Abstract P099: Pulse Pressure And Long-term Post-kidney Transplant Systolic Hypertension Among Different Age

Abstract

Introduction: Wide pulse pressure (PP) is common in elderly and associated with poor cardiovascular outcomes. Association between PP and long-term hypertension (HTN) in kidney transplant recipients (KTR) among different age groups is unclear. Hypothesis: We hypothesize that PP at early post-kidney transplant (KT) predicts different long-term post-KT HTN among different age groups. Methods: This is a retrospective cohort study of consecutive KT recipient in a single center. With age categorized into < and ≥ 50 years old, association between PP at 4 and 12 weeks post-KT (when a baseline kidney allograft function is generally established) and post-KT systolic and diastolic HTN (SHTN and DHTN) at a 48-week post-KT defined by SBP and DBP ≥ 130 and 80 mmHg, respectively were examined by using multiple logistic regression. Results: Of all 105 KTR, 40 and 65 patients were <50 and 65 years old, respectively. Mean age±SD was 54±12 years with a median follow-up of 47.71 weeks. At a 4-week post-KT, mean PP was 54±13 mmHg with a mean difference young - old ±SE of -7±3 (p 0.011; 95%CI -11.55, -1.53). Mean PP at a 12-week post-KT was 56±16 mmHg and a mean difference±SE of -8±3 mmHg (p 0.018; 95%CI -13.95, -1.35). At 48-week post-KT, 50% of the young had SHTN 66% of the old had SHTN; whereas, 58% and 38% of the corresponding groups had DHTN. Mean SBP of the young and old groups were 129±16 and 135±16 mmHg, respectively (mean difference -6±3; p 0.076; 95%CI -12.66, 0.63). Mean DBP of the corresponding groups were 80±12 and 75± 10 with a mean difference 5±2; p 0.036; 95%CI 0.332, 9.394). After adjusted for pre-KT BMI, type of KT, and induction immunosuppression, every 1 mmHg increase in PP at the 4-week post-KT was associated with 6% greater the odds of developing SHTN at 48-week post-KT among the older age group (OR 1.06; p 0.041, 95%CI 1.002, 1.117); whereas, the risk was 2% increase in younger group (OR 1.02; p 0.400; 95%CI 0.969, 1.082). The association between PP at the 12-week post-KT and SHTN at 48-week post-KT were in the same direction, but it was attenuated (5%) in the older and strengthen the younger (7%) (OR old 1.048; p 0.033; 95%CI 1.004, 1.095 and OR young 1.087; p 0.050; 95%CI 1.000, 1.1801). There were no association between PP at 4- and 12-week post-KT and DHTN at 48-week post-KT. Conclusion: Higher early post-KT PP was associated with increased risk of long-term post-KT SHTN, but not DHTN. However, the magnitude of the association was greater among the older KTR at early post-KT, but higher in the younger at later post-KT period. Mechanism of increased PP and outcomes such as post-KT HTN in KTR needs to be further elucidated.