Description

A skeletal disease characterized by low bone mass, deterioration of bone tissue, and disruption of bone architecture that leads to compromised bone strength and an increased risk of fracture.

Epidemiology

• Most common bone disease in humans
• Predominant age: elderly >60 years of age
• Predominant sex: female > male (80%/20%)

Incidence
There are poor data on the incidence of osteoporosis and osteopenia; however, there are an estimated 9 million fractures annually attributed to osteoporosis worldwide.

• >10.2 million Americans have osteoporosis
• >43.4 million Americans have osteopenia
• Women >50 years of age: osteoporosis 15.4% and osteopenia 51.4%
• Men >50 years of age: osteoporosis 4.3% and osteopenia 35.2%
• One in three women and one in five men will experience an osteoporotic fracture in their lifetime

Etiology and Pathophysiology

• Imbalance between bone resorption and bone formation
• Aging
• Hypoestrogenemia

• Familial predisposition
• More common in Caucasians and Asians than in African Americans and Hispanics

Risk Factors

• Nonmodifiable:
  • Age >65 years
  • Female gender and menopause
  • Caucasian or Asian race
  • Family history of osteoporosis
  • History of atraumatic fracture
• Modifiable:
  • Low body weight (<58 kg or body mass index [BMI] <21)
  • Calcium/vitamin D deficiency
  • Inadequate physical activity
  • Cigarette smoking
  • Excessive alcohol intake (>3 drinks per day)
  • Medications: See “Commonly Associated Conditions”

General Prevention

The aim in the prevention and treatment of osteoporosis is to prevent fracture:

• Regularly perform weight-bearing exercise
• Consume a diet that includes adequate calcium (1,000 mg/day for men ages 50 to 70 years and 1,200 mg/day for women ages 51+ years and men 70+ years) and vitamin D (800 to 1,000 IU/day).
• Evidence is insufficient to recommend daily supplementation with >1,000 mg of calcium and >400 IU of vitamin D₃ for the primary prevention of fractures in community-dwelling postmenopausal women. The U.S. Preventive Services Task Force (USPSTF) recommends against daily supplementation with ≤1,000 mg calcium and ≤400 IU vitamin D₃ for the primary prevention of fractures in this group (1)[B].
• Avoid smoking
• Limit alcohol consumption (<3 drinks per day)
• Fall prevention (home safety assessment, correction of visual impairment)
• Screen (USPSTF recommendations):
  • All women ≥65 years of age (1)[B]
  • Women >50 years of age with a 10-year risk of major osteoporotic fracture (using the World Health Organization’s [WHO] Fracture Risk Assessment [FRAX] Tool) >8.4% (2)
  • The current evidence is insufficient to recommend screening for osteoporosis in men; however, the National Osteoporosis Foundation recommends screening men age >70 years, especially if at increased risk.
  • Limited evidence from good-quality studies found no benefit in predicting fractures from repeating bone mineral density (BMD) testing 4–8 years after initial screening (2).

Commonly Associated Conditions

• Malabsorption syndromes: gastrectomy, inflammatory bowel disease, celiac disease
• Hypoestrogenism: menopause, hypogonadism, eating disorders, functional hypothalamic amenorrhea
• Endocrinopathies: hyperparathyroidism, hyperthyroidism, hypercortisolism, diabetes mellitus
• Hematologic disorders: hemophilia, sickle cell disease, multiple myeloma, thalassemia, hemochromatosis
• Other chronic diseases: multiple sclerosis, end-stage renal disease, rheumatoid arthritis, lupus, chronic obstructive pulmonary disease (COPD), HIV/AIDS
• Medications: antiepileptics, aromatase inhibitors (raloxifene), chronic corticosteroids (>5 mg prednisone or equivalent for >3 months), medroxyprogesterone acetate, heparin, SSRIs, thyroid hormone (in supraphysiologic doses), PPIs