Page 758 - Small Animal Clinical Nutrition 5th Edition

786 Small Animal Clinical Nutrition

VetBooks.ir Box 37-3. Summary of Studies Evaluating Effects of Veterinary Therapeutic Renal Foods on
Survival in Dogs and Cats with Naturally Occurring Chronic Kidney Disease.

Numerous studies have evaluated effects of nutritional manage- the end of the study, 33% of dogs in the renal food group had
ment of chronic kidney disease (CKD) in dogs and cats. Most were developed uremic crises vs. 65% of dogs in the control group. Time
conducted using the remnant kidney model. Although we have to onset of uremic crises was significantly longer in the renal food
learned valuable information from these studies, their findings may group (615 days) compared with the control group (252 days).
not be directly transferable to patients with naturally occurring dis- Feeding the renal food was associated with decreased progression
ease.Three clinical studies evaluated the effects of commercial vet- of kidney disease and significantly prolonged median survival time
erinary therapeutic renal foods on survival and quality of life in cats (594 days) vs. the control group (188 days). As described else-
and dogs with CKD. Those studies are summarized below. where, feeding the renal food was associated with significantly
improved health-related quality of life. Results of this study provide
STUDY 1 Grade I evidence for using this commercial veterinary therapeutic
Fifty cats with naturally occurring stable CKD were evaluated in a renal food to decrease uremic episodes, delay onset of uremia and
prospective study of the effects of feeding a dry or moist veterinary progression of kidney disease, increase survival time and improve
a
therapeutic renal food compared with a maintenance food. The quality of life in dogs with CKD.
renal food contained 22 to 24% dry matter (DM) protein and 0.27
to 0.42% DM phosphorus whereas the maintenance food con- STUDY 3
tained 48% DM protein and 1.9% DM phosphorus. Twenty-nine Forty-five cats with stable CKD (serum creatinine values of 2.1 to
cats accepted the renal food and were assigned to the renal food 4.5 mg/dl) were evaluated in a double-blinded, randomized, con-
group, whereas compliance (due to limited intake by the cats or trolled prospective study to determine effects of feeding a commer-
c
owner resistance to diet change) was not achieved in the remain- cial dry and/or moist veterinary therapeutic renal food compared
ing 21 cats, which were assigned to the maintenance food group. with a control food that was similar to a typical adult maintenance
Cats in the maintenance food group were fed commercial mainte- cat food.The renal food contained 28 to 29% DM protein, 0.5% DM
nance cat foods with varying amounts of fresh meat or fish. In all phosphorus, and 0.2 to 0.6% DM omega-3 fatty acids, whereas the
cases, the dietary regimens were considered appropriate for main- control food contained 46 to 48% DM protein, 0.9 to 1% DM phos-
tenance. At diagnosis, both groups of cats were matched in terms phorus and 0.2% DM omega-3 fatty acids. Cats were fed a combi-
of age, body weight, plasma creatinine, phosphate, potassium and nation diet (half renal food, half control food) for six weeks before
parathyroid hormone (PTH) concentrations, packed cell volume and random assignment to treatment groups; this was done to gradual-
urine specific gravity. Cats in the renal food group received their ly transition cats to a new food. At the end of the two-year study
assigned food for an average of 86.6% of their survival time. there were 23 cats in the control group and 22 cats in the renal
Feeding the renal food was associated with a reduction in plasma food group. Dietary compliance (defined as receiving >85% of daily
phosphorus and urea nitrogen concentrations and prevented the caloric requirement from the assigned food) was excellent through-
increase in plasma PTH concentrations that occurred in the main- out the study; 91% of cats continued eating their assigned food.
tenance food group. Median survival time was significantly longer Four cats (two in each group) stopped eating due to nonrenal dis-
in the renal food group (633 days) compared with the maintenance eases. A significantly greater percentage of cats in the control
food group (264 days). Results of this study provide Grade III evi- group had uremic episodes (26%) compared with the renal food
dence for using this commercial veterinary therapeutic renal food to group (0%). There was significant reduction in deaths due to CKD
control secondary renal hyperparathyroidism and prolong survival in the renal food group; none of the cats receiving the renal food
time in cats with naturally occurring CKD. died during the study whereas 22% of cats in the control group
died. Results of this study provide Grade I evidence for using this
STUDY 2 commercial veterinary therapeutic renal food to decrease occur-
Thirty-eight dogs with stable CKD (serum creatinine values between rence of uremic episodes and mortality in cats with CKD.
2 and 8 mg/dl) were evaluated in a double-blinded, randomized,
controlled prospective study to determine effects of feeding a com- ENDNOTES
b
mercial dry veterinary therapeutic renal food compared with a a. Waltham Veterinary Diet, Whiskas Low Phosphorus Low Protein.
control food formulated to represent the nutrient content of the 10 Masterfoods, Bruck, Austria.
most popular selling grocery brand maintenance foods. The renal b. Prescription Diet k/d Canine. Hill’s Pet Nutrition, Inc., Topeka, KS,
food contained 14% DM protein, 0.28% DM phosphorus and 1.6% USA.
DM omega-3 fatty acids, whereas the control food contained 25% c. Prescription Diet k/d Feline. Hill’s Pet Nutrition, Inc., Topeka, KS,
DM protein, 1% DM phosphorus and 0.22% DM omega-3 fatty USA.
acids. At baseline, clinical and laboratory findings were similar
between groups. At the end of the two-year study there were 17 The Bibliography for Box 37-3 can be found at
dogs in the control group and 21 dogs in the renal food group. By www.markmorris.org.