Index - 28 - 29 - 30/31 - 32/33/34 - 35 - 36/37/38/39 - 40/41 - 42/43 - 44/45/46 - 47/48 - 49 - 50/51/52/53
54/55 - 56 - 57/58 - 59 - 60/61 - 62 - Pages online: A - B - C - D - E - F - G - References
BONE DISEASE: DIAGNOSIS, PREVENTION AND MANAGEMENT
CONDITION CHARACTERISTICS RISK FACTORS DIAGNOSTIC TESTS

Osteopenia

  • Postmenopausal women and men aged ≥ 50 years T-score –1 to ≥ -2.5
  • Premenopausal women and men aged < 50 years Z-score ≤ -2

Osteoporosis

  • Postmenopausal women and men aged ≥ 50 years T-score < -2.5
  • Premenopausal women and men aged < 50 years Z-score ≤ -2 and fragility fracture
  • Reduced bone mass
  • Increased risk of fractures
  • Asymptomatic until fractures occur

Common in HIV

  • Up to 60% prevalence of osteopenia
  • Up to 10-15% prevalence of osteoporosis
  • Aetiology multifactorial

Consider classic risk factors i
Assess risk score or need for DXA of spine and hip using FRAX® (www.shef.ac.uk/FRAX)

  • Only use if >40 years
  • May underestimate risk in HIV patients
  • Consider using HIV as secondary cause of osteoporosisii
  • Assess risk biannually

If not using FRAX® consider DXA in any patient with ≥1 of: iii

  1. Postmenopausal women
  2. Men ≥ 50 years
  3. History of low impact fracture or high risk for falls iv
  4. Hypogonadism
  5. Oral glucocorticoid use (minimum 5mg prednisone equivalent for >3 months)

DXA scan

Rule out secondary causes if BMD abnormal v

Lateral spine Xrays if low BMD (lumbar and thoracic)
Osteomalacia
  • Defective bone mineralisation
  • Increased risk of fractures and bone pain
  • Vitamin D deficiency may cause proximal muscle weakness
  • High prevalence (>80%) of vitamin D insufficiency in some HIV cohorts
  • Dietary deficiency
  • Lack of sunlight exposure
  • Dark skin
  • Malabsorption
  • Renal phosphate wasting

Measure 25-OH vitamin D in all patients

ng/ml nmol/L
Deficiency <10 <25
Insufficiency <20 <50

If low, check serum calcium, phosphate, alkaline phosphatase and PTH levels
If hypophosphataemic, consider Fanconi syndrome (page 58)
Osteonecrosis
  • Infarct of epiphyseal plate of long bones resulting in acute bone pain
  • Rare but increased prevalence in HIV

Risk factors:

  • Advanced HIV disease (low CD4+ T-cell counts)
  • Glucocorticoid exposure
  • Intravenous drug use
 MRI
i Classic risk factors: older age, female gender, hypogonadism, family history of hip fracture, low BMI (≤ 19 kg/m2), vitamin D deficiency, smoking, physical inactivity, history of low impact fracture, alcohol excess (>3 units/day), steroid exposure (minimum prednisone 5mg or equivalent for >3 months)
ii Although use of HIV as a secondary risk factor in FRAX® has not been validated, including HIV as a secondary cause in a risk assessment will help identify those patients NOT requiring further assessment / DXA
iii If T-score normal, repeat after 3-5 years in groups 1 and 2, no need for re-screening with DXA in groups 3 & 4 unless risk factors change and only rescreen group 5 if steroid use ongoing
iv Falls Risk Assessment Tool (FRAT) (www.health.vic.gov.au/agedcare/maintaining/falls/downloads/ph_frat.pdf)
v Hyperparathyroidism, hyperthyroidism, malabsorption, hypogonadism / amenorrhoea, autoimmune disease, diabetes mellitus, chronic liver disease
 
Management of osteoporosis and vitamin D deficiency
Vitamin D replacement
  • Suggested regimens for vitamin D replacement:
    • 800-2,000 IU daily
    • Can be provided according to national recommendations / availability of preparations (oral and parenteral formulations)
    • Aim to increase serum 25-OH vitamin D >50nmol/L and maintain serum PTH levels within normal range
    • Combine with calcium where there is insufficient dietary calcium intake
Reducing risk of fractures
  • Decrease falls by addressing falls risks
  • Ensure sufficient dietary calcium (1-1.2g daily) and vitamin D (800-2,000 IU daily) intake
  • Refer to national / regional guidelines on treatment of osteoporosis
    • if no guidelines available consider bisphosphonate i treatment in all osteoporotic postmenopausal women and men > 50 years old and those with a history of fragility fracture
    • use bisphosphonate i with calcium and vitamin D replacement
    • no significant interactions between bisphosphonates i and antiretrovirals
    • If on TDF consider renal bone disease (p. 58)
  • In complicated osteoporotic cases (e.g. young men, premenopausal women, recurrent fracture despite bone protective therapy) refer to endocrinologist
  • If osteoporotic and on bisphosphonate i treatment, repeat DXA after 2 years
i Bisphosphonate treatment with either of: Alendronate 70 mg once weekly po; Risedronate 35 mg once weekly po; Ibandronate 150mg oral monthly or 3mg i.v. every 3 months; Zoledronate 5 mg i.v. once yearly