Osteoporosis is a systemic disease characterized by reduced bone mass, destruction of bone tissue microstructure, increased brittleness of bones and susceptibility to fracture. Osteoporosis is classified as primary osteoporosis (70-85%), secondary osteoporosis (15-20%), and idiopathic osteoporosis (1-2%). Secondary osteoporosis is a metabolic disease with reduced bone mass, destruction of bone microstructure, increased bone fragility and ease of fracture due to disease and medication. Compared with primary osteoporosis, the onset of disease is earlier and younger, and the disease progresses more rapidly and is more harmful. Glucocorticoid therapy and rheumatic immune disease are common causes of secondary osteoporosis.
Glucocorticoids are widely used in chronic inflammatory diseases such as rheumatologic immune diseases, asthma, renal diseases, and hematologic diseases. Glucocorticoid osteoporosis is the most common factor in secondary osteoporosis. The osteoporotic effect of glucocorticoids is most pronounced during the first 6-12 months of treatment, with bone loss estimated to be up to 10-20%, and is dose- and time-dependent and correlated with cumulative dose. Systemic application of >7.5 mg prednisone per day causes more pronounced bone loss than smaller doses of glucocorticoids, and bone trabeculae are more susceptible to damage than the bone cortex. There are no studies to confirm that a safe dose or course of glucocorticoids exists to avoid osteoporosis, with doses as low as 5 mg/d prednisone causing a significant increase in fracture risk, and smaller doses of glucocorticoids also increasing the potential fracture risk to varying degrees, and alternate-day glucocorticoid therapy does not reduce osteoporotic side effects. Several longitudinal studies have shown that glucocorticosteroids start to lose bone mass after a few weeks of treatment, with rapid bone loss in the first few months and a rate of 5-15% after 1 year, and a 30-50% incidence of osteoporosis in patients receiving long-term glucocorticosteroid therapy (more than 1 year).
Common rheumatic immune diseases that lead to secondary osteoporosis include rheumatoid arthritis, systemic lupus erythematosus, dry syndrome, dermatomyositis, and mixed connective tissue disease. where the prevalent factors are related to age, female, menopause, low body weight (BMI), low physical activity and poor lifestyle habits.
I. Disease-specific factors are related to the following factors.
(1) inflammatory mediators mediating cytokines such as IL-1, IL-6, TNF-a, etc. with a role in promoting bone resorption and inhibiting bone formation.
(2) Chronic disease course leading to gastrointestinal absorption dysfunction.
(3) Drug factors such as glucocorticoid therapy.
(4) disease and drug-induced menopause, hypogonadism
(5) Secondary kidney disease, etc.
(6) Diseases leading to dysfunction of the body, reduced activity, etc.
The diagnosis of osteoporosis mainly relies on the detection of bone mineral density (BMD), and the dual-energy X-ray absorptiometry (DEXA) method of BMD is the gold standard for the diagnosis of osteoporosis. Anyone who meets the diagnostic criteria for osteoporosis BMD or the occurrence of brittle bone mass can be diagnosed with osteoporosis. Diagnostic criteria for bone mineral density in osteoporosis: T value ≥ -1 is normal, T value between -1 and -2.5 is bone loss, T value ≤ -2.5 is osteoporosis, T value ≤ -2.5 and at least one fracture is severe osteoporosis.
Second, the clinical manifestations of osteoporosis are.
(1) Bone pain
Mainly manifested as low back pain or circumferential pain, in severe cases, there are difficulties in turning, sitting and walking.
(2) Spinal deformation
Shortening of height and hunchback, reduced mobility, abdominal compression, loss of appetite, and reduced lung function
(3) Fracture
Statistics show that osteoporotic fractures occur in 38% of vertebral fractures, 19% of hip fractures and 19% of forearm fractures, which are the most common and serious complications of osteoporosis. The consequent rise in medical costs brings enormous mental stress and heavy economic burden to society and families. Fractures can seriously affect the life of patients. 85% of patients will experience bone pain when vertebral fractures occur, 91% of patients will have symptoms of restricted movement of the low back, and multiple vertebral compression fractures can lead to hunchback, disability, and affect respiratory function. Hip fractures hit patients even harder. One year after a hip fracture, only 20% of patients can fully recover to the ability of daily life before the fracture, 50% of patients have their lower limb function affected after the fracture heals, and 20-40% of patients will have ischemic necrosis of the femoral head after the fracture surgery.
C. Prevention and treatment of osteoporosis.
(1) Lifestyle changes
No smoking, no alcohol, less coffee and strong tea, reasonable dietary nutrition such as a balanced diet rich in calcium, low salt and moderate protein; appropriate outdoor activities and sunshine, reasonable physical exercise (weight-bearing exercise); take fall prevention measures to strengthen the protection of oneself.
(2) Basic treatment
Calcium: The recommended daily calcium intake for adults is 800mg of elemental calcium, for postmenopausal women and the elderly is 1000mg, for pregnant and lactating women is 1200mg per day. Vitamin D: can promote intestinal absorption of calcium and phosphorus, mobilize calcium and phosphorus in the blood as raw materials for new bone production, promote differentiation of mesenchymal cells or bone marrow stromal cells to osteoblasts, promote bone mineralization, and directly inhibit parathyroid hyperplasia and PTH synthesis. The amount of vitamin D recommended by the American Institute of Medicine (1997) is 400IU (10μg)/d for 51-70 years old, 600IU (15μg)/d for >71 years old, and if there is a lack of light, it should be increased by another 200IU per day.
(3) Anti-osteoporosis treatment
Bisphosphonates such as Fosamax, calcitonin, estrogen analogs, estrogen receptor modulators, etc. Bisphosphonates are used in the guidelines as the first-line drugs to prevent and treat osteoporosis. Alendronate is beneficial in improving BMD in patients receiving glucocorticoids and is the first-line agent for the prevention and treatment of glucocorticoid-induced osteoporosis (GIOP). Calcitonin is used as a second-line agent in patients receiving long-term hormonal therapy with reduced BMD (2001 ACR recommendations for the prevention and treatment of GIOP) in patients who are intolerant or unwilling to take bisphosphonates or in patients with contraindications. Patients. Estrogen analogs are mainly used in perimenopausal women and their use is controversial due to safety concerns.