Cat CKD Study
Gastrointestinal and Hematological Tolerance of a Muscle Powder Supplement in Cats with Chronic Kidney Disease
Korinn Saker, MS, DVM, PhD, DACVIM (Nutrition), Julie Nettifee, Marie Stevenson -North Carolina State University (NCSU) - College of Veterinary Medicine, Raleigh, NC
Introduction
Chronic Kidney Disease (CKD) is diagnosed in 30-40% of cats older than 10 years and up to 80% of cats older than 15 years. Progressive renal dysfunction and lean muscle mass (LMM) loss are common in later stages of CKD; and they adversely affect mobility, immunocompetence, organ function, and overall quality of life.
Early-stage feline renal diets are formulated with restricted phosphorus and adjusted protein levels to help mitigate LMM loss, but chronic kidney dysfunction requires both phosphorus and protein restriction. Fortetropin® (MYOSCORP, Cedar Knolls, NJ), is a proprietary proteo-lipid complex made from fertilized, chicken egg yolk that lowers myostatin concentrations, reduces muscle atrophy in dogs, and increases muscle mass in people. 1-3 Prior studies report high palatability and gastrointestinal tolerance of the supplement in cats. 4
Therefore, this pilot study evaluates the influence of Fortetropin® on renal, gastrointestinal, and muscling parameters in cats with CKD.
This study was approved by IACUC protocol 22-236, North Carolina State University College of Veterinary Medicine.
Hypothesis
Supplementation with a commercial muscle powder product (Fortetropin®) will support lean muscle mass, gastrointestinal tolerance, and maintain serum phosphorus status in feline CKD Stage Il and Ill patients.
Research & Objectives
- Evaluate the gastrointestinal tolerance of Fortetropin® supplementation in feline CKD Stage I| and Ill cats during a 12-week pilot study.
- Monitor the influence of the Fortetropin® supplementation on select renal parameters and lean muscle mass in cats with Stage I| and III
Materials & Methods
Animals: A review of medical records (2018-2022) identified cats that matched CKD staging (http://www.iris-kidney.com/pdf/4 Idc-revised-grading-of-acute-kidney-injury.pdf) and additional inclusion/exclusion criteria (including diet and comorbidities that would complicate the CKD during the study duration.) CKD Stage II (n=6) and CKD Stage III (n=6) were utilized for the 12-week study. The cats were maintained in their home environment under the owner's caregiving.
Study Design: Caregivers were provided with an orientation covering daily supplementation, feeding instructions based on the nutritional assessment (NA) along with a digital gram scale, and guidance for daily diary reporting. Supplement and diary sheets were provided at orientation, and each recheck. Each cat received 2 grams of supplement powder per day mixed into the food. All cats were fed a diet that provided a feline renal disease nutrient profile. Daily supplement was continued until the study end point (day 84) or until the cat demonstrated any adverse gastrointestinal intolerance (persistent vomiting, diarrhea, regurgitation, nausea) or >66% hyporexia of 2 days). If reported, the cat was removed from the study.
The 12-week (84-day) pilot study had subsequent 28-day time points for data collection.
- Study days 0 (first) and 84 (last) included: physical exam (PE); comprehensive NA (including body condition (BCS) and LMM assessment); blood for complete blood count (CBC) and full chemistry profile (fCP); urine collection for urinalysis (UA) and urine protein:creatinine ratio (UPC); and DEXA scan analysis under light sedation to evaluate body composition changes.
- Days 28 and 56 included: PE; comprehensive NA; blood and urine collection.
- Days 28, 56 and 84: Caregivers submitted the daily diary sheets that reported diet and supplement intake/refusal, and any adverse reactions to supplementation for that 28-day period.
Data Analysis: Data are presented on, n=6 each, CKD IRIS Stage I| and Stage Ill cats. Means and percentage changes over time are reported. T-test were run to determine significance (P<0.1) of the average values of select parameters between and within CKD groups.
Results
Table 1: Summary of signalment data for study-n=12 cats
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* All cats spayed or neutered. BW = body weight; cBCS = body condition score on 1/9 scale; F and M = female and male, respectively. Results were considered significant at P ≤0.10.
Table 2: Summary of signalment data for study-n=12 cats
Values represent the averages of select serum and urine renal-focused parameters measured at 28-day intervals in CKD stage ll ana lll cats supplementea with Fortetropine for o4 days. Average change is across o4-day study within a Cau group. P value ≤ 0.1 indicates a difference between the average change in individual CKD groups for each parameter during the 84-day study period. A slight increase (41%) or decrease (42%) in serum phosphorus was noted in cats over time. All values remainea winn our reterence range aespite changes. Unne protemn credumine fauo (ure aecreasea In 30% of the study participants and increased in 17% of cats with no values reflective of proteinuria.
Figure 1:
Values represent the average of select serum and urine parameters measured at 28-dav intervals in CKD stage lI and Ill cats supplemented with Fortetropin® for 84 days. P value ≤ 0.10 indicates a difference between the average change in CKD Stage Il and stage Ill cats for each parameter during the 84-day study period.
Figure 2:
Body composition was measured using DEXA scan (Hologic® systems) on study days 0 and 84. P value ≤ 0.10 represents a significant difference between the change in CKD Stage Il and Ill cats for each parameter.
Summary & Conclusions
Daily Fortetropin® supplementation to cats diagnosed with CKD IRIS Stage I| and III was palatable and gastrointestinal tolerance was high, as only 2 cats experienced a 1-2 day supplement related gastrointestinal intolerance during the 12-week study period.
Serum BUN, Creatinine, and phosphorus, along with urine UPC changed minimally in both CKD groups across the study period. While all values remained within our reference range despite noted increases or decreases.
Lean muscle mass assessment via DEXA scan provided an accurate, quantitative measure of changes, with 67% of study cats exhibiting an increase in LMM; averaging an increase of 881 gr/cat. All cats increased fat mass by an average of 437 gr/cat.
Conclusions: Based on the results of this pilot study, we can conclude that the proprietary Fortetropin® muscle powder supplemented to CKD stage II-Ill cats, at 2 gr/day, for 12 weeks appeared to be well tolerated from the gastrointestinal and renal perspectives, and it increased LMM in cats maintained in their home environment and fed a renal-type diet.
References
- PLOS https://doi.org/10.1371/journal.pone.0231306 Published: April 9,2020.
- The Journals of Gerontology: Series A. 2021 Jan:76(1):108-114.
https://doi.org/10.1093/gerona/glaa162 - Canadian Veterinary Journal, 2022 Oct;63(10):1057-1060. PMID: 36185794; PMCID:
PMC9484193. - Frontiers Veterinary Science. 2021 Jul 22;8:680576. doi:10.3389/fvets.2021.680576.
PMID: 34368273; PMCID: PMC8339269 - American College of Veterinary Internal Medicine (ACVIM) Forum, June 9-12, 2021.
Conflict of Interest Disclosure: K. Saker participates on the Advisory Board of MYOS Corp
The Authors would like to thank MYOS® Corporation for the pilot grant funding of this study-Red Bowl Fund, North Carolina Veterinary Medical Foundation, Inc.