1. Coronary Calcification; Body Mass Index (BMI) or Waist to Hip Ratio (WHR) Siamak Sabour, MD, MSc, DSc, PhD, Postdoc Clinical Epidemiologist Persian International Epidemiology Network (PIEPNET)

2. SCIENTIFIC BACKGROUND 1994: M.D, I.R. Iran 2004: M.Sc, Clinical Epidemiology, Erasmus MC, The Netherlands 2006: D.Sc, Clinical Epidemiology, Erasmus MC, The Netherlands 2007: Ph.D, Clinical Epidemiology, UMC Utrecht, The Netherlands 2008 Post doc Cardiovascular Epidemiology Thomas Jefferson University, Philadelphia, PA, USA Post doc Pharmacoepidemiology University of Pennsylvania, Philadelphia, PA, USA 2008 until now Assistant Prof of Clinical Epidemiology & Medicine Sabous S, MD, MSc, DSc, PhD, Postdoc2

3. PURPOSE To examine the relation between 9 years change in Body Mass Index (BMI), Waist-to-Hip Ratio (WHR) and risk of coronary artery calcification (CAC). Sabous S, MD, MSc, DSc, PhD, Postdoc3

4. DESIGN Longitudinal study Sabous S, MD, MSc, DSc, PhD, Postdoc4

5. SUBJECTS 573 postmenopausal women selected from a population based cohort study. Sabous S, MD, MSc, DSc, PhD, Postdoc5

6. METHODS Data on BMI & WHR were collected at baseline (1993-1997) and follow-up (2002-2004). At follow-up, the women underwent a multi-detector computed tomography (MDCT) (Philips Mx 8000 IDT16) to assess coronary artery calcium (CAC). Sabous S, MD, MSc, DSc, PhD, Postdoc6

7. 7

8. 8

9. METHODS The Agatston score was used to quantify coronary artery calcium. Logistic regression models were used to evaluate the relations under study. Sabous S, MD, MSc, DSc, PhD, Postdoc9

10. METHODS Change in BMI & WHR was categorized into four groups: Low at baseline-Low at follow-up (low was defined as below the median) High-Low Low-High High-High Sabous S, MD, MSc, DSc, PhD, Postdoc10

11. RESULTS Compared to subjects whose WHR remained below the median of the distribution at both occasions, those with a WHR above the median at both occasions had a 2.8 [95% CI 1.5 - 5.7] fold increased risk of CAC. Sabous S, MD, MSc, DSc, PhD, Postdoc11

12. RESULTS Women whose WHR rose over the 9 year period from below the median to above the median had a 2.6 [95%CI 1.3 - 5.2] fold increased risk of CAC. Sabous S, MD, MSc, DSc, PhD, Postdoc12

13. RESULTS In contrast, change in BMI was not related to risk of CAC. Sabous S, MD, MSc, DSc, PhD, Postdoc13

14. Sabous S, MD, MSc, DSc, PhD, Postdoc14

15. CONCLUSION Change in WHR over time relates to an increased risk of CAC. However, BMI has no effect on that. Sabous S, MD, MSc, DSc, PhD, Postdoc15

16. Acknowledgments Prof. Diederick. E. Grobbee, MD, PhD Prof. Mathias Prokop, MD, PhD Dr. Yvonne. T. van der Schouw, PhD Prof. Michiel. L. Bots, MD, PhD 1. Julius Centre, University Medical Centre Utrecht, The Netherlands 2. Radiology Department, University Medical Center Utrecht, The Netherlands Sabous S, MD, MSc, DSc, PhD, Postdoc16

17. CONCLUSION Changes in Waist-to-Hip Ratio (WHR) relates to an increased risk of CAC. However, Body Mass Index (BMI), has no effect on that. 17