Association Between Systolic Blood Pressure Time in Target Range and Graft Outcomes in Kidney Transplant Recipients

초록

Purpose: Time in target range (TTR) for BP reflects the consistency of BP control and may better predict outcomes than single measurements. We examined the association between SBP-TTR and graft outcomes in kidney transplant recipients (KTRs). Methods: We conducted a prospective observational cohort study including 4,559 KTRs from the nationwide Korean Organ Transplantation Registry (main) and 828 from the multicenter KoreaN Cohort Study for Outcome in Patients With Kidney Transplantation (replication). SBP-TTR within 110-130 mmHg was calculated using linear interpolation of office BP at 6, 12, and 24 months post-transplantation (12, 24, and 36 months in the replication cohort). The primary outcome was a composite of death-censored graft loss or ≥50% decline in eGFR. Results: Over a median follow-up of 4 years, each 1-SD increase in SBP-TTR was associated with a 20% lower risk of the composite outcome (aHR, 0.80; 95% CI, 0.71-0.91). Compared with the 0% SBP-TTR group, the 1-50%, 51-99%, and 100% SBP-TTR groups had progressively lower risks (aHRs [95% CI]: 0.69 [0.50-0.95], 0.63 [0.46-0.87], and 0.47 [0.31-0.71], respectively). Stronger associations were observed among recipients of deceased donor kidneys and those with older or female donors or a higher baseline SBP. The replication cohort showed similar associations. Conclusions: A higher SBP-TTR within 110-130 mmHg was associated with a lower risk of graft dysfunction, with consistent effects across most subgroups and more pronounced benefits in high-risk populations. Sustained SBP control may be a key therapeutic target in KTRs, warranting interventional studies.