Use of a veterinary therapeutic renal diet in cats with early chronic kidney disease is associated with slower disease progression and improved survival

Objective: To determine disease progression and survival duration in cats diagnosed with early-stage chronic kidney disease (CKD) continuously treated with a veterinary therapeutic renal diet versus those untreated at diagnosis. Methods: This retrospective study utilized a commercial database of medical records from veterinary practices located in Canada and the US. Cats born between January 1, 2010, and December 31, 2014, diagnosed with early-stage CKD were randomly selected. Records were reviewed to determine the date of diagnosis and whether treatment with a therapeutic renal diet was initiated. Progression of CKD and survival duration were evaluated with longitudinal targeted maximum likelihood estimation modeling. Results: Of 1,430 cats with early CKD, 839 received a veterinary therapeutic renal diet and 591 did not. Dietary therapy was associated with reduced risk of progression. Treated CKD Stage 1 cats had a 45% lower hazard of progression (hazard ratio [HR], 0.55; 95% CI, 0.52 to 0.58). Treated CKD Stage 2 cats that had creatinine within and above the reference intervals had 46% (HR, 0.54; 95% CI, 0.50 to 0.58) and 41% (HR, 0.59; 95% CI, 0.56 to 0.62) lower hazards of progression, respectively. Cats treated with a therapeutic renal diet had a longer survival over 3 years: restricted mean survival time was 31.0 versus 26.0 months in untreated cats. Conclusions: Use of a veterinary therapeutic renal diet in cats with early CKD slows disease progression and improves survival. Clinical Relevance: Early diagnosis and intervention with a therapeutic renal diet may optimize long-term outcomes in cats with CKD.