Overview
Osteoporosis is a condition in which bones lose density and strength, making them fragile and prone to fracture from minor falls or stresses. It is often called a silent disease because bone loss occurs without symptoms until a fracture happens. The most common fractures are of the spine, hip, and wrist. Hip fractures in older adults carry significant mortality.
How common is it?
Osteoporosis affects approximately 3.5 million people in the UK. About 1 in 2 women and 1 in 5 men over 50 will have a fracture due to osteoporosis. It causes over 500,000 fragility fractures in the UK annually.
Causes and risk factors
Bone density peaks in the late 20s and declines with age. In women, oestrogen loss at menopause accelerates bone loss dramatically. Secondary osteoporosis follows specific medical conditions or medications.
Common risk factors
- Age
- Female sex (especially post-menopausal oestrogen deficiency)
- Glucocorticoid use (most common secondary cause — any dose for 3 months warrants bone protection)
- Family history of hip fracture
- Low body weight
- Smoking
- Alcohol excess
- Low calcium and vitamin D intake
- Physical inactivity
- Inflammatory conditions: rheumatoid arthritis, IBD
- Malabsorption: coeliac disease
- Hypogonadism
- Hyperparathyroidism, hyperthyroidism
Symptoms
- Usually none until a fracture occurs
- Back pain from vertebral compression fractures
- Loss of height over years (vertebral fractures)
- Stooped posture (kyphosis) from multiple vertebral fractures
- Hip or wrist fracture from a minor fall
When to see a doctor
See a GP after any low-trauma fracture (falling from standing height or less). Also seek assessment if on long-term steroids, have rheumatoid arthritis, or have strong risk factors. Women after the menopause with risk factors should have a FRAX score calculated.
Diagnosis
DEXA scan measures bone mineral density (BMD) at hip and lumbar spine. Results expressed as T-score: -2.5 or below is osteoporosis. FRAX tool calculates 10-year fracture probability combining BMD and clinical risk factors. Blood tests exclude secondary causes.
Treatments
Bisphosphonates
Alendronate (weekly oral tablet) or risedronate are first-line. They reduce vertebral fracture risk by 40 to 50% and hip fracture risk by 40%. Zoledronic acid annual IV infusion for those who cannot tolerate oral tablets.
Denosumab
RANK-L inhibitor given as 6-monthly subcutaneous injection. Potent bone-protective effect, particularly for spinal fractures. Requires continuation (stopping causes rapid bone loss).
Anabolic agents
Teriparatide (PTH analogue) or romosozumab build new bone rather than just preventing loss. Reserved for severe osteoporosis or treatment failure. Romosozumab reduces fracture risk within 12 months.
Calcium and vitamin D
Calcium 1,000 to 1,200mg daily and vitamin D 800 IU daily are essential adjuncts to pharmacological treatment. Ensure adequate levels before starting bisphosphonates.
HRT for postmenopausal women
Oestrogen effectively maintains bone density and reduces fracture risk. Appropriate for women with menopause symptoms who also need bone protection.
Self-care and lifestyle
- Weight-bearing exercise (walking, dancing, low-impact aerobics) and resistance training stimulate bone formation
- Ensure dietary calcium from dairy, fortified foods, leafy greens, and tinned fish with bones
- Take vitamin D supplement (particularly in the UK, where sunlight is insufficient for synthesis 6 months of the year)
- Stop smoking and reduce alcohol
Prevention
Peak bone mass is set by age 30 — adequate calcium, vitamin D, and exercise from childhood determine later fracture risk. Falls prevention (removing trip hazards, balance training, medication review, eye care) reduces fracture risk in older adults.