1. Body composition assessment in chronic kidney disease Jamie Macdonald

2. Five levels of body composition 1.Whole body 2.Tissue 3.Cellular 4.Molecular 5.Atomic

3. Why measure body composition in CKD? Muscle wasting is linked with morbidity (Ikizler et al., 1999) and mortality (Kato et al., 2003) Obesity is also associated with outcome (Kalantar-Zadeh et al., 2005)

4. Effects of body composition on functional capacity Hand grip strength Quadriceps strength 30 sec sit stand test Arm lean mass0.760*N/A Leg lean massN/A0.832*0.661* Appendicular lean mass 0.811*0.835*0.625* Data are Pearson’s r correlation coefficients. *, p < 0.001. Macdonald et al., 2004

5. Body composition in CKD CKD patientsControlsp values Bone (kg)2.32.7< 0.05 Fat (kg)25.121.40.652 Lean mass (kg)17.621.5< 0.05 Extra cellular water (L) 16.316.90.614 Intra cellular water (L) 18.322.7< 0.01 Macdonald et al., 2004

6. Whole body level Something is better than nothing! –Weight –BMI Interpret results with caution! –Muscle or fat? (Beddhu et al., 2003) –Reverse epidemiology? (Kalantar- Zadeh et al., 2005) Scales must be calibrated frequently Remove shoes, wear minimal clothing I don’t believe it!!!

7. Traditional techniques Blood biochemistry –Serum pre/albumin –CRP SGA Anthropometry –Skin folds –Circumferences Creatinine kinetics

8. DXA

9. Bioelectrical impedance Macdonald et al., in submission

10. Monitoring progress: functional capacity Rikli & Jessie Jones, Human Kinetics, 2000

11. Future techniques Near infra-red spectroscopy (Kalantar-Zadeh et al., 1999) Bioelectrical impedance –Spectroscopy (Kaysen et al., 2005) –Segmental spectroscopy (Zhu et al., 2006) –Raw electrical data (KDOQI) Ultrasound (Mercer et al., 2005)

12. Thank you