which literally means “porous bone”, the gaps and spaces in the honeycomb are much larger when compared to normal healthy bone.

Bone is a dynamically active tissue and is continuously being remodelled by a process of breakdown and rebuilding. As one ages, and due to certain diseases, this capacity for renewal becomes lesser relative to breakdown, resulting in fragile porous bone or osteoporosis.

Differences in bone breakdown and rebuilding with age
? Early childhood – Rapid growth of new bone as long bones increase in size and the child grows
? Adolescence to mid-20s – Rapid bone growth occurs to build bone strength and density
? Mid-20s to early 40s – Fine balance between bone breakdown and renewal
? After 40 years – Bone becomes thinner and less dense because bone breakdown is faster that the rate of renewal

Thus, as one gets older, the chances of developing osteoporosis increases and it is important to address other risk factors.

Risk factors for development of osteoporosis – Unmodifiable
• Increasing age
• Female sex
• Asian or Caucasian ancestry
• Small build – persons with smaller frame have less bone mass to draw upon with age
• Family history of osteoporosis in a parent or sibling

The above mentioned factors are unmodifiable risks. There are also other modifiable risk factors that could be addressed or corrected to decrease the chances of developing osteoporosis. These include

Hormonal disorders
• Low levels of sex hormones – Oestrogen deficiency in women after menopause and low testosterone in elderly men. Anti-hormonal treatments in breast and prostate cancers also increase risk
• Increased levels of thyroid hormone – hyperactive thyroid, thyroid hormone replacement for hypothyroidism
• Hyperactive parathyroid or adrenal glands

Reduced dietary intake/absorption
• Diet low in calcium
• Surgical removal of part of stomach or small intestine – reduces surface area available for absorption of nutrients including calcium

Medication use – longterm steroids, antiseizure medications, medications used to prevent transplant rejection, proton pump inhibitors, heparin, methotrexate, cancer drugs

Disease states
• Diseases of stomach or intestine – reduced absorption of calcium
• Kidney or liver disease – disordered calcium and vitamin D metabolism

Lifestyle factors – Smoking, excessive alcohol consumption, sedentary lifestyle and lack of exercise

Signs and Symptoms of Osteoporosis
It is important to bear in mind that in many cases, osteoporosis develops silently and may be present without the person demonstrating any obvious clinical features. Some of the signs and symptoms associated with osteoporosis include

• Bone pain – hip pain, back pain due to fractured bone or vertebra
• Stooped posture – due to osteoporosis of spine
• Decrease in height
• Easy fracturing of bones with minor trauma

How is Osteoporosis Diagnosed?
There are no specific signs or features that are readily evident and it may remain undiagnosed for years.

If there is a suspicion that one may have osteoporosis or the presence of any of the risk factors such as longterm steroid intake, unexplained fracture, family history, early menopause before 45 years in a woman, one may be advised to undergo a DEXA (dual energy x-ray absorptiometry) scan test that measures bone density and determines fracture risk.

The DEXA Scan Test
The DEXA scan is a painless procedure that x-rays the bones of the body. There are no special preparations necessary before the procedure.

The test will be performed by a radiographer and takes around 15-20 minutes. Typically the hip bone and the spine will be x-rayed but if that is not possible, then the forearm bone may be x-rayed.

Results of the DEXA Scan
The various results possible are
Normal – Risk of low impact fracture remains low
Osteopenia – Risk of low impact fracture still low but bone slightly weaker. No specific treatment may be required at this stage. You will be advised to reduce the modifiable risk factors that may be present and to reduce the risk of falls
Osteoporosis – Risk of low impact fractures is high. Specific treatment may be required

Treatments for Osteoporosis
If the DEXA scan results suggest a higher risk of fractures, any of the following medications may be needed to reduce risk of fractures and increase bone density
Bisphosphonates
This group of drugs is most commonly prescribed in both men and women at a higher risk of fractures. They slow down bone loss and reduce fracture risk. Drugs include Alendronate, Zoledronic acid, Risedronate, and Ibandronate

Hormone replacement therapy
Estrogen therapy initiated immediately after menopause may improve bone health but is not recommended as first line because of the increased risk of blood clots and some cancers.

Raloxifene mimics the effects of estrogen without an increased risk of cancer but is associated with an increased risk of blood clots

Other medications
Teriparatide – It is similar to parathyroid hormone and given to patients who are unable to tolerate other treatments or have fractures despite other medications

Calcitonin
This is a hormone that is normally produced in our body. It is given as injections for short-term to treat painful vertebral fractures or longterm as intranasal spray to treat osteoporosis

Denosumab
It may be advised in women who find it difficult to take bisphosphonates. It is given as an injection under the skin only twice a year. It increases bone density and strength and reduces fracture risk.

Ways to reduce risk or prevent osteoporosis
• Quit smoking.
• Limit intake or stay off alcohol.
• Maintain a healthy weight and improve your muscle strength and bone density. Weight bearing exercises (running and walking) are more beneficial in reducing risk of osteoporosis but any form of exercise is good
• Include calcium and vitamin D in your diet; if you are deficient take calcium and vitamin D supplements
• Reduce risk of falls by making suitable changes to the furniture at home, using a walking stick etc
• Discuss with your doctor about treatments that help to decrease bone loss