Understanding bones and osteoporosis
Bone is made of collagen fibres (tough, elastic fibres) and minerals (gritty, hard material). It is a living tissue and contains cells that make, mould and resorb (take back up) bone. Initially, as you grow, bone formation exceeds bone resorption. But, as you get older, this reverses and, after about the age of 45, you start to lose a certain amount of bone material. Your bones become less dense and less strong. The amount of bone loss can vary. If you have a lot of bone loss, then you have osteoporosis. If you have osteoporosis, your bones can break more easily than normal, especially if you have an injury such as a fall. If you have a milder degree of bone loss, this is known as osteopenia.
How common is osteoporosis?
In the UK more than two million women are thought to have osteoporosis. Women lose bone material more rapidly than men, especially after the menopause when their levels of oestrogen fall. Oestrogen is a hormone and helps to protect against bone loss. At the age of 50, about 2 in 100 women have osteoporosis. This rises to 1 in 4 women at the age of 80. But, osteoporosis can also affect men. Over a third of women and one in five men in the UK have one or more bone fractures because of osteoporosis in their lifetime.
Who is at risk of osteoporosis?
All men and women have some risk of developing osteoporosis as they become older, particularly over the age of 60. As mentioned above, women are more at risk than men. The following situations may also lead to excessive bone loss and so increase your risk of developing osteoporosis. If you:
- Are a woman and you had your menopause before the age of 45.
- Have already had a bone fracture after a minor fall or bump.
- Have a strong family history of osteoporosis. (That is, a mother, father, sister or brother affected.)
- Have a body mass index (BMI) of 19 or less. (That is, you are very underweight.) For example, if you have anorexia nervosa. In this situation your levels of oestrogen are often low for long periods of time and, combined with a poor diet, can affect bones.
- Are a woman and your periods stop for six months to a year or more before the time of your menopause. This can happen for various reasons. For example, over-exercising or over-dieting.
- Have taken, or are taking, a steroid medicine (such as prednisolone) for three months or more. A side-effect of steroids is to cause bone loss. For example, long-term courses of steroids are sometimes needed to control arthritis or asthma.
- Are a smoker.
- Have an alcohol intake of more than four units per day. (See separate leaflet called ‘Recommended Safe Limits of Alcohol’ for details of what a unit of alcohol is.)
- Lack calcium and/or vitamin D (due to a poor diet and/or little exposure to sunlight).
- Have never taken regular exercise, or have led a sedentary lifestyle (particularly during your teenage years).
- Have, or had, certain medical conditions. For example, an overactive thyroid, Cushing’s syndrome, Crohn’s disease, chronic kidney failure, rheumatoid arthritis, chronic liver disease, type 1 diabetes or any condition that causes poor mobility.
What are the symptoms and problems of osteoporosis?
Osteoporosis usually develops slowly over several years without any symptoms. However, after a certain amount of bone loss, the following may occur.
A bone fracture after a minor injury such as a fall
This is often the first sign or indication that you have osteoporosis. If you have osteoporosis, the force of a simple fall to the ground (from the height of a standard chair or less) is often enough to fracture a bone. A simple fall to the ground such as this does not usually cause a fracture in someone without osteoporosis. A bone fracture after a minor injury like this is known as a fragility fracture.
Fragility fractures are most commonly of the hip, wrist, and vertebrae (the bones that make up the spine). A fractured bone in an older person can have serious consequences in some people. For example, about half the people who have a hip fracture are unable to live independently afterwards because of permanent mobility problems.
Loss of height, persistent back pain and a stooping (bent forward) posture
These symptoms can occur if you develop one or more fractured vertebrae. A vertebra affected by osteoporosis may fracture even without a fall or significant force on it. The vertebrae can become squashed with the weight of your body. If severe, a bent forward posture may affect your ability to go about your usual daily activities and may also affect your breathing as your lungs have less room to expand within your chest.
How is osteoporosis diagnosed?
Before any symptoms develop
The ideal situation is that osteoporosis is prevented in the first place. If this is not possible, the next best thing is for diagnosis and treatment of osteoporosis as necessary before any symptoms or fracture occur.
At present, there is no national screening programme in the UK for osteoporosis. However, if you are a man over 50, or a woman over 50 who has gone through your menopause, your GP or other health professional may ask you questions to see how many risk factors for osteoporosis (listed above) apply to you. A risk calculator is available to determine your risk of developing osteoporosis depending on the number of risk factors that you have. If you are found to be at increased risk, or your risk is uncertain, you may be referred for a DEXA scan. DEXA stands for dual energy X-ray absorptiometry. It is a scan that uses special X-ray machines to check your bone density. A DEXA scan can confirm osteoporosis.
After symptoms develop
Osteoporosis is often first diagnosed when you break a bone after a minor bump or fall. Even after the first fracture has occurred, treatment can help to reduce your risk of further fractures. If you are thought to have sustained a fragility fracture, you will usually be referred for a DEXA scan to look for signs of osteoporosis. However, sometimes women of 75 or older who have a fracture are assumed to have had a fragility fracture. In this group of women, treatment for osteoporosis may be started without having a DEXA scan first. This is because osteoporosis is so common in this age group.
A newer test to look for osteoporosis is called digital X-ray radiogrammetry (DXR). It is easier to perform than a DEXA scan because it requires less technical equipment. It may sometimes be used as a screening test for osteoporosis. For example, in someone who has broken their wrist after a fall. However, it is not as sensitive as a DEXA scan at picking up all cases of osteoporosis. So, a DEXA scan remains the gold standard test.
What can I do to prevent osteoporosis?
The following may help to prevent, or slow down, bone loss. This advice is for everyone. But, it is particularly important if you are at increased risk of developing osteoporosis. If you already have osteoporosis, the following measures can also help to try to slow down any bone loss.
Exercise can help to prevent osteoporosis. The pulling and tugging on the bones by your muscles during exercise helps to stimulate bone-making cells and strengthens your bones. Regular weight-bearing exercise throughout life is best, but it is never too late to start. This means exercise where your feet and legs bear your body’s weight, such as brisk walking, aerobics, dancing, running, etc. For older people, a regular walk is a good start. However, the more vigorous the exercise, the better. For most benefit you should exercise regularly – aiming for at least 30 minutes of moderate exercise or physical activity at least five times per week. Excessive exercise such as marathon running may not be so good. (Note: because swimming is not weight-bearing exercise, this is not so helpful in preventing osteoporosis.)
Muscle strengthening exercises are also important. They help to give strength to the supporting muscles around bones. This helps to increase tone, improve balance, etc, which may help to prevent you from falling. Examples of muscle strengthening exercises include press-ups and weight lifting but you do not necessarily have to lift weights in a gym. There are some simple exercises that you can do at home.
See separate leaflet called ‘Physical Activity For Health’ which gives more details about exercise.
Food and diet
Calcium and vitamin D are important for bone health. Your body needs adequate supplies of vitamin D in order to absorb (take up) the calcium that you eat or drink in your diet. The recommended daily intake for calcium in adults over the age of 50 is at least 1,000 mg per day. Everyone aged over 50 years should also aim for adequate amounts of vitamin D daily (800 IU). Protein is also important in your diet and one gram a day of protein per kilogram of your body weight is recommended. Briefly:
Calcium – you can get 1,000 mg of calcium most easily by:
- Drinking a pint of milk a day (this can include semi-skimmed or skimmed milk); plus
- Eating 50 g (2 oz) hard cheese such as Cheddar or Edam, or one pot of yoghurt (125 g), or 50 g of sardines.
Bread, calcium-fortified soya milk, some vegetables (curly kale, okra, spinach, and watercress) and some fruits (dried apricots, dried figs, and mixed peel) are also good sources of calcium. Butter, cream, and soft cheeses do not contain much calcium.
Vitamin D – there are only a few foods that are a good source of vitamin D. Approximately 115 g (4 oz) of cooked salmon or cooked mackerel provide 400 IU of vitamin D. The same amount of vitamin D can also be obtained from 170 g (6 oz) of tuna fish or 80 g (3 oz) of sardines (both canned in oil). Vitamin D is also made by your body after exposure to the sun. The ultraviolet rays in sunshine trigger your skin to make vitamin D.
Some people over the age of 50 may need to take supplements if they are unable to get adequate amounts of calcium or vitamin D from their diet or sunlight. In fact, for most people aged over 65, an adequate amount of vitamin D can only be achieved by taking vitamin D supplements. For this reason, a dietary supplement of vitamin D is commonly recommended for people over the age of 65 and for others who may lack vitamin D. For example, people who have a poor diet, or people whose exposure to sunlight is limited, such as those who are largely housebound or women whose whole body is always covered by clothing. If you are unsure about whether you should have calcium or vitamin D supplements, ask your practice nurse or GP.
Smoking and drinking
Chemicals from tobacco can get into your bloodstream and can affect your bones, making bone loss worse. If you smoke, you should try to make every effort to stop. Also, you should try to cut down on your alcohol intake if you drink more than three units of alcohol daily. Separate leaflets, ‘Smoking – Tips to Help you Stop’, and ‘Alcohol and Sensible Drinking’ give further details.
Hormone replacement therapy
Hormone replacement therapy (HRT) contains oestrogen. A few years ago, HRT was widely used to prevent osteoporosis. However, the recent findings on the potential long-term health risks of HRT have meant that it is now not commonly used for this purpose (except in women who have had an early menopause). This is because of the small increased risk of breast cancer and cardiovascular disease (heart disease and stroke) if HRT is used in the long term.
Do I need treatment for osteoporosis?
If you have osteoporosis but have not had a fragility fracture, your doctor will be able to advise whether or not treatment is recommended in your case. They may use a special risk calculator to look at your risk of having a fragility fracture, to help with this decision. This incorporates things such as your age, your bone density measurements on a DEXA scan, and how many other risk factors for bone fractures or indicators for fragile bones that you have. (For example, any history in your family of hip fracture, how much alcohol you drink, your BMI, etc.)
If you are found to have osteoporosis and you have already had a fragility fracture, treatment is usually recommended to help prevent a further fracture. The bisphosphonate drug alendronate is usually suggested first (see below). If alendronate is not suitable or not tolerated, other treatments may be suggested depending on things such as your age, your bone density measurements and how many other risk factors for bone fractures or indicators for fragile bones that you have. Your doctor will be able to advise.
If treatment is started, repeat DEXA scanning on a regular basis may be suggested to look at how effective treatment is. Lifestyle measures and falls’ prevention are important for all people with osteoporosis (see below).
Medication for osteoporosis
Various drugs are available that can help to prevent and treat bone loss. Drugs used to treat osteoporosis include the following.
These are a group of drugs that include alendronate, risedronate and etidronate. They are the most commonly used drugs to treat osteoporosis. They work on the bone-making cells. They can help to restore some lost bone, and help to prevent further bone loss. Research studies have shown that the risk of bone fracture may be reduced by taking one of these drugs if you have osteoporosis. They may also help to reduce the chance of a second fracture if you have already had a fragility fracture.
Alendronate is the drug that is usually used first. Risedronate or etidronate may be considered in certain people who are not able to tolerate alendronate or in whom alendronate is not suitable.
Read the information sheet that comes with the drug as you need to follow the instructions carefully on how to take a bisphosphonate. For example, you need to take bisphosphonate tablets whilst you are sitting up and with plenty of water, as they can cause irritation of your oesophagus (gullet). This can lead to indigestion-type symptoms such as heartburn or difficulty swallowing. Other side-effects may include diarrhoea or constipation. Also, you should not take bisphosphonates at the same time as food. Depending on which drug is used, you may need to take it daily, weekly, or sometimes less frequently.
A rare side-effect from bisphosphonates is a condition called osteonecrosis of the jaw. This condition can result in severe damage to the jaw bone. So, if you take a bisphosphonate and you experience pain, swelling or numbness of the jaw, a ‘heavy jaw feeling’ or loosening of a tooth, you should tell your doctor. Your should also brush and floss your teeth regularly and go for regular dental check-ups whilst taking a bisphosphonate. Tell your dentist that you are taking a bisphosphonate. Note: the risk of osteonecrosis of the jaw is low in people taking bisphosphonate tablets as a treatment for osteoporosis. It is greater in people with cancer who are being treated with bisphosphonates intravenously (into a vein).
This drug may be an alternative for certain people with osteoporosis if a bisphosphonate is not suitable or is not tolerated – for example, because of side-effects. It can help to slow down bone loss and also help to build new bone. Some people develop side-effects with this drug. The most common include nausea (feeling sick) and vomiting.
This drug may be an alternative for women with osteoporosis who have been through the menopause if a bisphosphonate is not suitable or is not tolerated. It is given twice a year by injection and helps to slow down bone loss. Osteonecrosis of the jaw has also rarely been reported with this drug. However, it is thought that in the vast majority of people, the benefits of treatment outweigh the risks.
This is another option for some women with osteoporosis. It is usually only used if a woman has already had a fragility fracture. It works by mimicking the natural effects of oestrogen. This gradually reverses the excessive breakdown of bone that happens at the menopause and makes bones stronger. However, there may be a small increased risk of developing a deep vein thrombosis in some people who take raloxifene. You should discuss this with your doctor.
Parathyroid hormone peptide drugs
These drugs are sometimes suggested for people who have already had a fragility fracture. An example is called teriparatide. Studies have shown that they can reduce the risk of some osteoporotic fractures. But, they only tend to be used if other drugs cannot be tolerated or taken for some reason. Or, if someone has been taking another treatment for one year and they have another fragility fracture and their bone density is getting worse.
Calcium and vitamin D tablets
Your body needs plenty of calcium and vitamin D to make bone. Unless your doctor is sure that you have an adequate intake of calcium and have enough vitamin D, they will often prescribe calcium and vitamin D supplements in addition to one of the above drugs.
Other measures are also important
Medication will not restore all lost bone. Also, medication may not be suggested for all people with osteoporosis. So, there are a number of lifestyle measures that are also important in treating osteoporosis. They include weight-bearing exercise, muscle strengthening exercises, not smoking, and keeping any alcohol drinking to within the levels as described earlier.
You can also take measures to help prevent yourself from falling and of breaking a bone.
- Check your home for hazards such as uneven rugs, trailing wires, slippery floors, etc.
- Regular weightbearing exercise may help to prevent falls (as described above).
- Are your vision and hearing as good as possible? Do they need checking? Do you need glasses or a hearing aid?
- Beware of going out in icy weather.
- Do you take any drugs that can make you drowsy or that may lower your blood pressure too much and increase your risk of falls? Can they be changed? You can discuss this with your doctor.
- Hip protectors may also help in some people. These are special protectors that you wear over your hips that aim to cushion your hips if you do have a fall.
If you have had a fall, or have difficulty walking, you may be advised to have a formal falls risk assessment. This involves various things such as a physical examination, checking your vision, hearing, and ability to walk, reviewing your medication, and reviewing your home circumstances. Following this, where appropriate, some people are offered things such as a muscle strengthening and balance programme, or recommendations on how to reduce potential hazards in their home.
National Osteoporosis Society
Camerton, Bath, BA2 0PJ
Helpline: 0845 450 0230 Web: www.nos.org.uk
References and Disclaimer | Provide feedback
- Osteoporosis – primary prevention, NICE Technology Appraisal Guideline (January 2011); Alendronate, etidronate, risedronate, raloxifene and strontium ranelate for the primary prevention of osteoporotic fragility fractures in postmenopausal women
- Osteoporosis – secondary prevention including strontium ranelate, NICE Technology Appraisal Guideline (January 2011); Alendronate, etidronate, risedronate, raloxifene, strontium ranelate and teriparatide for the secondary prevention of osteoporotic fragility fractures in postmenopausal women
- Osteoporotic fractures – denosumab, NICE Technology Appraisal Guideline (October 2010)
- Guideline for the diagnosis and management of osteoporosis in postmenopausal women and men from the age of 50 years in the UK, National Osteoporosis Guideline Group (October 2008, Updated July 2010)
- Hippisley-Cox J, Coupland C; Predicting risk of osteoporotic fracture in men and women in England and Wales: BMJ. 2009 Nov 19;339:b4229. doi: 10.1136/bmj.b4229. [abstract]
- Kanis JA, Johnell O, Oden A, et al; FRAX and the assessment of fracture probability in men and women from the UK. Osteoporos Int. 2008 Apr;19(4):385-97. Epub 2008 Feb 22. [abstract]
- WHO Fracture Risk Assessment Tool (FRAX®), World Health Organization Collaborating Centre for Metabolic Bone Diseases