Poorly concentrated urine is associated with an increased risk of developing chronic kidney disease in apparently healthy cats.

A USG below 1.035 in apparently healthy mature cats significantly increases CKD risk and warrants enhanced renal monitoring.

This 2-year longitudinal retrospective cohort study evaluated 15,027 apparently healthy mature and senior cats to determine whether urine specific gravity (USG) below 1.035 at initial assessment was associated with increased risk of developing presumptive chronic kidney disease (CKD). Cats were stratified by age (mature: 11–15 years; senior: >15 years) and USG (<1.035 or ≥1.035). After exclusion criteria were applied, 504 mature cats with USG <1.035, 1,872 mature cats with USG ≥1.035, 89 senior cats with USG <1.035, and 149 senior cats with USG ≥1.035 were included. CKD diagnosis required either a formal clinician diagnosis or development of creatinine >1.6 mg/dL combined with USG <1.035 and consistent clinical signs, with confounding diagnoses excluded. In mature cats, contingency analysis revealed a statistically significant odds ratio of 3.191 (95% CI, 1.611–6.231) for developing presumptive CKD in those with initial USG <1.035, along with a significantly shorter time to CKD diagnosis. These findings suggest that inadequate urine concentration in mature cats is a meaningful early indicator of subclinical renal disease. Clinicians are encouraged to consider USG <1.035 in otherwise healthy mature cats as a prompt for individualized diagnostic workup and enhanced renal monitoring, even in the absence of azotemia or overt clinical signs, as this may facilitate earlier CKD detection and intervention.

This summary was distilled by AI and may occasionally misinterpret data. Confirm critical details with the primary literature before clinical application.