Osteoporosis PDF

## Osteoporosis **Osteoporosis:** - Low bone mineral density caused by altered bone microstructure. - Caused by imbalance of bone resorption and remodeling resulting in decreased skeletal mass. - Predisposes patients to low-impact fragility fractures. **Failure to reach peak bone mass -> Osteopor...

## Osteoporosis **Osteoporosis:** - Low bone mineral density caused by altered bone microstructure. - Caused by imbalance of bone resorption and remodeling resulting in decreased skeletal mass. - Predisposes patients to low-impact fragility fractures. **Failure to reach peak bone mass -> Osteoporosis Acceleration of bone loss -> Osteoporosis** **Increased resorption -> impaired bone remodeling:** **Clinical profile:** - >50% of postmenopausal women -> osteoporotic fracture -> 33% return to independence. - >50years -> menopause -> loss of estrogen -> bone loss -> most have osteoporosis by 70-80years. - 20% men -> osteoporotic fracture - But, one year mortality post hip fracture -> M:F = 2:1. - Primary osteoporosis: F>M; secondary osteoporosis: M>F. **Common fractures:** - Fracture hip -> doubles every 5 years after 70years of age. - Fracture distal radius -> high risk before 50years -> plateus by 60years and modest age-related increase thereafter. **Types:** **Primary:** - Increasing age. - Decreasing sex hormones. **Secondary:** - Drugs - glucocorticoids, AEDs, chemotherapy, PPI, thiazolinediones. - Disease states - multiple myeloma, malignancy, cushing's, thyrotoxicosis, hyperPTH, GH deficiency, hypogonadism, IBD, malnutriton/malabsorption. - Lifestyle - alcohol, smoking, low BMI, inactivity. **Risk factors for osteoporosis:** - Age (increasing age). - Weight (low body weight). - Smoking. - Past history fracture from minor trauma. - History of osteoporosis. - Early menopause. - Low levels of physical activity. - White/asian race. **Tests:** - Renal function tests; thyroid function tests, Ca, P, Vitamin D. - Bone mineral density -> dual x ray absorptiometry: - Hip - best test more predictive of future fracture. - Spine – first test – picks up early osteoporosis. - T score (<-2.5 -> osteoporosis). - BMD patient vs BMD young adults. - Z score (<-1.5→ rule out secondary osteoporosis). - BMD patient vs BMD age matched controls. **FRAX tool:** - 10-year fracture risk. - Utility: - Need for treatment in osteopenic patient. - Need for DXA in younger (<50years) patients. **Management:** **Treat if:** - Postmenopausal women: - With a recent fracture (risk highest in the initial 1-2years). - At a high risk of fracture (frequent falls (>3/year), elderly, BMD < -3). - FRAX 10-year risk score of ≥ 3% for hip fracture or ≥20% for major osteoporotic fracture. - BMD <-2.5. **Drugs for osteoporosis:** **Bisphosphonates:** - Attach to hydroxy apatite binding sites -> inhibit osteoclastic bone resorption. - Options: Alendronate (70mg once a week), Zolendronate (4mg annually). - Risk reassessment: after 3-5years -> - If low to moderate risk of fractures -> bisphosphonate holiday (upto 5years). - Holiday discontinuation -> decline in BMD; any recent fracture. - If high risk of fractures -> continuation of therapy. - Denosumab - monoclonal antibody to RANKL – 60mg SC Q 6months. - Romosozumab – monoclonal antibody to sclerostin – 210mg SC Q1 month for 1 year. - Teriparatide (recomb frag of hPTH) / abaloparatide (hPTHrP analogue) 20/80mcg SC OD. - SERM - down modulates OC activity – raloxifene 60mg OD/baxedoxifene 20mg OD. **Adjuncts:** - Ca/vitamin D - daily supplementation recommended (especially when other therapies are not possible): - Dose: Ca-1200mg/d (diet + supplement); vitamin D (600-1000U/d). - Role of hormone replacement therapy in postmenopausal women: - <60years, <10years of menopause with vasomotor/climacteric symptoms where BP/Deno CM. Apu - Role of calcitonin: - When all other treatment is C/I: 100IU SC/IM on A/D (200IU nasal spray OD, **In a nutshell:** - Important risk factors for primary osteoporosis: Age & gender. - Important risk factors for secondary osteoporosis: ABCDE: addictions, bowel diseases, cancers, drugs, endocrine diseases. - BMD: T score less than -2.5 ->osteoporosis (Z score <-1.5 requires evaluation for secondary osteoporosis). - Treat in postmenopausal women with recent fracture or high fracture risk; FRAX score >3% risk of hip fracture or >20% risk of major osteoporotic fracture, T score<-2.5. - Mainstay of treatment: bisphosphonates, denosumab‡teriparatide,+ Ca/vitamin D supplements. **Osteoporosis:** - Low bone mass. - Mineral/matrix ratio normal. **Osteomalacea – vitamin D deficiency:** - Defective mineralization. - Low bone mass. - Mineral/matrix ratio low. **Pagets: (Abnormal woven mosaic bone)** - Excessive OC resorption followed by sclerotic bone formation. - Expansile vascular bone. - Mixed lytic & sc) lesions.