Hypertension after kidney transplantation

Hypertension increases the cardiovascular risk in kidney transplant recipients (KTRs). In chapter 2 we found that hypertension was highly prevalent in adult (77.2%), paediatric (62.7%) and young adult (86.4%) KTRs. Transition from the paediatric to adult care did not affect hypertension and there were large variations in hypertension management policies between Dutch centres as shown in chapter 3. The randomised-crossover clinical trial in chapter 4 reports that sodium restriction in stable KTRs on RAAS inhibition is feasible, decreases systolic and diastolic blood pressure (BP) but only modestly effects urinary albumin excretion. In chapter 5, we studied nocturnal BP dipping profiles (as additional CV risk factor) in KTRs using the prolonged release once-daily tacrolimus compared to the twice-daily formulation. No difference was found. In chapter 6, we hypothesised that sympathetic nerves regrow after transplantation and can be visualised using ¹²³I-mIBG scintigraphy. We demonstrated that ¹²³I-mIBG uptake at 15min, but not at 4h p.i, significantly correlated with time after transplantation, suggesting functional reinnervation in renal allografts over time, independent of allograft function. In chapter 7, we hypothesised that changes in sympathetic nerve activity assessed by renal ¹²³I-mIBG scintigraphy, relate to changes in BP and catecholamines after catheter-based renal sympathetic denervation (RDN). No changes in ¹²³I-mIBG parameters were found, suggesting that incomplete denervation is a possible explanation for the lack of RDN efficacy. Finally, chapter 8 is a case report of RDN of the native kidneys in a single KTR, who had a sustained BP lowering six months after RDN.