How I Treat... Nutrition of the Geriatric Cat With Chronic Kidney Disease

Of all the CKD treatments, dietary modification has the most positive long term effect on outcome.

HYDRATION
Unrestricted access to water is essential in CKD patients to compensate for solute diuresis. Older cats do not sense thirst well and need encouragement to take in enough fluids to prevent dehydration. Provide easy access to water – some cats like running water. Adding water to the food may be beneficial. Some cats benefit from intermittent IV or SQ crystalloid fluids¹.

PROTEIN
While dietary protein restriction has long been advocated for the management of CKD, the optimal amount of protein for patients with kidney disease is not really known as protein restricted diets are also phosphorus restricted and the effects of the two parameters are difficult to separate.

Controlled restriction of non-essential protein will reduce the accumulation of the nitrogenous waste products which contribute to the uraemic syndrome, and may also decrease acidosis. In one study cats in IRIS stage 2 or 3 fed a diet for renal disease showed decreased serum urea nitrogen and increased blood bicarbonate, but there was no difference in serum creatinine, potassium, calcium, or parathyroid hormone concentration or urine protein to creatinine ratio. The cats on the diet for renal disease showed fewer uraemic episodes and less renal disease associated deaths². Lower protein diets have been thought to slow the rate of progression of renal disease, although this concept is very controversial. Higher protein diets do not appear to increase the risk of developing kidney disease. Recommendations for protein restriction in cases where overt signs of CKD are present are 28 to 35% dry matter basis³ (Forrester, et al 2010). While there is no evidence supporting dietary modification in IRIS stage¹, introducing a diet change early improves diet acceptance. Over 90% of cats with CKD accepted renal diets when a very gradual transition was used².