Kidney Week

Abstract: SA-PO361

Epimeric Vitamin D Is Not Associated with Arterial Stiffness in Patients with Advanced CKD

Session Information

• Hypertension, CVD, and the Kidneys: Clinical Research
  October 26, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Hypertension and CVD

• 1602 Hypertension and CVD: Clinical

Authors

• Campos, Monique Opuszcka, Indiana University School of Medicine, Indianapolis, Indiana, United States

Monique Opuszcka Campos, PhD

• Arroyo, Eliott, Wake Forest University, Winston-Salem, North Carolina, United States

Eliott Arroyo, PhD

• Hiemstra, Thomas, University of Cambridge School of Clinical Medicine, Cambridge, United Kingdom

Thomas Hiemstra, MD, PhD

• Narayanan, Gayatri, Indiana University School of Medicine, Indianapolis, Indiana, United States

Gayatri Narayanan, MS

• Burney, Heather, Indiana University School of Medicine, Indianapolis, Indiana, United States

Heather Burney, MS

• Lim, Kenneth, Indiana University School of Medicine, Indianapolis, Indiana, United States

Kenneth Lim, MD, PhD, FASN

Background

25-hydroxyvitamin D3 (25-(OH)D3) has the capacity for C-3 epimerization, resulting in the production of 3-epi-25(OH)D3. 3-epi-25(OH)D3 comprises up to ~54% of total 25(OH)D concentrations and therefore could significantly influence end-organ health. We recently demonstrated that 3-epi-25(OH)D3 levels are reduced in patients with advanced CKD and are associated with impaired cardiovascular (CV) functional capacity. However, its role in regulating vascular health in CKD is still largely unstudied. Herein, we investigated the association of serum 3-epi25(OH)D3 with arterial stiffness in patients with advanced CKD.

Methods

We conducted a cross-sectional study of baseline data from 270 participants from the Coventry-Cambridge Vascular Cohort that recruited patients with stage 5 CKD on the transplant list. All patients underwent arterial applanation tonometry to assess arterial stiffness (pulse wave velocity (PWV) and augmentation index at 75 bpm (AI75)). Serum 3-epi-25(OH)D3 was analyzed by liquid chromatography-tandem mass spectrometry. Participants were stratified into 3-epi-25(OH)D3 quartiles, with one-way ANOVA comparing differences and associations assessed using multiple linear regression.

Results

3-epi-25(OH)D3 levels across quartiles were: < 0.30 ng/mL(n=64); 0.30-0.45 ng/mL(n=71); 0.46-0.73ng/mL(n=68); >0.73ng/mL(n=67). 3-epi-25(OH)D3 quartiles were well matched for age, gender, and BMI (p>0.05). There was a difference in race (<0.001) and dialysis status (p=0.016) among quartiles. The estimated glomerular filtration rate (eGFR) did not significantly differ among 3-epi-25(OH)D3 quartiles (Q1: 8.0 [80,101], Q4: 8.0 [5.3,12.0] ml/min per 1.73 m², median [IQR]) p>0.05). There were no differences among quartiles for either PWV (Q1: 7.9 [7.0,9.6], Q4: 7.8 [6.6,9.0] m/s, median [IQR]) p>0.05) and augmentation index (Q1: 20.5 ± 13.7; Q4: 20.4 ± 13.4 %, p>0.05). Multiple linear regression modeling demonstrated that 3-epi-25(OH)D3 was not associated with either PWV and AI75 after adjustment for race and dialysis status (p=0.72).

Conclusion

Our study demonstrates that epimeric vitamin D levels are not associated with modulating arterial stiffness in patients with advanced CKD. Therefore, its relationship with cardiovascular functional capacity in CKD may be mediated by non-vascular targets.

Funding

• Private Foundation Support