Systemic stiffness: a determinant of blood pressure?

1. Systemic stiffness: a determinant of blood pressure? Cuno Uiterwaal Julius Centre Rick Grobbee Julius Centre Ralph Sakkers Paediatric orthopedics Paul Helders Child Physical therapy Ruud Bank TNO/LUMC Raoul Engelbert Child Physical therapy Julius Center for Health Sciences and Primary Care

2. Background blood pressure • early life origin of primary hypertension • blood pressure - arterial wall stiffness • arterial wall stiffness - atherosclerosis • arterial wall stiffness - clinical disease • blood pressure - connective tissue vascular wall Julius Center for Health Sciences and Primary Care

3. Background Blood pressure partly determined by vessel wall connective tissue metabolism • only localized metabolism or systemic? Julius Center for Health Sciences and Primary Care

4. Background Connective tissue: collagen, elastin, crosslinks • many different forms • tissue specific composition/metabolism • some similarities in different tissues Julius Center for Health Sciences and Primary Care

5. Childhood hypermobility syndromes Part of diagnostic tools • Joint hypermobility • skin hyperextensibility Julius Center for Health Sciences and Primary Care

6. Background joint mobility and cardiovascular disease • limited in diabetes mellitus (microangiopathy?) • limited in hypertensives?? • very little research skin extensibility • no research Julius Center for Health Sciences and Primary Care

7. Research question: general Is the relation between blood pressure and tissue stiffness confined to the ardiovascular system? Julius Center for Health Sciences and Primary Care

8. Research question: specific Is blood pressure related to joint mobility skin extensibility muscle strength bone quality in prepubertal children? Julius Center for Health Sciences and Primary Care

9. Childhood determinants of blood pressure • Age • gender • body height • body weight • family BP levels Julius Center for Health Sciences and Primary Care

10. Childhood determinants of joint mobility/skin extensibility • age • gender • body height • body weight • family levels • race Julius Center for Health Sciences and Primary Care

11. Study design: subjects • Cross-section of 95 Caucasian children • two primary school in Zeist (NL) • examined: November 2000 Julius Center for Health Sciences and Primary Care

12. Study design: measurements • anthropometry • blood pressure (OMRON) • joint mobility: goniometry • skin extensibility: standard vacuum pressure • muscle strength: score • bone quality: ultrasound os calcis • questionnaires Julius Center for Health Sciences and Primary Care

13. General characteristics

14. Median (range) joint motion left Julius Center for Health Sciences and Primary Care

15. Median (range) skin extensibility left Julius Center for Health Sciences and Primary Care

16. Blood pressure and systemic stiffness

17. Adjustment: age, gender, weight, height

18. Mutual dependence of various organs

19. Discussion • underpowered study • selection/information bias? • reverse causality? • unknown or residual confounding? Julius Center for Health Sciences and Primary Care

20. Conclusions • Part of the relation between blood pressure and tissue stiffness may be systemic Julius Center for Health Sciences and Primary Care