Osteoporosis

1. Osteoporosis • Critical reduction in bone mass to the point that fracture vulnerability increases • Affects cancellous bone more than cortical bone

2. Osteoporosis • Definition: • A disease characterized by low bone mass and structural deterioration of bone tissue, leading to bone fragility and an increased susceptibility to fractures of the hip, spine, and wrist.

3. Common Osteoporotic Fractures • common sites of fractures (1) thoracic vertebrae • crush • Dowager’s hump (2) distal radius (3) neck of femur (hip)

4. Common Osteoporotic Fractures • common sites of fractures (1) thoracic vertebrae • crush • Dowager’s hump (2) distal radius (3) neck of femur (hip)

5. Osteoporosis- Health Implications • Affects 10 million Americans • Estimated cost of 17 billion dollars annually • estimated that these #s will triple by 2060 • ~ 32% of women and ~ 17% of men will suffer hip fracture by age 90 • 12-20% w/ hip fracture die because of complications • Blood clots • Bed ridden • Underlying chronic diseases (heart disease) • pneumonia

6. Osteoporosis- Health Implications • 55% of the people 50 years of age and older, have low bone mass: risk of developing osteoporosis and related fractures • Often thought of as an older person’s disease, it can strike at any age. • Responsible for more than 1.5 million fracturesannually including: • 300,000 hip fractures • 700,000 vertebral fractures • 250,000 wrist fractures • 300,000 fractures at other sites

7. RISK FACTORS FOR OSTEOPOROSIS • Risk Factor High RiskLow Risk family history yes no ethnic background Caucasian African-American Frame size small large Gender female male amenorrhea yes no menopause early late given birth no yes age over 50 yes no

8. RISK FACTORS FOR OSTEOPOROSIS • Risk Factor High RiskLow Risk Weight underweight overweight obesity (fractures, not osteopenia) Physical activity sedentary regular (overtraining) Smoking yes no Calcium intake low high Vitamin D intake low adequate Soft drink intake high low

9. RISK FACTORS FOR OSTEOPOROSIS • Risk Factor High RiskLow RiskFiber intake high moderate Alcohol intake high low/moderate Caffeine high low or none • Coffee (150 mg); tea (100 mg); Coke (50 mg) estrogen low normal parathyroid hormone low normal

10. Exercise and Osteoporosis in Female Athletes?? 15 yrs ago: scientist found some young female athletes had bone loss (osteopenia) in the spine • some had bone mineral content similar to elderly women

11. OSTEOPENIA in Young Female Athletes • 2. Female Athlete Triad (poor nutrition, amenorrhea, bone loss) * occurs in a significant % of population of athletes, active instructors (10 - 40%) * most common in running, gymnastics, aerobics instructors * associated with disturbances in menstrual cycle > reduction in estrogen

12. Exercise and Osteopenia in Female Athletes (continued) Female Athlete Triad (continued) A. Poor overall nutrition - caloric restriction and eating disorders; decrease in dietary Ca2+ • Primary factor B. Overtraining C. Low % body fat? “Set point” below which normal menstrual cycle is disturbed • varies from person to person, nutritional status, etc Result: disrupted menstrual cycle and osteopenia

13. Eumenorrhea: 10-13 cycles per year Oligomenorrhea: 3-6 cycles per year Amenorrhea: fewer than 3 cycles per year or no cycles for the past six months Primary: never menstruated (Delayed menarche) Secondary: menstruation has been present for a variable period of time in the past and has ceased Menstrual Disturbances

14. Exercise and Osteoporosis in Female Athletes (continued) % of sedentary

15. BONE MINERAL CONTENT Dr. J. Wilmore

16. Intervention for Female Athlete Triad • If nutrition, low caloric intake, overtraining, and low % body fat issues are addressed, normal menstrual cycle usually resumes • Partial recovery of bone mass noted (long-term effect unknown?) • Barbara Drinkwater (Pacific Medical School)

17. Intervention for Female Athlete Triad • Education of coaches, athletes to this problem while the athletes are teens is absolutely critical. • Improvement - last 10 years - college + • Concern now - teens, youth sports • Luteinizing hormone (LH; pituitary hormone needed for ovulation) ∆ 6 months before disturbances in menstrual cycle. Screening/prevention tool??? • Blood draws over 24 hours, expensive

18. INTERVENTION FOR OSTEOPOROSIS 1) Prevention - maximize bone growth during growth phase, maintenance phase; some bone loss with age appears inevitable.

19. INTERVENTION FOR OSTEOPOROSIS 2) Exercise - both weight bearing and weight training; however, avoid overtraining

20. INTERVENTION FOR OSTEOPOROSIS 3) Calcium supplementation Good overall nutrition • watch out for: • * yo-yo diets * rapid weight loss

21. INTERVENTION FOR OSTEOPOROSIS 4) Hormone Replacement Therapy Estrogen: post-menopausal, amenorrheic women • Alternative - “Estrogen receptor modulators” or "designer estrogens" - raloxifene (68% reduction in fractures) Ca2+ regulating hormones • calcitonin (nasal spray) • parathyroid hormone

22. INTERVENTION FOR OSTEOPOROSIS (continued) 5) Ensure adequacy of vitamin D 6) Biphosphonates - increased used, builds bone mass; reduces osteoclast activity; most widely prescribed today Studies have shown that a combination of these therapies is more effective than one alone!

23. Studies have shown that a combination of these therapies is more effective than one alone against osteoporosis! Notelovitz et al., 1990