en تخصصي Special پژوهشي Research <span style="font-size:12pt"><span style="line-height:107%"><span new="" roman="" style="font-family:" times="">Chronic kidney disease (CKD) affects 30&ndash;40% of cats over 10 years old, highlighting the need to identify modifiable dietary risk factors. This case-control study (2021&ndash;2023) evaluated pre-morbid diets in 194 client-owned cats (97 CKD cases, 97 controls) from southeastern Iran, excluding those with comorbidities and exclusively outdoor housing. CKD diagnosis was based on IRIS criteria (serum creatinine &ge;1.6 mg/dL, urine specific gravity <1.030/proteinuria). Dietary intake was assessed using validated owner questionnaires, categorizing diets as commercial dry/wet, non-formulated homemade, or veterinary-formulated mixed diets. Cats with CKD had significantly higher creatinine levels (2.1 vs. 1.4 mg/dL, p<0.001), with 65% at IRIS Stage 2. Non-formulated homemade diets (28.9% vs. 16.5% controls; OR=2.1, p=0.04) and commercial wet foods (29.9% vs. 16.5%; OR=2.1, p=0.027) were associated with increased CKD risk, whereas veterinary-formulated mixed diets were protective (10.3% vs. 22.7%; OR=0.4, p=0.02). Subgroup analyses linked non-formulated diets to underweight status (p=0.003) and dry food consumption to obesity (p=0.01). These findings emphasize the critical role of diet formulation quality, particularly phosphorus-protein balance, in mitigating renal stress. Despite the observational design and potential residual confounders limiting causal inference, results support early nutritional counseling, IRIS-aligned diets, and routine screening to prevent CKD in aging cats. Future research should explore biomarker-guided dietary interventions to enhance feline renal health.</span></span></span><br> &nbsp; Chronic kidney disease (CKD), Domestic cats, Veterinary-formulated diets, Dietary risk factors 25 33 http://injvr.com/browse.php?a_code=A-10-71-1&slc_lang=en&sid=1 A. Jamshidi amirjamshididvm@gmail.com 10031947532846001404 10031947532846001404 No Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Zabol, Zabol, Iran B. Akhtardanesh akhtardanesh@uk.ac.ir 10031947532846001405 10031947532846001405 Yes Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahid Bahonar University of Kerman, Kerman, Iran