MCQ – 29709

All are causes of osteoporosis except –

A.	Old age
B.	Chronic heparin therapy
C.	Hypothyroidism
D.	Thyrotoxicosis

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Correct Answer » C Explanation

Osteoporosis

Osteoporosis is characterized by:

• Reduced bone mass
• Increased bone fragility
• Increased fracture risk

Why C is Correct

Hypothyroidism

• Hypothyroidism generally causes:
  • Reduced bone turnover
• It is not a classical cause of osteoporosis.
• Bone loss is more commonly associated with excess thyroid hormone rather than deficiency.

Reasons to Rule Out Other Options

A. Old age

• Common cause of primary osteoporosis
• Age-related decrease in bone mass occurs due to:
  • Reduced osteoblastic activity
  • Hormonal changes

B. Chronic heparin therapy

• Long-term heparin use causes osteoporosis
• Mechanism:
  • Increased bone resorption
  • Reduced bone formation

D. Thyrotoxicosis

• Excess thyroid hormone increases bone turnover
• Accelerates bone resorption
• Common secondary cause of osteoporosis