Blood Pressure Goals and Outcomes in Kidney Transplant Recipients in an Analysis of the Collaborative Transplant Study

Abstract

Introduction

Hypertension is an independent risk factor for cardiovascular disease, the leading cause of death in kidney transplant recipients. However, optimal blood pressure targets posttransplant remain uncertain. We investigated the impact of different American College of Cardiology and the American Heart Association (ACC/AHA) blood pressure categories on graft survival and patient mortality, and analyzed subgroup-specific effects.

Methods

This large-scale retrospective study included 1-year blood pressure data from 62,556 kidney transplant recipients across 209 centers in 39 countries, using the collaborative transplant study (CTS) database. Primary outcomes were death-censored graft failure and patient mortality during first 6 years posttransplantation. Multivariable Cox regression analysis controlled for multiple immunological and nonimmunological confounders.

Results

At 1 year posttransplant, 77% of kidney transplant recipients had hypertension. We did not find a significant difference in death-censored graft failure and patient mortality between patients with normal blood pressure (< 120/< 80 mm Hg) and those with elevated blood pressure (120–129/< 80 mm Hg). Hypertension stages 1 (130–139/80–89 mm Hg) and 2 (≥ 140/≥ 90 mm Hg) were associated with an 11% and 55% increased risk of death-censored graft failure, respectively. Patient mortality was only significantly increased in those with hypertension stage 2. Kidney transplant recipients with hypertension stage 2 continued to have an increased risk of graft failure, even when they achieved normal blood pressure in the second year posttransplant. Certain subgroups of patients were at particularly high risk of detrimental effects of high blood pressure.

Conclusion

This study highlights the negative impact of hypertension early after kidney transplantation and emphasizes the importance of effective treatment to improve long-term graft and patient survival.