Description

A skeletal disease characterized by low bone mass, with disruption of bone architecture leading to compromised bone strength and risk of fracture

Epidemiology

• Predominant age: elderly >60 years of age
• Predominant sex: female > male (80%/20%)

Incidence
There are >2 million fractures annually attributed to osteoporosis in the United States.

Prevalence

• >9.9 million Americans have osteoporosis.
• >43.1 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%

Etiology and Pathophysiology

• Imbalance between bone resorption/formation
• Hypoestrogenemia

Genetics

• 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 fragility fracture
• Modifiable:
  • Low body weight (<58 kg or BMI <21)
  • Calcium/vitamin D deficiency
  • Inadequate physical activity
  • Cigarette smoking
  • Excessive alcohol intake (>3 drinks per day)
  • Various medications

General Prevention

• Regularly perform weight-bearing exercise.
• A diet with adequate calcium (1,000 mg/day for men aged 50 to 70 years and 1,200 mg/day for women aged 51+ years and men 70+ years) and vitamin D (800 to 1,000 IU/day)
• 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
  • 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%
  • Evidence is insufficient to recommend screening men; however, the National Osteoporosis Foundation recommends screening men age >70 years, especially if at increased risk.
  • No clear benefit in predicting fractures from repeating bone mineral density (BMD) testing 4 to 8 years after initial screening.

Commonly Associated Conditions

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