What is Osteoporosis?

The word ‘osteoporosis’ literally means ‘porous bone’. It is a condition where a person gradually loses bone material so that his or her bones become gradually more fragile. As a result, they are more likely to break.

What Causes Osteoporosis?

Our bones grow during childhood and adolescence and reach a peak around the age of 30 (peak bone mass). Following that, the bones, although still remaining strong, gradually begin to lose their density and this loss continues as we get older.

The reason why we lose bone as we age is because our bones are constantly undergoing a remodeling process. Bone is removed from areas of micro-trauma (bone resorption) and replaced with new bone (bone formation). As we age, the amount of bone formed is less than the bone resorbed, hence a gradual decline after peak bone mass.

The bone loss speeds up in women after the menopause especially in the first 5 years. This is because the ovaries stop producing the female sex hormone, oestrogen – and oestrogen is one of the substances that helps reduce bone resorption and thus maintain bone density. Men suffer less from osteoporosis because their bones are stronger in the first place (more peak bone mass) and they do no go through the menopause.

The Effects of Osteoporosis

Osteoporosis may not lead to any symptoms, or often, the first indication that you may have osteoporosis is a broken (fractured) hip, wrist or spine after a minor fall. If bones are healthy, they should not break (fracture) as a result of a simple bump or fall.
If the bones in the spine become weak, they may crush making you shorter. If several are squashed, the spine will start to curve.
This may cause no symptoms or be associated with pain in the spine. If the spine becomes very curved, you may have breathing difficulties because of loss of space under the ribs. Following a hip fracture, 50% of people can no longer live independently and 20% die within the first 12 months. The pain from the wrist and spine fractures can reduce independence and quality of life. Also, there is the associated financial cost of treating the fracture. In Malaysia, it is estimated that over 1 million women are at risk from osteoporosis.

Are You at Risk?

All of us are at risk from osteoporosis as we get older, but there are some people who are more at risk than
others. These are some of the factors which can make a difference:

Oestrogen deficiency: Women who have had an early menopause (before the age of 45), or a hysterectomy (removal of the womb) where one or both ovaries have been removed are at risk.

Lack of exercise: Exercise keeps the bones strong – both as they are developing and throughout adulthood.
So, anyone who does not exercise, or has an illness which makes it difficult for them to move about, will be
more likely to develop osteoporosis.

Poor diet: A diet that does not include enough calcium can encourage osteoporosis (see next section).

Heavy smoking: Tobacco lowers oestrogen levels in women.

Heavy drinking (alcohol): A high alcohol intake reduces the ability of the body’s cells to make bone.

Steroids (prednisolone): If someone takes prednisolone over a long period of time, they can become
osteoporotic.

Family history: Osteoporosis can run in families. This is probably because there is an inherited factor that
affects the development of bones.

Previous fractures: People who have had a low trauma fracture are at greater risk of having another.

Can You Prevent Osteoporosis?

These are several things that we can do to keep our bones strong and healthy: Prevention concerns everyone. If you are under 30, it is important to build up strong bones; if you are older than 30, your objective is to keep bone loss to a minimum.

Table 1: Suggested Daily Calcium Intake

Adapted from South East Asia RDA Harmonisation (ILSI/FAO) 2002 & FAO/WHO (2002).
Human vitamin and mineral requirements. Report of a joint FAO/WHO expert
consultation, Bangkok, Thailand.

1) Healthy Diet: As our bones contain 99% of our body’s calcium stores, our diet should contain adequate amounts of calcium. Table 1 shows the recommended amounts of calcium you should try to take every day depending on age and Table 2 shows the calcium content of some common food.
In addition, vitamin D is required to absorb calcium. People with low levels of vitamin D have lower bone density.

The recommended daily vitamin D doses are as follows:
Children up to 18 years: 600 IU
Adult men & women 19 – 70 years: 600 IU
Adults over 70 years: 800 IU

2) Exercise: Weight bearing exercise, such as walking makes bones stronger and also improves balance, co-ordination and flexibility, helping to prevent falls. Three sessions of brisk exercise a week is recommended, but for those people that have not exercised for a long time, please see your doctor before starting, and start slowly.

3) Life-style: avoid smoking and drinking too much alcohol.

4) Hormone replacement therapy (HRT): HRT helps maintain bone density in post menopausal women and reduce the risk of hip fractures. However, you need to discuss with your doctor as all treatments have their risks and benefits, and HRT is not suitable for everyone. At present, HRT is not recommended as first – line treatment for the prevention of osteoporosis.

5) Raloxifene: Is a selective estrogen receptor modulator (SERM) which provides the beneficial effects of oestrogen without their potential disadvantages. It can be used for the prevention of osteoporosis in post menopausal women.

6) Alendronate: In low doses, this drug can be used to prevent osteoporosis.

Table 2: Calcium Content of Common Foods

How can Osteoporosis be Detected?

There are no obvious physical signs of osteoporosis. Very often, the first indication that someone has a problem is when he/she breaks a bone (fracture) following a minor accident.

If a doctor suspects osteoporosis, he/she can order a scan to measure the strength or density of the bones. The scan involves lying down on a couch, fully clothed, for 15 minutes, while your bones are x-rayed. The dose of x-rays received is tiny, approximately 1% of that received during a chest x-ray. The technique is called dual-energy x-ray absorptiometry (DXA) and is available at many hospitals in the major towns in Malaysia. Other techniques for measuring bone density, such as ultrasound may not give an accurate assessment of future fracture risk and the need for treatment.

Can Osteoporosis be Treated?

Apart from the preventative measures already described, there are other treatments available if you are suffering from osteoporosis. Some of these treatments can slow down the rate of bone loss and/ or reduce the risk of future fractures.

1) Pain Relief: Following a fracture, you may be in considerable pain. This may be relieved by pain killers, physiotherapy/hydrotherapy and/or calcitonin injections in the short term. At home, local heat or ice packs may be helpful.

2) Calcium and Vitamin D: As part of the treatment for osteoporosis, you should get adequate calcium and vitamin D, as suggested in the prevention section.

3) Raloxifene: Can reduce bone loss and prevent vertebral fractures.

4) Bisphosphonates: Are a class of drugs for osteoporosis which inhibit bone resorption. They all slow down
bone loss and prevent fractures. There are many ways to take bisphosphonates:
(a) Orally once a week – Alendronate, risedronate
(b) Orally once a week – Ibandronate
(c) Intravenous (through an injection into a vein) once a year - Zoledronate

5) Strontium: Strontium works by stimulating bone formation and reducing bone resorption. It improves bone density and reduces fractures. It is taken daily.

6) Parathyroid hormone (PTH): Is a hormone naturally produced by our bodies. Given daily by subcutaneous injection, it stimulates bone formation leading to increased bone density and reduction in fractures.

We hope that you have found this booklet helpful. If you would like to know more about osteoporosis, please talk to your doctor.