The osteoporosis is characterized by loss of bone strength, which predisposes to fracture . In most cases, the bones become weak because of a lack of calcium , phosphorus and other minerals . Osteoporosis makes bones more porous and more likely to fracture during a common fall that, in normal times, would have been inconsequential.
Note that this is not a disease, but a natural process most often related to aging .
Who is affected?
Most of the time, osteoporosis occurs in people aged 65 and over , but it can occur earlier.
It is estimated that in Canada, 1 in 4 women and 1 in 8 men will be affected in their lifetime. From the age of 50 to the end of life, 4 out of 10 women will suffer a fracture due to osteoporosis.
The bones of the hip , wrists and spine are the most common bone fractures due to osteoporosis.
Objective: prevent fractures
Under the new guidelines issued in 2010 by Osteoporosis Canada , doctors must primarily aim to prevent fractures rather than treating osteoporosis at any price . This new orientation is based on the most recent scientific data. Indeed, it turns out that osteoporosis is only one of the many risk factors for fracture. This means that it is possible to have osteoporosis, but a low risk of fracture. Conversely, it is possible to have a high risk of fracture without osteoporosis.
The doctor must make an overall assessment of the patient’s state of health, the drugs he consumes, his family history, his lifestyle, etc. It is only if he deems it necessary that he will propose a bone densitometry test , which measures the bone mineral density . Previously, the decision to treat or not was based primarily on the results of this test.
All data collected is used to establish the probability of a fracture occurring within the next 10 years. Several questionnaires have been developed to allow the doctor to assess this risk. These vary slightly from one country to another and have been tested in large population samples.
It should be noted that a diagnosis of osteoporosis can be made following one of the two following situations:
- a radiological examination , or osteodensitometry test, reveals osteoporosis;
- A fracture occurred because of bone fragility.
When osteoporosis is diagnosed and treated, it is possible to stabilize or improve the condition of the bones to the point of reducing by 50% the risk of fracture.
|The bone densitometry test
The osteodensitometry test allows knowing the bone mineral density (BMD) that is to say the content of various minerals (calcium, phosphorus, etc.) in the bones.
There are several techniques for measuring the mineral density of bones. The most commonly used is two- photon X-ray absorptiometry . This painless examination exposes to very little radiation. The result of this test (the T score) is compared to the average bone mineral density of young adults.
Note, however, that this test does not allow knowing the quality of the structure of the bone. The strength of the bone depends not only on its density, but also on the quality of its structure.
Evolution of bone mass with age
Not all individuals have the same bone “capital”. 3/4 of it is determined by heredity . Good lifestyle habits (exercise, calcium intake, etc.) help preserve this capital and make it grow.
The peak peak bone mass is reached around the age of 35 (see diagram below). It is generally maintained until 40 years. Subsequently, bone mass tends to decline by 1 to 2% per year.
In the 10 years following the onset of menopause , bone loss accelerates by 2% to 3% per year, due to the decline in estrogen production . The loss then stabilizes at about 1% per year.
In the case of men , the loss is more gradual. At age 65, however, their risk of osteoporosis increases and they are more likely to have fractures.
The following graph gives an idea of the evolution of bone mass with age. This is an average curve. Thus, the curve for a particular individual may be different because it depends on her inheritance and lifestyle. For the factors that contribute to the development of osteoporosis, see the At Risk and Risk Factors sections.
In attempting to limit or prevent bone fractures , we mainly want to avoid the consequences: pain , loss of autonomy , reduced quality of life (especially for hip fracture), etc. 20 to 25% of people who have a hip fracture will die in the next year.
The consequences are often more serious for the man who, at equal age, is generally in poorer health than the woman.
Symptoms of Osteoporosis
- Osteoporosis usually causes no symptoms , hence its nickname “silent thief” or “poorly silent”. Often bone loss occurs only after a fracture during a fall;
- One of its first symptoms is sometimes a reduction in size (4 cm or more). This decrease is related to a back curvature caused by sagging vertebrae. This sagging can lead to severe back pain .
People at risk for Osteoporosis
- People over 65 years old ;
- People who have already suffered a vertebral crush or vertebral fracture ;
- People with a family history of fractures caused by osteoporosis;
- Women who have had an early menopause (before the age of 45), for natural reasons or after removal of their ovaries. The production of estrogen, which contributes to the maintenance of bone mass, decreases significantly at menopause. The longer the body’s exposure to estrogen, the lower the risk of osteoporosis. In addition, women who lack estrogen due to a condition called hypogonadism are also at increased risk;
- People with a disease that interferes with the absorption of calcium in the gut (eg, Crohn’s disease);
- Women who had periods of amenorrhea of more than 6 months (except pregnancy);
- People who have already taken oral corticosteroid treatment for more than 3 months. Also, those who have taken or are taking anticonvulsant medications or heparin;
- To a lesser extent, people with rheumatoid arthritis or who have already had hyperthyroidism. These 2 factors are considered minor.
Risk factors for osteoporosis
The following factors increase the risk of osteoporosis . Their effect is cumulative. However, their influence is less important than the factors described in the at-risk section.
- Lack of physical exercise ;
- A diet low in calcium throughout life;
- A lack of vitamin D caused by limited exposure to sunlight or a diet low in vitamin D. This vitamin is essential for calcium metabolism;
- A significant weight loss (more than 10% of body weight) before the age of 25, or a weight of less than 60 kg (132 pounds);
- Excessive consumption of alcohol ;
- A large consumption of caffeine (coffee, chocolate, colas, energy drinks). Caffeine would increase calcium loss by increasing urine output. Experts usually recommend that older adults, in addition to ensuring adequate calcium and vitamin D intake, not drink more than 3 cups of coffee a day .
|The majority of expert panels, including Osteoporosis Canada, recommend that the following individuals undergo a thorough assessment of fracture risk by a physician, as mentioned at the beginning of this sheet:
In some special cases, for example in the case of rheumatoid arthritis, screening may be offered before the age of 50.
|Basic preventive measures|
|The following 3 measures are the most important. It is also good to avoid the risk factors described above as much as possible.
Exercise. Studies show that exercise is good for the bones, throughout life. Being active during childhood and adolescence is particularly important, because it allows building a more resistant skeleton, so to make reserves of bone mass that will serve in adulthood. Physically fit people develop better balance and coordination, which reduces their risk of falling.
It is recommended to practice a minimum of 30 minutes of physical activity at least 3 times a week . What matters most is not the duration of the sessions, but their frequency.
Here are the various types of recommended exercises .
Eat foods rich in calcium. Almost all cells in the body need calcium to work well. Having a diet that contains enough calcium helps to meet the needs of the body without having to tap into its reserves, that is to say the bones. Sufficient calcium intake can be achieved by regularly eating dairy products, salmon (with bones), sardines, dark green vegetables (broccoli, etc.), soy products (tofu, soy milk) enriched with calcium).
Have a sufficient intake of vitamin D. This vitamin is vital for the health of bones and teeth. It improves the absorption of calcium in the intestine and helps to fix this mineral in the bones. Its active form is synthesized in the skin when it is exposed to the ultraviolet rays of the sun. There is little vitamin D in food in its active form, except in fish (sardine, mackerel, herring, salmon, etc.). That’s why, in North America, milk and margarine are fortified with vitamin D. Some cereals and some rice or soy beverages are too.
|Other preventive measures|
|Calcium and vitamin D supplements
Here are the recommendations made by Osteoporosis Canada :
Medical treatments for osteoporosis
The basic treatment combines taking supplements and proper medicationwith a proper exercise program . On the other hand, the bone loss may reappear when the treatment is stopped.
If osteoporosis is the result of prolonged use of a drug (corticosteroid therapy, etc.), the cause must be eliminated quickly.
There are several medications that can stop bone degeneration , while significantly reducing the risk of fractures . In addition, it is often possible to recover some of the bone mass lost. (Note that the risk of fracture can be reduced even in situations where bone mass remains stable.) Medications are used only when the risk of fracture is considered high.
Here are the main ones:
- The bisphosphonates . These drugs slow down the loss of bone mass. The most used are alendronate (Fosamax) and risedronate (Actonel), in weekly or daily doses in tablet form. A new formulation of Actonel allows you to take this medicine once a month. Etidronate (Didrocal) is also used in daily doses, as well as zoledronic acid administered intravenously once a year.
Side effects . Prolonged intake of bisphosphanates for more than 5 years increases the risk of atypical fracture of the femur . Atypical fractures are located elsewhere on the bone than those caused by osteoporosis. The risk of osteonecrosisof the jaw also increases, especially in women whose immune systems are weakened. These side effects are rare , but serious. According to a study published in 2011, the atypical fracture affects 0.4% of women after 5 years of treatment with bisphosphanates .
According to experts, the use of these medications should be reserved for women whose risk of osteoporosis-related fracture is high (based on the overall medical assessment and not just the bone density test). In these women, the benefits of bisphosphanates clearly outweigh the risks of adverse effects. Some recommend taking a break of 1 year or 2 after a 5-year treatment, then resume it afterwards.
- The calcitonin (Miacalcin). This hormone produced by the thyroid gland slows bone loss. It also provides an analgesic effect. It can be used nasally or as an injection.
- The Raloxifene (Evista). This medicine mimics the effects of estrogen by acting on the receptors of these hormones (but without increasing the risk of suffering from hormone-dependent cancer).
- The tamoxifen . This synthetic hormone, used to treat breast cancer, also has an effect similar to that of estrogen on bones.
- The synthetic parathyroid hormone (PTH). This hormone secreted by the parathyroid glands is reserved for cases of significant osteoporosis. It is administered as an injection. It plays a role in the body’s exchanges of calcium and phosphorus, and slows bone loss.
In case of acute or chronic pain , analgesics will be used . Wearing a corset may be necessary if the pain intensifies.
Note. The hormone replacement at menopause may help slow bone loss and reduce fracture risk. On the other hand, it is rarely used for this unique purpose because of the risks involved. It should be noted that, at the time of cessation of hormonal treatment, an accelerated phase of bone mass loss begins, as naturally observed in women during the years preceding menopause. For more information, see our Menopause fact sheet. Moreover, in the case of men whose osteoporosis results from testosteronedeficiency (hypogonadism), androgen hormone therapy is sometimes used.. This type of hormone therapy also carries risks, such as an increased risk of prostate cancer.
In case of hip fracture , surgery is often required to rebuild the hip.
In case of hyperparathyroidism , removal of the parathyroid glands improves the mineral density of the bones.
Calcium and vitamin D supplements
The doctor sometimes proposes taking supplements of calcium and vitamin D. intake of calciumderived from food and need a supplement is expected to reach 1200 mg per day. The proposed dose of vitamin D varies between 800 IU and 2000 IU (20 to 50 μg) per day, as appropriate.
Measuring blood levels of vitamin D (25-hydroxycholecalciferol) is usually suggested to people who are receiving pharmacological treatment for osteoporosis. The doctor can know the optimal dosage of vitamin D supplements.
As described in prevention, it is good to increase his intake of foods rich in calcium and vitamin D . It is also important to ensure adequate protein intake, and to favor an alkaline diet (rich in fruits and vegetables).
The benefits of physical exercise are numerous:
- preserve mobility and balance;
- prevent falls;
- slow down bone mass loss
- Reduce the pain caused by a fracture.
If you have osteoporosis , you should consult a doctor or kinesiologist before practicing any kind of physical activity . The physical activity program must be progressive and well adapted to the abilities. Weight-bearing exercises and resistance exercises are the most beneficial. For more details, see the Prevention section.
Prevention of falls
Various factors increase the risk of falls in the elderly, such as:
- loss of muscle strength
- balance problems;
- visual disturbances;
- Taking certain medications (for example, sleeping pills, anxiolytics, some antidepressants and some allergy medications).
Maintaining good muscle mass and improving flexibility and balance are the best ways to avoid falls. The consultation of an occupational therapist makes it possible to arrange the place of life in such a way as to reduce this risk.
To apply daily
– Have a good posture : straighten your head and keep your upper back straight while keeping your shoulders back and your lower back arched.
– Support the neck with a small pillow while sitting in an armchair or while driving.
– Handle heavy loads correctly : avoid leaning the upper body to grab and lift a load; rather bend your knees and keep your back straight while moving.
– To avoid falls , put a non-slip mat in the bathtub; wear shoes with flat heels and non-slip soles; beware of area rugs, slippery surfaces and loose wires, etc.
– Pay attention to dogs and cats , as their sometimes unpredictable behavior can cause falls.