Long-Term Changes in Blood Pressure After Pediatric Kidney Transplantation

Background: Hypertension presents high prevalence rates following kidney transplantation (Tx). The aims of the present study were to investigate the prevalence and possible risk factors for hypertension and blood pressure (BP) control over time after pediatric kidney Tx, as well as to assess possible effects of hypertension on graft survival.

Methods: We reviewed the medical records of all pediatric kidney recipients followed up in our pediatric nephrology department. Hypertension was defined as systolic and/or diastolic BP greater than the 95th percentile for age and sex, or as being on antihypertensive medication. BP control was defined as normotension while on antihypertensive medication.

Results: The study population included 74 pediatric kidney recipients (median age 11 years). The prevalence of hypertension was found 77% before Tx, 82.4%, 71.7%, and 61% at 1, 5, and 10 years after Tx, respectively. Deceased donor Tx and pre-transplant hypertension on antihypertensive medication were significant risk factors for hypertension after kidney Tx over the follow-up period. BP control among patients on antihypertensive treatment was 16.7% before Tx, 43.8%, 66.7%, and 42.9% at 1, 5, and 10 years post-Tx, respectively. Hypertensive patients at 10 years post-Tx had 8.079 times higher hazard of graft loss compared to normotensives (95% CI 1.561-41.807, P < 0.05).

Conclusions: Hypertension remains a frequent complication in pediatric kidney recipients even years after kidney Tx. BP control by antihypertensive treatment is unsatisfactory in about half of the patients. The adverse effects of hypertension on graft survival may appear in the long-term.