Definition
- Progressive, systemic skeletal disease characterized by decreased bone mass and micro-architectural deterioration of bone tissue leading to increased bone fragility and susceptibility to fractures
- Bone strength, reflecting both density and quality of the bone, is compromised thus increasing fracture risk
- Fractures commonly occur in the hip, spine and wrist with the hip fractures having a high morbidity
- Often asymptomatic until patient presents with a fragility fracture
- Osteoporotic or fragility fractures are caused by low-level trauma or mechanical forces that do not usually result in fracture
- Vertebral fracture can cause back pain, height loss and increasing kyphosis
- Primary osteoporosis refers to bone loss which happens after menopause and with aging while secondary osteoporosis is bone loss resulting from diseases or medications (eg glucocorticoids) or is idiopathic
- Though osteoporosis in Asia is very much underdiagnosed and undertreated, it is projected that by 2050, >50% of osteoporotic hip fractures will happen in Asia
- In most developing countries, dual-energy X-ray absorptiometry (DXA) is expensive and is widely unavailable particularly in the rural areas
- Calcium intake in almost all Asian countries is below the FAO/WHO recommendations of 1-1.3 g/day
- Studies done in both sexes and all age groups in different Southeast Asian countries demonstrated widespread incidence of vitamin D deficiency or insufficiency
Glucocorticoid-induced Osteoporosis (GIOP)
- When on oral glucocorticoid therapy, bone loss occurs in the first 6-12 months and fracture risk increases within 3-6 months of initiating glucocorticoids
- Intake of ≥5 mg daily of Prednisolone or its equivalent for ≥3 months is associated with osteoporosis
- Similar risk is also shown with higher glucocorticoid dose taken for a shorter period of time
- Strong glucocorticoids inhaled for 7 years are associated with significant bone loss
- Initial clinical fracture risk assessment is recommended in adults on ≥2.5 mg/day of glucocorticoids for >3 months, who have never had fracture risk assessment or received osteoporosis therapy
Risk Factors
Risk Factors for Fracture and Osteoporosis
Postmenopausal women must be evaluated for risk of osteoporosis
The more risk factors that are present, the greater the risk of fracture
Non-modifiable
- Previous history of fracture as an adult
- History of osteoporotic hip fracture in first-degree relative
- Advanced age
- Poor health/frailty
- Ethnic group
- Early natural or surgical menopause before 45 years of age or prolonged premenopausal amenorrhea >1 year
- Genetics and genetic diseases: Cystic fibrosis, osteogenesis imperfecta, Ehlers-Danlos, hemochromatosis, Marfan syndrome, thalassemia, hypophosphatasia
Modifiable
- Recurrent falls
- Decreased body weight (<57.6 kg [<127 lb] or body mass index [BMI] <19 kg/m2)
- Impaired vision
- Medical conditions: Rheumatoid arthritis, celiac disease, estrogen deficiency, vitamin D deficiency due to lack of sunlight exposure or low intake, thyrotoxicosis, or prolonged Levothyroxine intake, multiple myeloma, bronchial asthma, chronic kidney disease, chronic liver disease, diabetes, epilepsy, human immunodeficiency virus (HIV), hyperparathyroidism, inflammatory bowel disease, malabsorption, neurological disease (Alzheimer’s disease, multiple sclerosis, Parkinson’s disease, stroke), systemic lupus erythematosus
- Cigarette smoking
- Excessive alcohol and caffeine intake (≥3 drinks/day)
- Low calcium intake, excessive salt and vitamin A intake
- Oral glucocorticoid use ≥5 mg/day of prednisone for ≥3 months
- Other medications that increase risk of osteoporosis include anticoagulants, antidepressants, anti-epileptic agents, aromatase inhibitors, GnRH agonists for prostate cancer, Methotrexate, proton pump inhibitors (PPIs), thyroid hormones, thiazolidinediones
- Sedentary lifestyle (lack of physical activity, immobilization)
Factors Associated with Steroid-Related Fractures
- Low bone density
- Cumulative steroid dose
- Age >65 years
- BMI ≤20 kg/m2, significant weight loss
- Smoking, excessive alcohol use
- Diseases associated with low bone density (eg rheumatoid arthritis, inflammatory bowel disease, thyroid disease, hyperparathyroidism, chronic liver disease), sex hormone deficiency
- Family history of osteoporosis, parental history of hip fracture
- History of height loss, fall or fracture and immobilization