Osteoporosis (bone loss)

Osteoporosis (colloquially known as bone loss) is a metabolic disease of the bones. These lose stability as a result of an excessive breakdown of bone substance, which leads to an increased risk of suffering a bone fracture.

Overall, more women than men suffer from osteoporosis - about 80 percent of cases affect women after menopause. In Germany, about seven percent of all women are affected by osteoporosis by the age of 55 and 20 percent by the age of 80. It is estimated that about one in ten German citizens is affected by osteoporosis and that about 130,000 citizens suffer a vertebral or femoral neck fracture due to bone loss. After a longer course of the disease, the bone fractures and their subsequent complaints are a frequent cause of elderly people being dependent on help in their daily lives.

If fractures have already occurred, the treatment of osteoporosis is difficult. The most important measure is the prevention of bone loss.

Basic knowledge about bones and osteoporosis

The bones of the body are made up of a form-giving tissue (matrix) in which the minerals calcium and phosphate are stored. These minerals are responsible for the hardness and density of the bone.

Bone tissue is a compound of living bone cells. This allows for a constant building, breaking down and remodeling process of the bone. In the first 40 years of life, the build-up processes usually predominate - but then a turnaround takes place and more bone mass is visibly broken down than built up again, causing the bone to lose stability. The formation and breakdown of bone tissue is regulated by the following hormones, among others:

• Vitamin D: promotes the storage of calcium in the bones.
• Calcitonin: this hormone is produced in the thyroid gland and also promotes the storage of calcium in the bones.
• Parathormone: this hormone is produced in the parathyroid gland and causes calcium to be dissolved out of bone tissue
• Oestrogen/testosterone: these sex hormones influence the formation and effectiveness of the hormones mentioned above (vitamin D, calcitonin, parathormone).

Cause of osteoporosis

The cause of osteoporosis is that the regulatory mechanism of the bone tissue is disturbed to such an extent that the degradation processes in the bone predominate. As too little calcium is now stored, the bone matrix becomes holey, thinner and less stable over time. As a result, there is an increased risk of bone fractures. The fractures themselves, as well as the progressive destruction of the bones, can cause severe pain.

In most cases, osteoporosis is caused by a lack of estrogen in menopausal (post-menopausal) women. Men, on the other hand, are very rarely affected by bone loss due to testosterone deficiency. In women, the first bone fracture as a result of osteoporosis can occur about ten years after the decrease in estrogen production during menopause. The vertebral bodies and the neck of the femur are frequently affected.

Senile osteoporosis in people over the age of 70 is another common form of osteoporosis. Both women and men are equally affected by senile osteoporosis. The cause of bone loss is usually a lack of exercise and a deficiency of calcium and vitamin D due to old age. Those affected often suffer a fracture of the neck of the femur.

Favouring factors

Factors that restrict the regular, stable development of bones up to the age of 40 have a favourable effect on the development of osteoporosis. The following risk factors have the greatest influence on the development of osteoporosis:

• Late onset of the first menstrual period (technically known as menarche), early onset of menopause (menopause ), or an ovariectomy(removal of the ovaries) during the fertile stage of life shortens the period during which bone-protecting sex hormones are produced.
• A lack of exercise increases bone loss.
• Diets, high coffee consumption, laxative abuse and a diet very rich in phosphates cause an undersupply of vitamin D and calcium in the body, which has a favourable effect on bone loss.
• Slender people are more often affected by osteoporosis than corpulent people.
• It is assumed that genetic factors can also promote the development of osteoporosis, as bone loss can also occur more frequently within a family.

Secondary osteoporosis

Secondary osteoporosis is when bone loss is caused by other diseases or by taking certain medications. Examples of triggering factors of secondary osteoporosis are:

• Hyperthyroidism: this is an untreated hyperthyroidism - due to the high concentration of thyroid hormones in the blood, the metabolism is accelerated, thus promoting bone loss.
• High cortisol levels: Since cortisol is a natural counterpart of the sex hormones, excessive concentrations of cortisol in the blood (for example, as a result of Cushing's syndrome or long-term treatment with cortisone) promote the development of osteoporosis. However, inhaled cortisone preparations in asthma therapy have no negative effect on bone strength.
• Hyperparathyroidism: This is an overactive parathyroid gland. In this case, too much parathormone is produced, which causes more calcium to be dissolved from the bones. As a result, the development of osteoporosis is promoted.
• Certain diseases of the digestive tract: Long-standing diseases of the intestine (for example ulcerative colitis or Crohn's disease) or of the pancreas, as well as anorexia, prevent sufficient vitamin D and calcium from being absorbed with food. Avoiding dairy products in the case of lactose intolerance can also lead to a calcium deficiency.
• Growth hormone deficiency: Growth hormone regulates length growth and has a major impact on skeletal ossification - if deficient, bone formation may be impaired.
• Certain kidney diseases: Long-standing renal insufficiency (kidney weakness) as well as diabetes mellitus (elevated blood sugar) can lead to excessive excretion of calcium in the urine. In order to maintain the vital calcium level in the blood, the parathyroid gland produces more parathormone, which causes more calcium to be released from the bones.
• Certain joint diseases: Diseases such as rheumatoid arthritis, lupus erythematosus, and ankylosing spondylitis can cause bone damage.
• Alcohol abuse: Alcohol abuse damages the liver, causing it to be unable to produce enough cholesterol (the basic building block for osteoporosis-preventing sex hormones).
• Smoking: In smokers, the bone tissue is damaged by the poorer blood supply - the loss of bone tissue is about twice as high as in people who do not smoke.
• Hypogonadism: This refers to an underactivity of the gonads (ovaries, testicles). In this case, insufficient amounts of the osteoporosis-preventing sex hormones oestrogen and testosterone are produced.
• Tumours: In exceptional cases, these can negatively influence the hormones that regulate bone metabolism.

Initially, osteoporosis usually causes little or only mild symptoms, such as back pain. Spontaneous fractures - the occurrence of bone fractures without a particular trigger - are characteristic of the progression of osteoporosis. Spontaneous fractures cause severe, sudden pain and lead to bone misalignment, which can result in severe muscle strain.

Femoral neck fractures (bone fractures in the area between the head of the femur and the thigh bone) are typical of old-age osteoporosis. Vertebral body fractures are characteristic of hormone-induced bone loss. Due to the relatively young age of osteoporosis patients, the pain is often misinterpreted as "lumbago". As a result of the vertebral body collapses, patients become smaller and smaller over time and develop a hunchback (colloquially known as a "widow's hump").

Nowadays, to diagnose osteoporosis, a so-called osteodensitometry (measurement of bone density) of the femur and the lumbar spine is usually carried out after the anamnesis (medical interview) and the physical examination. The results of the bone density measurement can then be used to make statements about the risk of bone fractures. In addition, a laboratory blood test and an X-ray of the thoracic spine and the lumbar spine can also be helpful. This examination procedure is referred to as the basic diagnosis of osteoporosis.

Performing this basic diagnostic test is recommended for the following people who are most likely to have a greater than 20 percent risk of suffering a femoral neck fracture within ten years:

• If an osteoporosis-type fracture of the vertebral bodies occurs before the age of 60 in men and before the age of 50 in women , or if cortisone is administered for a period of more than three months, and if certain metabolic diseases such as Cushing's disease or hyperparathyroidism are present.
• If an osteoporosis-typical vertebral body fracture occurs in women between 50 and 60 years of age and in men between 60 and 70 years of age.
• In men between 70 and 80 years of age and in women between 60 and 70 years of age, if an osteoporosis-type vertebral body fracture or at least one risk factor is present. Examples of risk factors would be: a fracture after a minor injury, being underweight, smoking, or frequent falls.
• All men over the age of80 and women over the age of 70.

There are no recommendations for the workup of secondary osteoporosis. These causes require specific investigation.

Basic treatment and preventive measures

The most important basic treatment and preventive measures for osteoporosis are sufficient exercise and a proper diet.

No top sporting achievements are necessary - even regular walks, backstroke twice a week for half an hour or water gymnastics result in a more stable build-up of the bones. Strength and endurance training twice a week is very effective.

In terms of diet, care should be taken to consume plenty of calcium (up to one and a half grams per day). Dairy products or mineral water containing calcium are good choices.

Sufficient vitamin D is an important protection against osteoporosis. Eggs, fish, butter and milk in particular contain high concentrations of vitamin D. In addition, the body produces its own vitamin D with the help of UV radiation - so older people in particular should make sure they spend at least 30 minutes a day in daylight. UV radiation is sufficient for the production of the vitamin even under cloudy skies.

Furthermore, non-smokers have a lower risk of osteoporosis.

Since phosphates inhibit the incorporation of calcium into bones and thus promote bone loss, excessive consumption of phosphate-containing foods should be avoided. High concentrations of phosphates are found in meat, sausage products, soft drinks (such as cola) and processed cheese. Phosphates can also be identified in the list of food additives by the designations E338-341 and E450.

Drug therapy

The basic treatment of osteoporosis is a daily intake of about one to one and a half grams of calcium and at least 400 international units of vitamin D. If the body's need for these substances is not met, the patient is given a daily dose of calcium. If the body's need for these substances cannot be met by food alone, they can also be substituted in the form of tablets.

Various medications are used to prevent bone fractures due to osteoporosis in post-menopausal women. These should be taken for at least three to five years, or longer if necessary.

The following are the drugs of choice for the treatment of osteoporosis:

• Bisphosphonates: these substances counteract excessive breakdown of bone tissue and also have the effect of strengthening existing bone mass. Depending on the preparation, bisphosphonates are administered once a day, weekly or monthly in the form of tablets. It is also possible to administer bisphosphonates only once a year by means of an infusion.
• SERM (Selective Estrogen Receptor Modulators): These prevent the breakdown of bone tissue and have a regulating effect on bone metabolism. The drug must be taken every day.
• Strontium Ranelate: This active substance prevents excessive breakdown of bone tissue and promotes the activity of osteoblasts (bone-building cells). It is a powder that is taken once a day dissolved in water.
• Teriparatide: This is a fragment of the hormone parathyroid hormone produced in the parathyroid gland. Teriparatide helps build bone and promotes the formation of new bone tissue. The active ingredient can be injected under the skin once a day for a maximum of 18 months in post-menopausal women who are at particularly high risk of bone fracture.

In men suffering from osteoporosis, the active substance alendronate (a bisphosphonate) has been used up to now.

Precautions

Because patients with osteoporosis are at greatly increased risk for bone fractures, the following measures and precautions should be observed:

• The home should be furnished to reduce the likelihood of falls (for example, no slippery carpets, no thresholds on the floor, good lighting). Also, only flat slippers with non-slip shoe soles should be worn.
• Do not lift heavy weights.
• When there is black ice on the roads, the home should only be left for absolutely essential errands - it is advisable to have your shopping delivered.
• Vision should be checked regularly by an ophthalmologist and vision aids should be adjusted if necessary.
• Certain medications, such as sleeping pills, allergy medications, antidepressants and antihypertensives (for high blood pressure), can reduce responsiveness and increase the risk of falling.
• Osteoporosis self-help groups offer advice and help.

If osteoporosis is left untreated, the disease progresses and over time can lead to multiple fractures and extremely severe pain, for example in the lumbar spine. Due to the limited mobility caused by the bone damage and the permanent pain, osteoporosis can lead to disability and make patients dependent on constant care - often a move to a nursing home is unavoidable.

In most cases, osteoporosis would be preventable with good prevention. If bone loss already exists, consistent treatment can inhibit the progression of osteoporosis, reducing the risk of fractures.

The most successful measure against osteoporosis is good prevention. The following factors should be taken into account:

• If there are several risk factors for osteoporosis, it should be discussed with the doctor whether preventive treatment with medication should possibly be carried out.
• Regular exercise increases bone mass, which can help prevent osteoporosis.
• When eating, care should be taken to ensure that a lot of calcium is consumed. Milk and dairy products as well as mineral water containing calcium are suitable for this purpose. However, no more than one and a half grams of calcium should be consumed per day.
• Vitamin D is an important protection against osteoporosis. Eggs, fish, butter and milk in particular contain a lot of vitamin D. In addition, the body produces its own vitamin D by means of UV radiation - so older people in particular should make sure they spend at least 30 minutes a day in daylight. UV radiation is sufficient for vitamin production even under cloudy skies.
• Use of table salt that also contains fluoride.
• Foods containing phosphates should only be consumed in small quantities, as excessive amounts of phosphates inhibit the incorporation of calcium into the bones and thus have a reinforcing effect on osteoporosis. High concentrations of phosphates are found in meat, sausage products, soft drinks (such as cola) and processed cheese. Phosphates can also be identified in the list of food additives by the designations E338-341 and E450.
• Additional risk factors for osteoporosis are smoking and excessive alcohol consumption.

Prevention of bone fractures

Since the bones break particularly easily in the case of existing osteoporosis and subsequently heal poorly, the prevention of falls and bone fractures is also of particular importance.

In old people's homes and nursing homes, osteoporosis patients are often given hip protectors to reduce the risk of fractures of the neck of the femur. This is a special type of underwear in which hard or soft protective elements are incorporated at the sides to act as shock absorbers in the event of a fall.

For affected persons who do not live in old people's or nursing homes, there is currently no recommendation for the use of hip protectors.