Five Months. That is what a renal diet is worth in a CKD cat according to new research from IDEXX

New research quantifies something you have long suspected. The renal diet conversation is one of the most important ones you will have and most cats are not having it early enough.

Five months.

That is the average survival difference between cats with early chronic kidney disease who were consistently fed a veterinary therapeutic renal diet and those who were not, according to a new study of more than 1,400 cats published in the Journal of the American Veterinary Medical Association.

Five months does not sound enormous until you think about what five months means to the owner of a thirteen-year-old cat who has had that animal for a decade. Five months is a winter. Five months is the difference between being there for one more summer or not. For clients who are already stretched emotionally and financially by a CKD diagnosis, five months is not a small thing.

And that is before you get to the progression data.

What the study actually found

This was a large retrospective study using real-world medical records from practices across the US and Canada — 1,430 cats diagnosed with early-stage CKD, split between those who received a consistent renal diet within 60 days of diagnosis and those who did not.

The findings were consistent across every early stage of the disease. Cats in Stage 1 CKD who were started on a renal diet had a 45% lower hazard of progressing to a more advanced stage. Their median time to progression was 20 months versus 9 months in untreated cats — more than double. Stage 2 cats with creatinine still within the reference interval showed a 46% lower hazard of progression and progressed a median of 19 months later than their untreated counterparts. Even the sicker Stage 2 cats, those with creatinine already above the reference interval, showed a 41% lower hazard of progression with dietary intervention.

The survival analysis found a 30% reduction in all-cause mortality in treated cats, with a restricted mean survival time of 31 months compared to 26 months in untreated cats over a three-year follow-up.

These are not marginal findings. For a disease that is one of the leading causes of death in cats over five years old — with prevalence estimates as high as 81% in cats aged 15 to 20 — the clinical stakes of this data are significant.

The conversation your clients are not hearing

Here is the uncomfortable part. The study found that only 33% of CKD-diagnosed cats had consistent evidence of renal diet use in their medical records. A third. In a disease where dietary intervention at early stages is now showing 45% reductions in progression hazard, two out of three cats are not on the diet.

Some of that gap is clinical, not every Stage 1 cat gets the dietary recommendation under current IRIS guidelines, which reserve early dietary intervention for cats with elevated FGF23. This study suggests the threshold for that recommendation may need to move earlier. But some of the gap is also adherence. Prior research puts the rate of failed diet transitions at around 42%, because the cat won't eat it, or the owner won't commit to it, or both.

That is the real clinical challenge this data surfaces. It is not just about when to recommend the diet. It is about how to have the conversation in a way that actually lands.

Owners of cats with early CKD are often managing a diagnosis that feels abstract. The creatinine is a little high. The SDMA is creeping. The cat seems fine. The urgency is not obvious from the outside. And then someone asks them to switch the food their cat has eaten happily for ten years to something the cat may refuse, often at a higher cost, for a benefit they cannot see.

What this study gives you is something concrete to put in that moment. Not "the guidelines recommend a renal diet." Not "it may help slow things down." The median time to progression more than doubled in Stage 1 cats on the diet. Five additional months of survival. Numbers that a client can hold onto when they are at the pet store choosing between the prescription food and the food their cat already likes.

The conflict of interest is worth naming

The study authors are affiliated with IDEXX Laboratories, which manufactures SDMA testing and has a commercial interest in early CKD diagnosis. That does not make the findings wrong — the methodology is rigorous, the dataset is large, and the results are consistent with the direction of prior research in this area. But it is worth knowing when you are reading the data, and it is worth noting that independent replication of these findings in an early CKD population would strengthen the evidence base considerably.

What is not in dispute is the direction. Renal diets slow CKD progression in cats. That has been established across multiple studies over multiple decades. What this paper adds is the early-stage data that has historically been limited, and a sample size large enough to produce meaningful hazard ratios across Stage 1 and early Stage 2 populations.

What this means for your practice tomorrow

The cat in your exam room with the mildly elevated SDMA and the owner who thinks everything is basically fine is the patient this data is about. The window for maximum dietary impact is open right now, before azotemia, before clinical signs, before the owner is managing a crisis instead of a chronic condition.

Have the conversation. Show them the numbers. Help them find a food their cat will actually eat. And document the recommendation, because the follow-up conversation in six months will be easier if the foundation is already there.

Five months is worth the awkward appointment.

Source: Journal of the American Veterinary Medical Association, 2026. Authors affiliated with IDEXX Laboratories Inc.