Osteoporosis

Causes

• Age: Bone density naturally decreases after peak bone mass is reached (around age 30).
• Hormone levels:
  • Estrogen: Lower estrogen levels in women after menopause are a significant risk factor.
  • Testosterone: Reduced testosterone levels in men also contribute to bone loss.

• Dietary factors:
  • Low calcium intake: A lifelong lack of calcium plays a role in diminishing bone density.
  • Vitamin D deficiency: Vitamin D helps the body absorb calcium, so a deficiency can weaken bones.

• Medications: Long-term use of certain medications, such as corticosteroids, thyroid hormone replacement, some diuretics, and some anti-seizure drugs, can damage bone.
• Medical conditions: Certain medical conditions increase the risk of osteoporosis, including:
  • Endocrine disorders (e.g., hyperthyroidism, Cushing's syndrome)
  • Gastrointestinal diseases (e.g., celiac disease, inflammatory bowel disease)
  • Rheumatoid arthritis
  • Kidney disease

• Lifestyle factors:
  • Sedentary lifestyle: Lack of physical activity weakens bones.
  • Smoking: Tobacco use contributes to weak bones.
  • Excessive alcohol consumption: Regularly consuming more than 2 alcoholic drinks a day increases the risk of bone loss.

• Family history: Having a parent or sibling with osteoporosis puts you at greater risk.
• Body frame size: Small-framed people tend to have a higher risk because they may have less bone mass to draw from as they age.

Symptoms

• Break a bone: A fracture, especially in the hip, spine, or wrist, is often the first sign.
• Develop vertebral compression fractures: These fractures in the spine can cause:
  • Loss of height
  • Severe back pain
  • Stooped posture (kyphosis or "dowager's hump")

Diagnosis

• Bone densitometry (DXA scan): A dual-energy X-ray absorptiometry (DXA) scan measures bone mineral density (BMD). It is the most common and accurate test for diagnosing osteoporosis. It typically measures bone density in the spine, hip, and sometimes the forearm.
• Medical history and physical exam: Your doctor will ask about your risk factors, symptoms, and any previous fractures.
• X-rays: While standard X-rays can show fractures, they are not as accurate as DXA scans for detecting early bone loss.
• Laboratory tests: Blood and urine tests may be done to check for underlying medical conditions that contribute to bone loss or to rule out other causes of bone loss, such as hyperparathyroidism or vitamin D deficiency.

Treatment

• Prevent fractures
• Slow bone loss
• Increase bone density
• Control pain

• Medications:
  • Bisphosphonates: These are the most commonly used medications for osteoporosis. They slow bone loss and help prevent fractures. Examples include alendronate, risedronate, ibandronate, and zoledronic acid.
  • Monoclonal antibody: Denosumab is given as an injection and helps increase bone density and reduce fracture risk.
  • Selective estrogen receptor modulators (SERMs): Raloxifene helps increase bone density in postmenopausal women and reduces the risk of spinal fractures.
  • Hormone therapy (estrogen replacement therapy): Can help prevent bone loss in postmenopausal women, but is not a first-line treatment due to potential risks.
  • Bone-building medications:
    • Teriparatide and abaloparatide: These medications stimulate new bone formation and are given by daily injection.
    • Romosozumab: This medication is given as a monthly injection and both increases bone formation and decreases bone resorption.
• Lifestyle changes:
  • Diet:
    • Calcium: Adequate calcium intake is crucial for bone health. Adults aged 19-50 need 1,000 mg daily, and women over 50 and men over 70 need 1,200 mg daily.
    • Vitamin D: Aim for 600 IU of vitamin D daily for adults up to age 70 and 800 IU daily for those over 70.
  • Exercise: Weight-bearing exercises (e.g., walking, jogging, dancing) and resistance exercises (e.g., weightlifting) help strengthen bones.
  • Fall prevention: Measures to reduce the risk of falls include:
    • Using assistive devices (e.g., canes, walkers) if needed
    • Making your home safer (e.g., removing tripping hazards, installing grab bars)
    • Improving balance with exercises
  • Quit smoking: Smoking increases the risk of bone loss and fractures.
  • Limit alcohol intake: Excessive alcohol consumption weakens bones.
• Surgery: If a fracture occurs, surgery may be necessary to repair it. For example:
  • Hip replacement
  • Vertebroplasty or kyphoplasty: Procedures to repair vertebral compression fractures.

Screening, Treatment Decisions, and Staying Upright

Osteoporosis is diagnosed far less often than it is present, and treated far less often than it is diagnosed, even after a fracture that should have settled the question. A few practical points close most of that gap.

Who should have a bone density scan

A DXA scan is recommended for all women from age 65, for younger postmenopausal women with risk factors such as low body weight, a parent who broke a hip, smoking, or long-term steroid use, and for men from 70 under most specialty guidance. A T-score of -2.5 or lower is osteoporosis; between -1 and -2.5 is osteopenia, where fracture risk calculators decide whether treatment is worthwhile. Our bone health after 50 article covers what to expect from the scan.

A fracture after 50 is itself the diagnosis

A hip or spine fracture from a fall from standing height means osteoporosis regardless of the T-score, and so does a wrist or shoulder fracture in most cases. Losing more than an inch and a half of height, or developing a stoop, is a reason to image the spine, because most vertebral fractures cause no acute pain and go unrecognized. Each fracture roughly doubles the risk of the next, which is why treatment should start promptly rather than after recovery.

Taking the medication so it works

Alendronate and risedronate have to be taken on an empty stomach with a full glass of plain water, staying upright for 30 minutes, or they are neither absorbed nor tolerated. After three to five years, people at lower risk can take a break from a bisphosphonate because its effect persists in bone; denosumab is different, and stopping it without transitioning to another drug causes rapid bone loss and vertebral fractures. Jaw osteonecrosis and atypical thigh fractures are real but rare, on the order of one per several thousand treated patients, against the hip fractures prevented.

Calcium, vitamin D, and Florida sun

Calcium should come from food first, with supplements only to make up a shortfall. Living in a sunny state does not guarantee adequate vitamin D: sunscreen, indoor days, and darker skin all reduce production, and vitamin D deficiency is common here. A level is checked before treatment begins because a deficiency blunts the medication's effect.

Preventing the fall prevents the fracture

Most osteoporotic fractures follow a fall, so balance training, strength work, a home free of loose rugs and poor lighting, corrected vision, and a review of medications that cause dizziness all count as bone treatment. The fall prevention guide lists local programs. Men are underdiagnosed and under-treated, which the osteoporosis in men article addresses. The NIAMS and the Bone Health and Osteoporosis Foundation publish guidance on screening and treatment.

If you are a woman over 65, a man over 70, or have broken a bone since 50 and never had a bone density scan, schedule one.