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.
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. Women are more at risk than men because they lose bone material more rapidly, especially after the menopause when their levels of oestrogen fall. (Oestrogen is a female hormone and helps to protect against bone loss.)
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 (a premature menopause).
- 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, this can affect your 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. 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 three to 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.
Why are steroid medicines taken?
Steroid medicines may be taken to treat many different conditions. They work mainly by reducing inflammation and so are used to treat various conditions where inflammation occurs. For example: some autoimmune diseases; some types of muscle, skin, and joint diseases; asthma, etc. Steroids are also used to treat some cancers. The outlook (prognosis) for a number of diseases has improved, sometimes dramatically, since steroids became available.
Steroid medicines are sometimes called cortisone or corticosteroids. They can be taken in many ways. For example, as tablets by mouth, via inhalers to deliver steroid into your lungs, or by creams to rub on to your skin. Long-term steroid medication is needed to treat some conditions and keep symptoms under control. Unfortunately, this long-term treatment can have side effects. There is often a balance between the risk of side-effects against the symptoms and damage that may result from some diseases if they are not treated with steroids. Note: long-term treatment with low-dose steroid inhalers or steroid skin creams does not carry the same risk of serious side-effects as long-term treatment with steroid tablets.
Prednisolone is the common steroid tablet prescribed. See separate leaflet called ‘Steroid Tablets’ which discusses these in more detail. It also goes through the possible side-effects of treatment with steroid tablets. Dexamethasone is another steroid that is sometimes prescribed.
What is steroid-induced osteoporosis?
One of the side-effects of taking a steroid medicine in the long term is that it can increase your risk of developing osteoporosis. The steroid lowers your bone density and increases your risk of developing a fragility fracture.
If osteoporosis is thought to be due in part to taking a steroid medicine, it is known as steroid-induced osteoporosis. In fact, the use of steroid medicines is one of the leading causes of osteoporosis. Between 3 and 5 in 10 people who take steroid medicines in the long term will develop a fragility fracture because of osteoporosis if nothing is done to prevent this.
In general, when we are talking about steroid medicines that can cause steroid-induced osteoporosis, we are talking about long-term treatment (for three months or more) with prednisolone tablets. As mentioned above, long-term treatment with steroid creams does not carry the same risks of steroid-induced osteoporosis. However, long-term use of high doses of inhaled steroids may also increase your risk of developing steroid-induced osteoporosis. For this reason, the dose of steroid in an inhaler is usually kept to a minimum so that it is just high enough to keep your asthma or other respiratory problem under control.
Note: if you are taking long-term high-dose steroid inhalers, your should discuss your risks of developing osteoporosis with your doctor. The rest of this leaflet focuses on long-term treatment with steroid tablets.
How do I know if I am at risk of steroid-induced osteoporosis?
If you are taking long-term steroid tablets, your risk of developing steroid-induced osteoporosis can vary depending on your individual situation. For example, your age, your sex, whether or not you have had a previous fragility fracture, or any other risk factors for osteoporosis that you may have.
If you have been taking steroid tablets for three months or more, or if you are due to start a course of long-term steroid tablets, your doctor may suggest that you have a special scan of your bones, called 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 and look for any signs of osteoporosis. Bone density is low in osteoporosis. Depending on the results of this scan, and any other risk factors that you may have, your doctor will be able to determine your risk of developing steroid-induced osteoporosis. This will be used to decide if you need drug treatment to prevent it (see below).
Certain groups of people may not need to have a DEXA scan before making a decision to start treatment to prevent steroid-induced osteoporosis. For example, older people, or those who have had a previous fragility fracture. This is because their age and/or the fact that they have had a previous fragility fracture puts them at increased risk of having a fragility fracture if they take long-term steroids no matter what their bone density is.
What can be done to prevent steroid-induced osteoporosis?
There are a number of things that can be done to reduce your risk of developing steroid-induced osteoporosis if you are taking steroid tablets for three months or more. These may be things that you can change yourself in terms of your lifestyle, as well as drug treatment or other measures that your doctor may suggest.
Stop smoking, limit alcohol intake and exercise more
Certain lifestyle factors (as described in the list above) can increase anyone’s risk of developing osteoporosis. If you already have one risk factor for osteoporosis (being on long-term steroid tablets), then it is especially important to try to reduce your number of other risk factors.
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 to four units of alcohol daily. Separate leaflets called ‘Smoking – Tips to Help you Stop’ and ‘Alcohol and Sensible Drinking’ give further details.
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 good for 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.
A separate leaflet called ‘Physical Activity For Health’ gives more details about exercise.
Ensure an adequate calcium and vitamin D intake
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. If you are on steroid tablets for three months or more, your risk of steroid-induced osteoporosis can also be reduced by making sure your body has enough calcium and vitamin D.
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 bodyweight 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.
Unless your doctor is sure that you have an adequate intake of calcium and have enough vitamin D, they may prescribe calcium and vitamin D supplements if you are taking long-term steroid tablets. If you are unsure about whether you should have calcium or vitamin D supplements, ask your practice nurse or GP.
Take the minimum dose of steroids possible for the shortest period of time
In general, the higher the dose of steroid tablets taken in the long-term, the higher your risk of developing a fragility fracture. However, saying that, there is not really a safe dose of steroid tablets because even low doses can increase your fracture risk. Talk to your doctor about the dose of steroid tablets that you are taking. Could the amount of steroid be reduced? Is there another way that the steroid medication may be taken rather than as tablets by mouth? For example, steroids applied to the skin or inhaled into the lungs may be possible to treat some conditions. Taking the steroid medication in another way may help to reduce the effect of the steroids on your bones.
How long a course of steroid tablets do you need? You should also discuss this with your doctor. The course of treatment should be as short as possible. However, as mentioned already above, there is often a balance between the risk of side-effects from taking steroid tablets against the symptoms and damage that may result from some diseases if they are not treated with steroids.
Drug treatment may be needed for some people
If you have had a previous fragility fracture, you will usually be offered drug treatment to prevent steroid-induced osteoporosis if you are prescribed long-term steroid tablets (see below for details of drugs used). This is regardless of your age. If you are an older person, you will also usually be offered preventative drug treatment even if you have not had a previous fragility fracture.
Otherwise, whether or not preventative drug treatment will be suggested may depend on your bone density readings if you have a DEXA scan and/or any other risk factors for osteoporosis that you may have. Your doctor will be able to advise for your particular case.
What drugs are used to prevent steroid-induced osteoporosis?
The drugs used are usually a group of drugs called bisphosphonates. They include alendronate (the one most often used), risedronate and etidronate. They work on the bone-making cells. They can help to restore some lost bone, and help to prevent further bone loss.
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.
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, if you experience pain, swelling or numbness of the jaw, a heavy jaw feeling or loosening of a tooth, you should tell your doctor. You 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 to help to prevent steroid-induced osteoporosis. It is greater in people with cancer who are being treated with bisphosphonates intravenously (into a vein).
Calcium and vitamin D supplements are usually prescribed by your doctor at the same time as a bisphosphonate unless they are sure that you are already getting adequate intake.
If you are not able to take a bisphosphonate (for example, if you have a stomach ulcer), or you have severe side-effects from them, a specialist will normally advise about alternative treatment.
Drug treatment to help prevent steroid-induced osteoporosis is usually continued until the steroid treatment can be stopped.
Preventing falls is also important
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 weight-bearing 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; these 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.
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
- 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)
- Civitelli R, Ziambaras K; Epidemiology of glucocorticoid-induced osteoporosis. J Endocrinol Invest. 2008 Jul;31(7 Suppl):2-6. [abstract]
- No authors listed; Management of corticosteroid-induced osteoporosis. Drug Ther Bull. 2010 Sep;48(9):98-101. [abstract]
- Kanis JA, Johansson H, Oden A, et al; A meta-analysis of prior corticosteroid use and fracture risk. J Bone Miner Res. 2004 Jun;19(6):893-9. Epub 2004 Jan 27. [abstract]
- Glucocorticoid-induced osteoporosis – Guidelines for prevention and treatment, Royal College of Physicians of London (2002)