A presentation on the need for genetic risk assessment on osteoporosis.

1. Preventing Osteoporosis Taking Care of Your Bones and Joints Dr Dana Elliott Srither MBBS(S’pore), GDFM Family Physician Honorary Secretary Anti-Aging and Aesthetic Medicine Society of Singapore

3. Preventing Osteoporosis www.liferesus.com + www.mydoctor4.me + www.beatitudes.sg + The Aesthetics Clinic

4. Preventing Osteoporosis Evidence of mechanical forces applied to bone induce gene expression in the periosteum leading to an increase in bone size. The number of flights climbed per day has significant effect only on hip bone mineral content. Miles walked per day shows an effect on bone size at femoral neck and total hip. This suggests that there is nearly complete lack of effect of walking or stair climbing on bone mineral content and bone mineral density. www.liferesus.com + www.mydoctor4.me + www.beatitudes.sg + The Aesthetics Clinic

5. Preventing Osteoporosis Bone size of the hip and femoral neck shows significant positive effect of miles walked per day. Because this is an important common fracture site, and because larger bones are generally stronger than smaller bones of equal quality, the effect of walking on bone size may be important in reducing fracture risk. www.liferesus.com + www.mydoctor4.me + www.beatitudes.sg + The Aesthetics Clinic

6. Preventing Osteoporosis Moderate + Vigorous activities among men increases bone cortical surface area and femoral neck bone mineral content, but not in women. Younger women have greater corticol bone mineral density than younger men. Minimal difference in corticol bone mineral density in women who engage between low and high activity level. www.liferesus.com + www.mydoctor4.me + www.beatitudes.sg + The Aesthetics Clinic

7. Preventing Osteoporosis Influence of modarate + vigorous activities is larger in older women than in younger women. Older women with low activity levels have lower corticol bone mineral density than older men, but older women with high activity levels continued to have higher corticol bone mineral density than older men. This suggests that the female skeleton may be more responsive to mechanical loading after menopause. www.liferesus.com + www.mydoctor4.me + www.beatitudes.sg + The Aesthetics Clinic

8. Preventing Osteoporosis Accounting for effects of age, sex and activity levels, genes explained 40-62% of the residual variation in bone mineral content and bone mineral density, and 27-75% in bone size. www.liferesus.com + www.mydoctor4.me + www.beatitudes.sg + The Aesthetics Clinic

9. Preventing Osteoporosis www.liferesus.com + www.mydoctor4.me + www.beatitudes.sg + The Aesthetics Clinic

10. Preventing Osteoporosis Parathyroid Hormone and Vitamin D Through the secretion of parathyroid hormone (PTH), these four small glands regulate how much calcium is absorbed from our diet, how much calcium is secreted by our kidneys, and how much calcium is stored in our bones. 60% of parathyroid hormone is accounted for by genetic influence. www.liferesus.com + www.mydoctor4.me + www.beatitudes.sg + The Aesthetics Clinic

11. Preventing Osteoporosis Parathyroid Hormone and Vitamin D Vitamin D regulates the calcium and phosphorus levels in the blood by promoting their absorption from food in the intestines, and by promoting re-absorption of calcium in the kidneys, which enables normal mineralization of bone . 1,25(OH)D is the most biologically active metabolite of vitamin D. Vitamin D has a genetic component of 43% , and environment ( sunlight and diet ) accounts for 27% . 65% of the variance of 1,25(OH)D is explained by genetic influence. www.liferesus.com + www.mydoctor4.me + www.beatitudes.sg + The Aesthetics Clinic

12. Preventing Osteoporosis Bone Formation Bone-specific alkaline phosphatase (BSAP) is a product of osteoblasts and plays a key role in mineralization of bone. 74% of variation in BSAP is explained by genetic factors. Osteocalcin is produced by osteoblasts as they actively deposit bone. 44% of variation in osteocalcin is explained by genetic factors. www.liferesus.com + www.mydoctor4.me + www.beatitudes.sg + The Aesthetics Clinic

13. Preventing Osteoporosis Bone Resorption Urinary levels of pyridinoline is a biochemical marker for bone resorption. Genetic regulation of bone resorption shows heritability of 59%. www.liferesus.com + www.mydoctor4.me + www.beatitudes.sg + The Aesthetics Clinic

14. Preventing Osteoporosis Calcium Excretion Calcium is reabsorbed in the kidneys. What is not reabsorbed is excreted from the body. A genetic influence on calcium excretion is shown with heritability of 52% . www.liferesus.com + www.mydoctor4.me + www.beatitudes.sg + The Aesthetics Clinic

15. Preventing Osteoporosis What is your genetic risk? www.liferesus.com + www.mydoctor4.me + www.beatitudes.sg + The Aesthetics Clinic