Osteoporosis

The word osteoporosis means spongy (porous) bone. Bone is made up of minerals, mainly calcium salts, bound together by strong collagen fibres. Our bones have a thick, hard outer shell (called cortical or compact bone) which is easily seen on x-rays. Inside this, there’s a softer mesh of bone (trabecular bone) which has a honeycomb-like structure.

Bone is a living, active tissue that’s constantly renewing itself. Old bone tissue is broken down by cells called osteoclasts and is replaced by new bone material produced by cells called osteoblasts. The balance between the breakdown of old bone and the formation of new bone changes at different stages of our lives.

In childhood and adolescence, new bone is formed very quickly. This allows our bones to grow bigger and stronger (denser). Bone density reaches its peak by our mid to late-20s.

After this, new bone is produced at about the same rate as older bone is broken down. This means that the adult skeleton is completely renewed over a period of 7–10 years.

Eventually, from the age of about 40, bone starts to be broken down more quickly than it’s replaced, so our bones slowly begin to lose their density

How does a normal joint work?

A joint is where two bones meet. Most of our joints are designed to allow the bones to move in certain directions and within certain limits.

For example, the knee is the largest joint in the body and one of the most complicated. It must be strong enough to take our weight and lock into position, so we can stand upright.

It also has to act as a hinge, so we can walk, and needs to twist and turn when we run or play sports.

The end of each bone is covered with cartilage that has a very smooth, slippery surface. The cartilage allows the ends of the bones to move against each other, almost without rubbing.

If you have rheumatoid arthritis, your immune system can cause inflammation inside a joint or a number of joints. Inflammation is normally an important part of how your immune system works.

It allows the body to send extra fluid and blood to a part of the body under attack from an infection. For example, if you have a cut that gets infected, the skin around it can become swollen and a different colour.

However, in rheumatoid arthritis, this inflammation in the joint is unnecessary and causes problems.

When the inflammation goes down, the capsule around the synovium remains stretched and can’t hold the joint in its proper position. This can cause the joint to become unstable and move into unusual positions.

The main symptoms of rheumatoid arthritis are:

• Joint pain

• Joint swelling, warmth and redness

• Stiffness, especially first thing in the morning or after sitting still for a long time.

Other symptoms can include:

• Tiredness and lack of energy – this can be known as fatigue

• Not feeling hungry

• Weight loss

• A high temperature, or a fever

• Sweating

• Dry eyes – as a result of inflammation

• Chest pain – as a result of inflammation.

Rheumatoid arthritis can affect any joint in the body, although it is often felt in the small joints in the hands and feet first. Both sides of the body are usually affected at the same time, in the same way, but this doesn’t always happen.

A few people develop fleshy lumps called rheumatoid nodules, which form under the skin around affected joints. They can sometimes be painful, but are not usually.

The following can play a part in why someone has rheumatoid arthritis:

• Age: Rheumatoid arthritis affects adults of any age, although most people are diagnosed between the ages of 40 and 60. Around three-quarters of people with rheumatoid arthritis are of working age when they are first diagnosed.

• Sex: Rheumatoid arthritis is two to three times more common among women than men.

• Genetics: Rheumatoid arthritis develops because of a combination of genetic and environmental factors. If you have a genetic predisposition to rheumatoid arthritis, it means you have an increased likelihood of developing the condition based on your genetic makeup. It is unclear what the genetic link is, but it is thought that having a relative with the condition increases your chance of developing the condition.

• Weight: If you are overweight, you have a significantly greater chance of developing rheumatoid arthritis than if you are a healthy weight.

• Smoking: Rheumatoid arthritis develops through a combination of genetic and environmental factors. Cigarette smoking is classed as an environmental factor and significantly increases the risk of developing the condition. If you would like to stop smoking, visit the Smoke free website for advice.

• Diet: There is some evidence that if you eat a lot of red meat and don’t consume much vitamin C, you may have an increased risk of developing rheumatoid arthritis.

A diagnosis of rheumatoid arthritis is based on your symptoms, a physical examination and the results of x-rays, scans and blood tests.

Because rheumatoid arthritis can affect other parts of the body, it’s important to tell your doctor about all the symptoms you’ve had, even if they don’t seem to be related.

• Blood tests: Blood tests may be used to find changes in your blood that are produced by inflammation. They can also show if you’re anaemic, as anaemia is common in people with rheumatoid arthritis. Having anaemia means you have low levels of iron in your blood.

• X-rays and other tests: X-rays will show any damage caused to the joints by the inflammation that occurs in rheumatoid arthritis. Doctors also use equipment such as ultrasound scans to look for inflammation and early damage to joints.

When your diagnosis has been confirmed, don’t be afraid to ask your doctor questions or talk about any problems the condition causes you. The more your healthcare team know about how arthritis is affecting you, the more they can help.

There are a variety of treatments available for rheumatoid arthritis. The earlier that intensive treatment is started, the more likely it is to work.

There are three main ways to treat rheumatoid arthritis:

• Drugs

• Physical therapies

• Surgery

Drugs There are four main groups of drugs that are used to treat rheumatoid arthritis. These are:

• Painkillers: Painkillers can help to relieve the pain caused by rheumatoid arthritis, but should not be the only treatment used. There are many types and strengths of painkillers available – some can be bought over the counter from a pharmacy, while some are only available on prescription. For guidance, ask a healthcare professional in charge of your care.

• Non-steroidal anti-inflammatory drugs (NSAIDs): NSAIDs can be used to help control symptoms of pain, swelling or stiffness. They can be used in combination with painkillers. NSAIDs start working within a few hours, and the effects can be felt for up to a whole day.

• Disease-modifying anti-rheumatic drugs (DMARDs): You will probably be offered a combination of DMARDs as part of your rheumatoid arthritis treatment.

• Steroid treatment (also known as corticosteroids): Steroids are sometimes known by their full name: corticosteroids. Steroids help to reduce the pain, stiffness and inflammation caused by rheumatoid arthritis.

Many people with rheumatoid arthritis need to take more than one drug. This is because different drugs work in different ways.

Your drug treatments may be changed from time to time. This can depend on how bad your symptoms are, or because something relating to your condition has changed.

Drugs may be available under several different names. Each drug has an approved name – sometimes called a generic name.

Manufacturers often give their own brand or trade name to the drug as well. For example, Nurofen is a brand name for ibuprofen.

The approved name should always be on the pharmacist’s label, even if a brand name appears on the packaging. Check with your doctor, rheumatology nurse specialist or pharmacist if you’re not sure about anything.

Fracture Risk Assessment Tool (www.shef.ac.uk/frax)

Fracture Risk Assessment Tool (FRAX) estimates the 10-year probability of hip fracture and major osteoporotic fracture (hip, clinical spine, proximal humerus, or forearm), for untreated patients between age 40 to 90 years using clinical risk factors which include an individual's age, sex, weight, height, prior fracture, parental history of hip fracture, smoking, long-term use of glucocorticoids, rheumatoid arthritis and alcohol consumption.

The country-specific FRAX prediction algorithms are available for some countries but not for Malaysia. For Malaysians, we recommend the use of ethnic specific algorithms (e.g. Singapore Chinese or Hong Kong Chinese, Singapore Malay, Singapore Indian) until local data is available.

BMD is not necessary for calculation of fracture probability. However, it improves the prediction of fracture probability. If a BMD is available, only the femoral neck/total hip BMD is to be used. BMD input from non-hip sites has not been validated with FRAX and is therefore not recommended.

The treatment interventions in FRAX have been partly based on cost-effectiveness, for

which there is no Malaysian data. Notwithstanding that, we would propose using the National Osteoporosis Foundation Clinician’s Guide to Prevention and Treatment of Osteoporosis (2010),16 in that postmenopausal women and men over the age of 50 should be considered for treatment if they had a previous hip or vertebral fracture or a T-score < -2.5 on DXA after exclusion of secondary causes of osteoporosis. In patients with osteopenia, initiation of treatment is recommended with a fracture probability of more than 3% at 10 years for hip or 20% at 10 years for major osteoporosis related fracture.

If FRAX is not accessible, elderly individuals over 65 years of age with multiple risk factors who are at sufficiently high risk for osteoporosis, can be started on treatment.