Resident The Ohio State University Veterinary Medical Center Columbus, OH, United States
Abstract:
Background: Chronic kidney disease - mineral and bone disorder (CKD-MBD) is characterized in part by vitamin D dysregulation, yet comprehensive vitamin D metabolite profiles have yet to be elucidated in cats with CKD. Evidence-based recommendations for vitamin D supplementation are lacking. Hypothesis/
Objectives: The primary objective was to investigate comprehensive vitamin D metabolite profiles (25-hydroxyvitamin D3 [25D], 1,25-dihydroxyvitamin D3 [1,25D], D, 24,25-dihydroxyvitamin D3 [24,25D], and 3-epi-25-hydroxyvitamin D3 [3-epi-25D]) in cats with CKD compared to healthy controls. We hypothesized that all vitamin D metabolites would be lower in cats with CKD compared to healthy cats and that vitamin D metabolites would be negatively correlated with serum creatinine. Animals: Client-owned cats with naturally occurring CKD (n=42) and healthy cats from a research colony (n=12) were included.
Methods: Retrospective cohort study. All serum vitamin D metabolites were measured via liquid chromatography-mass spectrometry (LC-MS/MS). Data were analyzed using a Mann-Whitney U test and Spearman correlation.
Results: Median (range) concentrations for 25D, 1,25D, 24,25D, and 3-epi-25D in cats with CKD were 30.0 ng/mL (12.2-68.8 ng/mL), 136.8 pg/mL (38.6-367.8 pg/mL), 10.9 ng/mL (2.7-32.5 ng/mL), and 9.1 ng/mL (2.2-30.4 ng/mL), respectively. Compared to healthy cats, all vitamin D metabolites were significantly higher in cats with CKD (p < 0.05; Table 1). A weak positive correlation was found between creatinine and 25D, 24,25D, and 3-epi-25D (r: 0.28-0.32; p<.05). Conclusions and clinical relevance: These results do not mirror what has been demonstrated in people or dogs with CKD-MBD. This study does not support the utility of calcitriol supplementation in cats with CKD.
