Abstract 13571: Association Between Pre-kidney Transplantation Medial Arterial Calcification Andpost-transplant Visit-to-visit Blood Pressure Variability: A Propensity Score Matching Analysis

Abstract

Introduction: Arterial calcification is associated with vascular stiffness, which manifests with visit-to-visit blood pressure variability (VVBPV). Although media arterial calcification (MAC) is significantly associated with poor cardiovascular outcomes in kidney patients, the association in kidney transplant (KT) patients is unknown. Hypothesis: We hypothesize that MAC is associated with VVBPV in long-tern post-KT. Methods: Since MAC, which is detected from mammogram (MG) and determined by linear calcified breast arteries, is exclusively medial, female KT patients with ≥1 MG during pre-KT period were included in this study. VVBPV was examined by average successive variability (ASV), which is the average absolute difference between successive BP measured at 4, 12, 24, 36, and 48 weeks post-KT. After balancing patients with and without MAC by using propensity score matching based on age, diabetes, and obesity status, the association between MAC and systolic and diastolic VVBPV (VVSBPV and VVDBPV) at 48 weeks post-KT was tested by multiple linear regression (Figure1A&1B). Results: Of 51 patients, mean age±SD is 54±12 years, 21 had diabetes, and 21 were obese. Mean duration of follow-up was 47±9 years. Among 20 patients with MAC, mean VVSBPV was 20±14 mmHg; whereas, VVSBPV in non-MG group was 14±8 mmHg (mean difference -6± 3.0, p 0.06, 95%CI -12.03, 0.15). Mean VVDBPV in MG and non-MG groups were 12±5 and 11±5.6 mmHg, respectively (mean difference -1±1.6, p 0.41, 95%CI -4.44, 1.86). Laboratory-related bone and mineral metabolism were not different between both groups. On average, MG group had 8 mmHg higher VVSBPV compared to non-MG group (Coef. 3.62, p 0.02, 95%CI 1.16, 15.34). The MG group remained having higher VVDBPV but the magnitude of the association decreased and no statistical significance (Coef. 0.58, p 0.83, 95%CI -4.58, 5.73). Conclusions: Similar to non-transplant patients, KT recipients with pre-KT MAC had significant higher VVSBPV at the late post-KT.