Osteoporosis Pathogenesis and risk factors

Osteoporosis: Pathogenesis and risk factors
Age > 30 (post-peak bone mass) Age-related degeneration
• 4, bone response to N stress; ROS; osteocyte death
Post-menopausal women
estrogen
• 4, anti-resorptive effects of estrogen on OC
• Primary
Bone malignancies (MM, Lymphoma, Leukemia) V PTHrP, IL-6, IL-11, COX-2
RANKL
• OC
GI diseases
Celiac Disease
IGF1 production + 4, Ca2+, vitamin D absorption
IBD
• I` IL-6 • RANKL OC
Chronic liver or kidney disease
• 4, levels of activated serum vitamin D
Lifestyle Factors
CS use

– Smoking – /1\ EtOH – physical activity – poor nutrition
Multiple mechanisms
4, bone formation
• OB
1° endocrinopathies
Hyper-parathyroidism
• I` production of PTH
OC
Hyper-thyroidism
• I` T4 and T3 hormones
Secondary
Authors: Arsalan Ahmad Lance Bartel Reviewers: Reza Ojaghi Usama Malik Dr. Carol Hutchison* * MD at time of publication
Legend:
Pathophysiology Mechanism
OC production and activity + 1, OB production
1
Osteoporosis: uncoupling of bone formation and resorption leading to weak bones
Sign/Symptom/Lab Finding
Complications
Abbreviations: • COX-: Cyclo-oxygenase-• CS: corticosteroid • GI: Gastrointestinal • IBD: Inflammatory bowel disease • IGF1: Insulin-like glucose factor 1 • IL-: Interleukin-• MM: Multiple Myeloma • OB: Osteoblast • OC: Osteoclast • PTH: parathyroid hormone • PTHrP: Parathyroid hormone-related protein • RANKL: Receptor activator of nuclear factor kappa-B ligand pathway • ROS: Reactive oxygen species