Smart litter box monitoring identifies behavioral patterns associated with feline CKD

Chronic kidney disease (CKD) is common in older cats and is a leading cause of illness and death in the species. Early disease can be difficult for owners to recognize because changes in a cat's behavior may be subtle or develop gradually. A new retrospective study suggests that continuous monitoring of litter box behavior could provide another source of information for identifying patterns associated with CKD.

Researchers from Nestlé Purina Research and The Ohio State University's College of Veterinary Medicine analyzed data collected by a smart litter box monitor equipped with load-cell sensors. The device records elimination events and measures characteristics including frequency, duration, urine weight and post-elimination covering behavior. The findings were published in Animals.¹

A retrospective look at 136 cats

The study included data collected between January 2023 and September 2025 from 136 cats. The training group consisted of 13 cats with confirmed CKD and 72 cats with no known conditions. A separate validation group included 7 cats with reported CKD and 44 cats with no known conditions.¹

Data were collected for between 2 weeks and 2 years per cat, with a median of 6 weeks. Investigators used mixed-effects modeling to compare 24 behavioral features between the groups and then trained a machine-learning model, CatBoost, to classify cats based on their elimination patterns.¹

Cats with CKD displayed several differences from cats with no known conditions. They had nearly twice the urination frequency, produced substantially more urine by weight and spent less time covering waste after elimination. Their covering behavior also was less intense. Urination itself took longer, although total time spent in the litter box during an elimination event was shorter overall.¹

The researchers observed this behavioral profile among cats representing different stages of CKD, including cats with early-stage disease. Several of the differences identified in the study were also apparent among cats classified as IRIS stage 1 or 2, suggesting that some behavioral changes may be detectable before CKD becomes more advanced.¹

The study does not establish, however, that the monitor can detect CKD before clinical signs or a veterinary diagnosis. The researchers analyzed behavioral data from cats already known or reported to have CKD rather than prospectively following healthy cats to determine whether the monitor could predict a subsequent diagnosis.

A tool to complement veterinary diagnostics

The model distinguished cats with CKD from those without known conditions, with weighted F1-scores of 92.7% in the training group and 89.9% in the separate validation group.1 The model did not identify every cat with CKD, however, with a CKD recall of 57.1% in the validation group.¹

Two cats in the validation group whose owners did not report a CKD diagnosis were nevertheless classified by the model as having patterns consistent with the disease. The researchers did not have follow-up diagnostic testing to determine whether either cat actually had CKD, so the finding does not establish that the monitor detected disease before diagnosis.¹

"Chronic kidney disease is common in older cats, but it can be challenging for pet owners to recognize early because changes may be gradual and easy to miss in day-to-day life," said Ragen McGowan, PhD, of Nestlé Purina PetCare Global Research & Development and a co-author of the study.² "By monitoring elimination behavior and body weight patterns passively in the home, we can identify trends that may signal a need for veterinary evaluation and diagnostic testing. This type of continuous, objective data has the potential to complement routine care—not replace it—by prompting pet owners to have earlier conversations with their veterinarians and follow-up when a cat's pattern changes."²

The findings may be most applicable to indoor cats with consistent access to the monitored litter box. The authors emphasized that the technology should be viewed as a complementary screening tool rather than a replacement for veterinary examination, bloodwork, urinalysis or other diagnostic testing.¹

For veterinary teams, the study highlights the potential value of in-home monitoring tools that can provide objective behavioral data between veterinary visits. Changes in litter box habits may not be specific to CKD, but tracking those changes over time could give owners and veterinarians another reason to investigate when a cat's routine begins to shift.

References

1. Langenfeld-McCoy N, Snow L, Gordon H, et al. Enhancing detection of feline chronic kidney disease through smart litter box monitoring. Animals. 2026;16(9):1319. doi:10.3390/ani16091319.
2. Feline elimination patterns linked to kidney disease demonstrated through smart litter box monitor. Purina Institute. Published August 31, 2026. https://newscenter.purina.com/2026-08-31-Feline-Elimination-Patterns-Linked-to-Kidney-Disease-Demonstrated-Through-Smart-Litter-Box-Monitor