Steroid-induced osteoporosis is
osteoporosis
Osteoporosis is a systemic skeletal disorder characterized by low bone mass, micro-architectural deterioration of bone tissue leading to bone fragility, and consequent increase in fracture risk. It is the most common reason for a broken bone ...
arising from the use of
glucocorticoid
Glucocorticoids (or, less commonly, glucocorticosteroids) are a class of corticosteroids, which are a class of steroid hormones. Glucocorticoids are corticosteroids that bind to the glucocorticoid receptor that is present in almost every vertebr ...
s (a class of steroid hormones) analogous to
Cushing's syndrome
Cushing's syndrome is a collection of signs and symptoms due to prolonged exposure to glucocorticoids such as cortisol. Signs and symptoms may include high blood pressure, abdominal obesity but with thin arms and legs, reddish stretch marks, ...
but involving mainly the axial skeleton. The synthetic glucocorticoid prescription drug
prednisone
Prednisone is a glucocorticoid medication mostly used to immunosuppressive drug, suppress the immune system and decrease inflammation in conditions such as asthma, COPD, and rheumatologic diseases. It is also used to treat high blood calcium ...
is a main candidate after prolonged intake.
Bisphosphonates
Bisphosphonates are a class of drugs that prevent the loss of bone density, used to treat osteoporosis and similar diseases. They are the most commonly prescribed drugs used to treat osteoporosis. They are called bisphosphonates because they h ...
are beneficial in reducing the risk of vertebral fractures. Some professional guidelines recommend prophylactic
calcium
Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to ...
and
vitamin D
Vitamin D is a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and many other biological effects. In humans, the most important compounds in this group are vitamin D3 (c ...
supplementation in patients who take the equivalent of more than 30 mg hydrocortisone (7.5 mg of prednisolone), especially when this is in excess of three months.
The use of
thiazide
Thiazide () refers to both a class of sulfur-containing organic molecules and a class of diuretics based on the chemical structure of benzothiadiazine. The thiazide drug class was discovered and developed at Merck and Co. in the 1950s. The first ...
diuretics, and gonadal hormone replacement has also been recommended, with the use of calcitonin, bisphosphonates,
sodium fluoride
Sodium fluoride (NaF) is an inorganic compound with the formula . It is used in trace amounts in the fluoridation of drinking water, in toothpaste, in metallurgy, and as a flux. It is a colorless or white solid that is readily soluble in water. I ...
or
anabolic steroids
Anabolic steroids, also known more properly as anabolic–androgenic steroids (AAS), are steroidal androgens that include natural androgens like testosterone as well as synthetic androgens that are structurally related and have similar effects t ...
also suggested in refractory cases. Alternate day use may not prevent this complication.
It is also known as glucocorticoid-induced osteoporosis.
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Mechanism
Mechanisms of SIOP include:
* Direct inhibition of
osteoblast
Osteoblasts (from the Greek language, Greek combining forms for "bone", ὀστέο-, ''osteo-'' and βλαστάνω, ''blastanō'' "germinate") are cell (biology), cells with a single Cell nucleus, nucleus that synthesize bone. However, in the p ...
function
* Direct enhancement of
bone resorption
Bone resorption is resorption of bone tissue, that is, the process by which osteoclasts break down the tissue in bones and release the minerals, resulting in a transfer of calcium from bone tissue to the blood.
The osteoclasts are multi-nucleated ...
* Inhibition of gastrointestinal calcium absorption
* Increased
urine calcium
Urinary calcium is calcium in the urine. It is termed -calcuria or -calciuria as a suffix.
Normal amount
In a urinalysis, the normal amount of urinary calcium can be measured in amount per time (commonly per 24 hours). It can also be measured in ...
loss
* Inhibition of
sex steroids
Sex hormones, also known as sex steroids, gonadocorticoids and gonadal steroids, are steroid hormones that interact with vertebrate steroid hormone receptors. The sex hormones include the androgens, estrogens, and progestogens. Their effects are ...
Diagnosis
The diagnosis of osteoporosis can be made using conventional
radiography
Radiography is an imaging technique using X-rays, gamma rays, or similar ionizing radiation and non-ionizing radiation to view the internal form of an object. Applications of radiography include medical radiography ("diagnostic" and "therapeut ...
and by measuring the bone mineral density (BMD). The most popular method of measuring BMD is
Dual-energy X-ray absorptiometry
Dual-energy X-ray absorptiometry (DXA, or DEXA) is a means of measuring bone mineral density (BMD) using spectral imaging. Two X-ray beams, with different energy levels, are aimed at the patient's bones. When soft tissue absorption is subtracted ...
. A clinical diagnosis of SIOP can be made following a
fragility fracture
A pathologic fracture is a bone fracture caused by weakness of the bone structure that leads to decrease mechanical resistance to normal mechanical loads. This process is most commonly due to osteoporosis, but may also be due to other pathologies ...
in a patient taking steroids.
In addition to the detection of abnormal BMD, the diagnosis of osteoporosis requires investigations into potentially modifiable underlying causes; this may be done with blood tests. Depending on the likelihood of an underlying problem, investigations for cancer with metastasis to the bone, multiple myeloma, Cushing's disease and other above-mentioned causes may be performed.
Prevention and Treatment
To prevent steroid-induced osteoporosis, the steroid dose and duration should be as low and as short as possible. All patients on long term glucocorticoids (≥3 months) should be encouraged to do weightbearing exercise, avoid
smoking
Smoking is a practice in which a substance is burned and the resulting smoke is typically breathed in to be tasted and absorbed into the bloodstream. Most commonly, the substance used is the dried leaves of the tobacco plant, which have bee ...
and excess
alcohol
Alcohol most commonly refers to:
* Alcohol (chemistry), an organic compound in which a hydroxyl group is bound to a carbon atom
* Alcohol (drug), an intoxicant found in alcoholic drinks
Alcohol may also refer to:
Chemicals
* Ethanol, one of sev ...
and take fall prevention measures. Daily calcium and vitamin d intake should be sufficient.
DXA
Dual-energy X-ray absorptiometry (DXA, or DEXA) is a means of measuring bone mineral density (BMD) using spectral imaging. Two X-ray beams, with different energy levels, are aimed at the patient's bones. When soft tissue absorption is subtracted ...
scans can be used in combination with the
FRAX
FRAX (Fracture Risk Assessment Tool) is a diagnostic tool used to evaluate the 10-year probability of bone fracture risk. It was developed by the University of Sheffield. FRAX integrates clinical risk factors and bone mineral density at the femora ...
tool to assess the risk of future fractures for decisions on pharmacological treatment. Importantly, FRAX does not take into account the dose and duration of glucocorticoid.
The
International Osteoporosis Foundation
The International Osteoporosis Foundation (IOF), headquartered in Nyon, Switzerland, is a non-governmental organization (NGO) founded in 1998. It was formed from the merger of the European Foundation for Osteoporosis, founded in 1987, and the In ...
and the
European Calcified Tissue Society
European, or Europeans, or Europeneans, may refer to:
In general
* ''European'', an adjective referring to something of, from, or related to Europe
** Ethnic groups in Europe
** Demographics of Europe
** European cuisine, the cuisines of Europe ...
recommend pharmacological therapy for osteoporosis in
postmenopausal women and men ≥70 years, with a previous fragility fracture, or a dose equivalent of prednisone ≥7.5 mg daily for ≥3 months. For premenopausal women and men <50 years taking steroids for ≥3 months, osteoporosis therapy should be considered for those with a history of a fragility fracture. For all others, treatment decisions are individualized based upon patient characteristics and clinical judgement.
References
{{Osteochondropathy
Skeletal disorders