Osteoporosis
Objective
At the end of the lecture student will be able to
• Explain osteoporosis
• Define pathogenesis of osteoporosis
• Describe the Factors affecting osteoporosis
• Briefly explain the treatment of osteoporosis
Osteoporosis
Definition
• Clinical
– Loss of bone mass sufficient to significantly increase the risk of fracture
• Diagnostic
– T score – number of standard deviations above or below the mean for a similar healthy 30 year old
· Normal BMD = T: 0 to -1
· Osteopenia BMD = T: -1 to -2.5
· Osteoporosis BMD = T: less than -2.5
– Z score – number of standard deviations above or below the mean for the patients age, sex and ethnicity
Epidemiology of Osteoporosis
• United States
– 10 million individuals with osteoporosis
– 34 million individuals with osteopenia
• Fracture Risks over age 50
– 50% of women will have an osteoporosis-related fracture
– 25 % of men will have an osteoporosis related fracture
• Estimated costs
– Direct health care $14 billion each year
Pathogenesis of Osteoporosis
• Peak bone mass
• Etiology Bone loss
• Age
• Secondary causes
Peak Bone Mass
• Genetically determined
– 70-75%
– Driven by sex hormones during puberty
– Depends on site measured – spine, femur, radius
• Ethnicity
– Chinese American later than Caucasians
• Women
– Peak accrual ages 11-15
– 95 per cent achieved by late teens
• Men
– Peak accrual later teens
– Maximum spine age 20
– Radius and femur by mid twenties
Factors Affecting Peak Bone Mass
• Delay or Failure of puberty
– Primary Hypogonadism
• Turners syndrome
• Klinefelter syndrome
• Absent cervix, uterus, cervix and/or vagina
• Cryptorchidism
• Chemotherapy, Radiotherapy
• Chronic systemic diseases
– Secondary Hypogonadism
• Kallmann syndrome
• CNS tumors, infiltrative disorders
• Malnutrition
• Chronic systemic illness
Etiology of Bone loss in Osteoporosis
Estrogen Deficiency
• Women
– Occurs earlier
– At menopause bone loss rates to increase by 2 to 6 fold
– For subsequent 6-8 years
– Impairs calcium absorption from gut
• Men
– Testosterone declines age
– Estrogen declines age
– Both androgens and estrogen contribute
Fracture Risk with Aging
Secondary Causes of Accelerated Bone-loss/Osteoporosis
• Inherited disorders
– Osteogenesis imperfecta tarda
– Thallasemia
• Amenorrhea
– Eating disorders
– Low weight
– Excess Exercise
– Female athlete triad
• Energy deficiency
• Low bone mineral density
• Amenorrhea
– Premature ovarian failure
• Respiratory
– Cystic fibrosis
• Gastrointestinal
– Celiac sprue
– Post Gastric by pass
– Inflammatory bowel disease
• Renal
– Idiopathic hypercalciuria
– Chronic renal failure
• Post organ transplant
– Immunosuppressive therapy
• Endocrine
– Hyperthyroidism
– Hyperparathyroidism
– Cushing’s syndrome
– Hypogonadism
– Vitamin D deficiency
• Rheumatology
– Rheumatoid arthritis
– Seronegative athropathies
• Lifestyle
– Smoking
– Alcohol
• Drugs
– Glucocorticoids
– Cyclosporine
– Anti seizure medications
• Phenobarbital
• Phenytoin
– Heparin
– Chemotherapy
• Aromatase inhibitors
– Thyroxine
• Over replacement
Diagnosis of Osteoporosis
• Approach to patient
• Investigations
– Bloods
– Urine
– Imaging
– FRAX use
• Calcium and Vitamin D
Osteoporosis Investigations
• Bloods-Basic
– CBC
– Electrolytes and eGFR
– Serum calcium and phosphate
– TSH
– Testosterone (Men)
– Serum protein electrophoresis
– Bone markers (consider)
• Urine
– 24 hour urine
– Volume
– Creatinine and calcium
Bone Mineral Density Testing
• Bone mineral density testing
– Important means of assessing fracture risk
– Not stand alone test
• Other risk factors have impact on fracture risk
– occasionally more significant impact than bone density results alone
– Glucorticoids
• All known risk factors should be considered when deciding to treat patients
– Mostly treating patients based on risk
– No overt disease
• We need better tools for assessing fracture risk
Summary
• Osteoporosis is an important public health problem
• Accurate diagnosis and treatment requires the use of bone densitometry.
• Radiologists play a central role in the diagnosis and management
– of this disease:
– measuring bone density
– diagnosing fractures
– pointing out secondary causes of bone loss
FAQs
1. Can men get osteoporosis?
Yes, men can develop osteoporosis, although it is more common in women.
2. How is osteoporosis diagnosed?
Osteoporosis is diagnosed through bone density tests, with Dual-Energy X-ray Absorptiometry (DXA) being one of the most commonly used methods.
3. What are the most common medications for treating osteoporosis?
Common medications for osteoporosis include bisphosphonates, hormone therapy, and denosumab.
4. Are there natural remedies for preventing osteoporosis?
A balanced diet, regular exercise, and lifestyle changes can help prevent osteoporosis.
5. What is the best age to start focusing on bone health?
It’s never too early to start focusing on bone health, but the earlier, the better. Building strong bones during childhood and adolescence can reduce the risk of osteoporosis later in life.
