1. “Validation of a dietary Phosphorus Quiz in adults with Chronic Kidney Disease”
Principal Investigator:Arianna Aoun, MS, RD, CSR, LD
Co-Investigator:Janelle Fraley, MS, RD,LD
Research Coordinator/Presenter:Ivana Petrovic
NTRN Fall 2014,
December 1, 2014

2. Background
RDA: mg/d¹
Daily Intake from food additives: 1400mg/d²,³
Renal Restriction: mg/d³,⁴
Serum PO4 goal [CKD Stage 3-5]: mg/dL⁵
Serum PO4 goal [CKD Stage 5D]: Normal Value⁵ [i.e mg/dL⁴]
I will abbrev. phosphorus as PO4. There are organic sources naturally in foods and inorganic phosphates which come from additives. IOM RDA for PO4 is 700 mg/d - most American adults get about mg/d from diet (this is the average and depends on processing of foods, dietary protein content, and phosphorus sources in the diet, as well). The GUT absorbs about 75-80% of the overall PO4 we take in. Remember, the DRIs are for healthy people - It is currently recommended to begin PO4 restriction to about mg/d (about 10-12mg PO4 per gram protein) beginning in Stage 3 in an attempt to slow progression and avoid secondary CVD complications. This table is from the KDIGO CKD-MBD Guidelines and shows when it is appropriate to test for various biochemical indices important in CKD. As an interesting side-note, we measure serum PO4, but 85% of our bodies’ PO4 is within the hydroxyapatite of bone - which leads to my next slide.

3. Background Evidence Model ChronicKidneyDisease -MineralBoneDisorder
(CKD-MBD)
Ca++, PO4,
PTH, Vitamin D
Bone turnover,
mineralization,
volume, linear
growth, strength
Vascular/soft
tissue calcification⁵
Evidence Model
CKD-MBD is a disorder involving mineral and bone metabolism due to CKD. It could present as any of the points on the screen:
Abnormalities Ca++, PO4, PTH, Vitamin D metabolism
Abnormalities bone turnover, mineralization, volume, linear growth, strength
Vascular/soft tissue calcification4
It is important to note that CKD-MBD is NOT the same as Renal ostodystrophy which does involve altered bone physiology, but is just one component of CKD-MBD.
The PO4 complications seen in CKD are added risk factors beyond diabetes, HTN, etc. for CVD
Here is the Evidence Model from the KDIGO CKD-MBD guidelines that shows well-established (solid lines) and possible (dashed lines) metabolic asssociations. The authors note that there are further health implications for bone and CV diseases that are not shown here, for example: pt age and presence of osteoporosis.

4. Background³ No Validated Tools Exist6,7,8
gm protein/kg/day: mg PO4/day:
0.6 gm protein/kg/day mg PO4/day
1 gm protein/kg/day mg PO4/day
1.2 gm protein/kg/day mg PO4/day
1 HD session removes mg PO4.
PO4 binders remove mg PO4/gm.
No Validated Tools Exist6,7,8
GI absorption of organic phosphates: 70-80% animal protein
40-50% plant protein
GI absorption of inorganic phosphates: > 90%
Why does all this matter? We may hand pts lists of foods to avoid (such as this from NCM) or limits to follow, but we really don’t have a validated way to test dietary knowledge of phosphorus in adult CKD patients. /What we currently use

5. Specific Aim #1 Specific Aim 1:
Validate a quiz on dietary PO4 knowledge in adult CKD patients.
Validity Measures:
Construct validity, internal consistency, reproducibility, interpretability,
item difficulty index, floor & ceiling effects
It is expected the quiz is valid, as it is modeled after a validated test and reviewed by subject-matter experts for content and face validity.

6. Specific Aim #2 Specific Aim 2:
Examine demographics and biochemical data of participants to determine validity and generalizability.
Variables:
Age, gender, race/ethnicity, education level, CKD stage, history of elevated serum PO4
Survey, Retrospective Chart Review
It is expected this CKD population to be comparable to others in the US in regards to gathered data.

7. Significance PO4 not commonly listed on Nutrition Facts10
Additives2,3,10
Impact
Bioavailability
Usefulness of a quiz6,11

8. Research Methods12 Quiz A and B / Procedure Participants:
34 High-Knowledge
34 Low-Knowledge
Based on a 3-point difference
Explain Quiz – two forms, paper-and-pencil, self-administered about minutes, real-life choices, while in dialysis or waiting for appt
Participant Inclusion/Exclusion criteria
Content and Face already addressed in previous portion of the research

9. Research Methods12 Types of Quality Measures Statistical Analysis:
Student’s T-test OR Kruskal-Wallis,
Pearson’s Correlation,
Kuder-Richardson 20,
Frequency (average),
Mean ± S.D.
What measures are we looking at (construct validity, reliability/internal consistency, reproducibility, interpretability, item difficulty index and and floor & ceiling if exist) and explain measures/tests

10. Potential Limitations
Does not consider adherence and knowledge
One geographic area (availability of cultural foods and generalizability)
Mostly male population
1. and literature to date is unsure of connection

11. Alternative Approaches
Test in multiple VAs/geographic areas
Increased time if low participation
Other quality measures
Across the whole US, genders, races, education levels=generalizability (external validity?)
We may not attain 34 high- and low-knowledge patients, in which case, the period for data collection will be extended.
Future quality measures to solidify validity.

12. Project Timeline Sept, Oct, Nov 2014: Literature Review
Fall 2014: Write-up of prior RPG subject-matter expert review
Oct 2014: Change of Study Staff/VA IRB requirements
Nov/Dec 2014: Research Proposal
Jan 2015: Mock IRB
Jan 2015: Recruit participants and review charts
Feb 2015: Data collection from patients
Mar 2015: Continue and finish data collection from patients
April 2015: Statistically analyze and interpret results
April/May 2015: Write manuscript and present findings

13. References
1. Standing Committee on the Scientific Evaluation of Dietary Reference Intakes, Food and Nutrition Board, Institute of Medicine. DRI Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride – Phosphorus. Washington, D.C.: National Academy Press ; 1997: Accessed November 5, 2014.
2. Moe SM, Zidehsarai MP, Chambers MA, et al. Vegetarian compared with meat dietary protein source and phosphorus homeostasis in chronic kidney disease. Clin J Am Soc Nephrol. 2011;6(2): doi: /CJN
3. González-Parra E, Gracia-Iguacel C, Egido J, Ortiz A. Phosphorus and nutrition in chronic kidney disease. Int J Nephrol. 2012;2012: doi: /2012/

14. References
4. National Kidney Foundation. KDOQI Clinical Practice Guidelines for Bone Metabolism and Disease in Chronic Kidney Disease. Am J Kidney Disease. 2003; 4(Suppl 3): S1-S201.
5. Kidney Disease: Improving Global Outcomes (KDIGO) CKD–MBD Work Group. KDIGO clinical practice guideline for the diagnosis, evaluation, prevention, and treatment of chronic kidney disease–mineral and bone disorder (CKD–MBD). Kidney International 2009; 76 (Suppl 113): S1–S130.
6. Kesänen J, Leino-Kilpi H, Arifulla D, Siekkinen M, Valkeapää K. Knowledge tests in patient education: a systematic review. Nurs Health Sci. 2014;16(2): doi: /nhs

15. References
7. Brogdon RM. A self-care educational intervention to improve knowledge of dietary phosphorus control in patients requiring hemodialysis: A pilot study. Nephrol Nurs J. 2013;40(4):
8. Ford JC, Pope JF, Hunt AE, Gerald B. The effect of diet education on the laboratory values and knowledge of hemodialysis patients with hyperphosphatemia. J Ren Nutr. 2004;14(1):36-44.
9. Chronic Kidney Disease Stage 5 Nutrition Therapy - Dairy and Other High-Phosphorus Choices. Academy of Nutrition and Dietetics Nutrition Care Manual Web site. Accessed November 17, 2014.
10.Hager MH, Geiger C, Hill LJ, Martin C, Weiner S, Chianchiano D. Usefulness of nutrition facts label for persons with chronic kidney disease. J Ren Nutr. 2009;19(3): doi: /j.jrn

16. References
11. Hand RK, Steiber A, Burrowes J. Renal dietitians lack time and resources to follow the NKF KDOQI guidelines for frequency and method of diet assessment: Results of a survey. J Ren Nutr. 2013;23(6): doi: /j.jrn
12. Baczewski K, Julius M, Kern E. Validation of a paper based dietary potassium test for adults with chronic kidney disease [abstract]. J Ren Nutr. 2010; 20(2): 136.

17. Thank You!
Questions?