The low down on Osteoporosis

1 in 2 women and 1 in 5 men above age of 50 suffer a osteoporosis related fracture in their lifetime. Bone mineral density is a balance between osteoclastic resorption and osteoblastic formation. Numerous hormonal and dietary factors influence the balance between bone production and resorption. However Osteoclasts work faster than osteoblasts leading to bone loss after menopause. Osteoporosis is typically asymptomatic until a fracture occurs, spine and hip fractures are the most common.

What are the risk factors for osteoporosis?

Advancing age (>70 yr), previous fragility fractures, steroid therapy, parental history of hip fractures, low body weight (BMI <20-25), current cigarette use, excessive alcohol consumption physical inactivity are risk factors for osteoporosis.

What are the medical conditions that are associated with osteoporosis?

Endocrine conditions such as hyperthyroidism, hyperparathyroidism, Diabetes mellitus, steroid excess, hypogonadism (primary or secondary to Androgen deprivation therapy), Systemic conditions such as malabsorption (Inflammatory bowel disease, Primary biliary cirrhosis and after gastric bypass surgery), malignancies (myeloma and mastocytosis), Chronic kidney failure, chronic lung disease (COPD), Rheumatogic conditions and drugs such as anticonvulsants, steroids, aromatase inhibitors, cancer chemotherapy, heparin, lithium and hormonal (antihormonal) therapies and infections such as HIV are associated with Osteoporosis.

How is Osteoporosis diagnosed?

Osteoporosis is diagnosed based on the DEXA scan and using an online tool called the FRAX score.

Who should be screened for osteoporosis?

Women older than 65yr and men above 70yrs should be screened. If the age is between 50-69, they can be screened if they have risk factors or if they suffer from conditions mentioned above that cause osteoporosis.

How is the DEXA scan interpreted?

The DEXA scan gives two values, the T score and the Z score (which is the score matched to age and gender). The Z score is used when the DEXA is done for men <50 yrs of age, healthy premenopausal women and children. (Z score of -1 to -2.5 indicate Osteopenia and > -2.5 indicate osteoporosis)

How frequently should the DEXA scan be done?

The recommedatons for the frequency of the DEXA scan is based the result.

How do you interpret the FRAX score?

The T score from the DEXA scan can be misleading as it has been validated only on white women and may not be accurate for others. The WHO therefore developed the FRAX score which gives an estimate of the 10 yr risk of an osteoporotic fracture and could help planning appropriate treatment for the condition.

How is Osteoporosis treated?

1. To correct lifestyle risk factors: patients must be encouraged to eat healthy, stop cigarette smoking and take alcohol in moderation, to exercise regularly (antigravity exercises) and weight loss. A fall assessment must be made and all possible interventions to prevent falls must be made.

2. Calcium and Vit D supplementation: as below

3. Medical management of Osteoporosis?

Initial management would include resorption inhibitors call bisphosphonates. Oral medications include Alandonate, Residronate and Ibandronate. Annual intravenous medications are also available such as Zolendronate. Those intolerant to Bisphosphanates or unresponsive or have contraindications can be started on Denosumab which is a monoclonal antibody directed towards the osteoclast and therefore reduces bone resorption. Denosumab course must be followed by bisphosphonate therapy. Bisphosphonate therapy isnt forever. Oral bisphosphonates must be stopped after 5 yrs and i.v Zolendronate must be stopped after 3 yrs of use (3 annual doses).

If antiresorptive therapy doesnt help anabolic agents such as Teraparatide, Abaloparatide or Romosozumab and Estrogen antagonist such as Raloxifene can be tried. Teriparetide must be stopped after 12-26 months of continuous use and must be followed up with Bisphosphonate therapy.

OSTEOPOROSIS – ALL YOU WANTED TO KNOW!

Osteoporosis is the commonest metabolic bone disease that affects humans. It particularly affects the elderly and is a cause for major morbidity, loss of independence and even death.

 

What is Osteoporosis?

Osteoporosis is a chronic progressive disease of multifactorial aetiology and is characterised by low bone mass and micro architectural deterioration of the bone tissue with increase in bone fragility usually becoming evident after a fracture. It is a serious health issue with devastating physical psychological and economic consequences.

 

 

 How common is Osteoporosis?

Osteoporosis is quite common in the general community. 56% of the women and 18%of the men above the age of 50 Yrs have Osteoporosis.

 

 

How does osteoporosis happen?

The bones of the body are in a constant state of turnover. There is continuous bone resorption and build up. This process is referred to as remodelling. Osteoclasts that resorb bones are modified hematopoietic cells that can remove old bone within a matter of a few. Osteoblasts on the other hand are the cells that rebuild the bone and take a few months to produce new bone. Therefore weakening of the bone could happen quite quickly if the processes that increase Osteoclastic activity set in, as in the case of hormone withdrawal in menopausal women. Aging on the other hand causes osteoporosis by reducing Osteoblastic activity and bone building.

 

 

 

When does Osteoporosis happen?

Bone density reaches a peak around the 3rd decade of life after which it starts to reduce. Osteoporosis becomes evident usually after menopause in women and after the age of 50 in men. Osteoporosis begins much earlier, develops faster and is more severe in women.

 

Women. Men

Bone loss. Earlier and faster. Later and slower

Average bone loss at all sites. 3.4-4.8%. 0.2-3.6%

Fracture risk increased from age. 55 yr. 65 yrs

Mortality after fracture. 17-25%. 31-37%

 

 

What are the symptoms of Osteoporosis?

Osteoporosis is usually a silent disease and usually becomes evident only after a fracture. Pain the back or the hip after minor injury may signify the development of a fracture. 2/3rd of vertebral fractures are painless and they could occur aver very minor trauma. Loss of height or bending (stooped posture) in the elderly may be other symptoms of Osteoporosis.

 

 

 

 

 

 

 When do you start screening for Osteoporosis?

It is recommended that screening is started above the age of 65 yrs for women or after menopause especially with risk factors. In men, it is recommended above the age of 70 yr or if aged between 50-65 yrs only if risk factors are present.

 

 

How is Osteoporosis diagnosed?

The gold standard test for the diagnosis of Osteoporosis is the DEXA scan (Dual Energy X-ray Absorbtiometry). The DEXA scan reports 2 scores. The T score compares the patients bone density to that of a normal person. The Z score compares the patients bone density to that of his peers (the Z score is usually used for Premenopausal women, men <50yrs of age and in children)

 

 

WHO classification of Osteoporosis by DEXA scan

 0 and Above. Normal

-1to -2.5. Osteopenia

Less than -2.5. Osteoporosis

Less than -2.5 with fracture Severe Osteoporosis

 

 

For the Z score <2SD is below what is expected for age gender and ethnicity I.e., is abnormal.

 

What are the other useful tests that are required for Osteoporosis treatment?

The following tests are useful for the management of Osteoporosis:

Complete Blood counts

Liver function tests

Renal function tests and electrolytes

Thyroid function tests

25 hydroxy cholecalciferol assays

Serum Protein Electrophoresis

24 hr Urine calcium to creatinine ratio

Serum Testosterone and LH/FSH assays

DEXA scan

Vertebral X-rays

 

What are the factor that accelerate Osteoporosis ? (risk factors)

There are many risk factors for osteoporosis. They can be broadly divided into the following categories. These risk factors would accelerate the development of Osteoporosis.

1. Age

2. Calcium and Vit D deficiency and protein deficiency

3. Immobility and bed ridden state.

4. Hormonal – Estrogen deficiency (Late menarche, early menopause, surgical menopause)

Male hypogonadal state.  

Diabetes

Acromegaly

Addison’s Disease

  Glucocorticoid excess

Hyperthyroidism

Hyperparathyroidism

Hyperprolactinaemia

Pregnancy

4. Substance abuse – Alcohol intake and smoking

5. Drugs – Anticonvulsants

    Antipsychotics

    Antiretroviral

          Aromatase Inhibitors

    Cytotoxic chemotherapy

      Glucocorticoids

    Heparin

      GNRH/LHRH agonists

    SSRI

6. Post surgery – bariatric surgery

    Gastrectomy

7. Systemic diseases – Congestive Cardiac Failure

  Renal failure

  Cirrhosis of Liver

  Connective tissue disease

  Rheumatologic disease

How is osteoporosis managed?

The first step would be to interpret the DEXA scan.

The FRAX (WHO) score would have to calculated for those with Osteopenia. Treatment would be indicated if the 10yr probability of a Hip fracture was >/= 3% or the 10yr probability of any osteoporotic fracture was >/=20%.

 

All Patients would need to take in adequate Calcium and Vit D supplements and do adequate Muscle strengthening, weight bearing and antigravity exercises.

 

Patients with Osteoporosis or Osteopenia with a high FRAX score would need to be started on pharmacological therapies. While all medicines are approved for women, Bisphosphonates are preferred for men with Osteoporosis.

 

The American Association of Clinical Endocrinologists recommend the following choice of medicines:

1st line – Alendronate, Residronate, Zolendronic Acdid,(reduce both vertebral as well as non-vertebral fractures) and Denosumab (also for steroid induced osteoporosis)

2nd line- Ibandronate (has not been shown to reduce non-vertebral fractures)

3rd line – Raloxifene for women

4th line- Calcitonin

Others: Inj.Teriparetide is reserved for those with high risk for fracture who have failed Bisphosphonate therapy

To treat underlying Hyperparathyroidism and Hyperthyroidism.

Vertebroplasty and Kyphoplasty as indicated for severe pain from fracture vertebra.

 

 

How is Osteoporosis prevented?

Osteoporosis is inevitable with age. However it is believed that certain controllable factors could help in preventing or delaying the onset of osteoporosis. An active lifestyle with adequate outdoor exercise (especially in the Sun), doing antigravity resistance exercises, taking adequate calcium and Vitamin D, avoidance of sedentary lifestyle and Cigarette smoking and excessive alcohol use are all believed to prevent Osteoporosis.  Early detection of bone demineralisation (Osteopenia) and initiation of pharmacologic treatment as well as lifestyle changes can prevent and delay the onset of Osteoporosis.