Intensive blood pressure control is associated with improved patient and graft survival after renal transplantation

Impact of Blood Pressure on Allograft Function and Survival in Kidney Transplant Recipients

The optimal target blood pressure for kidney transplant (KT) patients remains unclear. We included 808 KT patients from the KNOW-KT as a discovery set, and 1,294 KT patients from the KOTRY as a validation set. The main exposures were baseline systolic blood pressure (SBP) at 1 year after KT and time-varying SBP. Patients were classified into five groups: SBP <110; 110-119; 120-129; 130-139; and ≥140 mmHg. SBP trajectories were classified into decreasing, stable, and increasing groups. Primary outcome was composite kidney outcome of ≥50% decrease in eGFR or death-censored graft loss. Compared with the 110-119 mmHg group, both the lowest (adjusted hazard ratio [aHR], 2.43) and the highest SBP (aHR, 2.25) were associated with a higher risk of composite kidney outcome. In time-varying model, also the lowest (aHR, 3.02) and the highest SBP (aHR, 3.60) were associated with a higher risk. In the trajectory model, an increasing SBP trajectory was associated with a higher risk than a stable SBP trajectory (aHR, 2.26). This associations were consistent in the validation set. In conclusion, SBP ≥140 mmHg and an increasing SBP trajectory were associated with a higher risk of allograft dysfunction and failure in KT patients.

A holistic review of sodium intake in kidney transplant patients: More questions than answers

Kidney transplantation (KT) is the best treatment option for end-stage kidney disease (ESKD). Acute rejection rates have decreased drastically in recent years but chronic kidney allograft disease (CKAD) is still an important cause of allograft failure and return to dialysis. Thus, there is unmet need to identify and reverse the cause of CKAD. Additionally, cardiovascular events after KT are still leading causes of morbidity and mortality. One overlooked potential contributor to CKAD and adverse cardiovascular events is increased sodium/salt intake in kidney transplant recipients (KTRs). In general population, the adverse effects of high sodium intake are well known but in KTRs, there is a paucity of evidence despite decades of experience with KT. Limited research showed that sodium intake is high in most KTRs. Moreover, excess sodium intake is associated with elevated blood pressure and albuminuria in some studies involving KTRs. There is also experimental evidence suggesting that increased sodium intake is associated with histologic graft damage. Critical knowledge gaps still remain, including the exact amount of sodium restriction needed in KTRs to optimize outcomes and allograft survival. Additionally, best methods to measure sodium intake and practices to follow-up are not clarified in KTRs. To meet these deficits, prospective long term studies are warranted in KTRs. Moreover, preventive measures must be determined and implemented both at individual and societal levels to achieve sodium restriction in KTRs.

The impact of diabetes and hypertension on renal allograft survival- A single center study

Background

To determine the impact of pre-transplant diabetes mellitus (DM) and post-transplant hypertension (HT) at 1 year on renal allograft survival in all adult first kidney-only (FKO) transplant recipients at a single transplant center in Johannesburg, South Africa.

Materials and methods

A retrospective review was conducted of all adult FKO transplant procedures at the Charlotte Maxeke Johannesburg Academic Hospital transplant unit between 1966 and 2013.

Results

During the stipulated timeframe, 1685 adult FKO transplant procedures were performed. Of these, 84.1% were from deceased donors (n = 1413/1685). The prevalence of pre-transplant DM transplant recipients with no missing or incomplete records was 6.5% (n = 107/1625). Of the total cohort of 1685 adult FKO transplant recipients, 63.6% of those with no missing data survived to 1 year (n = 1072/1685). The prevalence of HT at 1-year post-transplant was 53.6% (n = 503/1072). HT at 1-year post-transplant, even after adjusted survival analysis, proved a significant risk factor for renal allograft loss (hazard ratio, 1.63; 95% confidence interval, 1.37-1.94) (p < 0.0001). Similarly, after adjusted survival analysis, the risk of renal allograft loss within the pre-transplant DM group was significantly higher (p = 0.043; hazard ratio, 1.26; 95% confidence interval, 1.01-1.58).

Conclusions

This study identified pre-transplantation diabetes mellitus and post-transplantation HT as significant risk factors for graft loss within the population assessed in this region of the world. These factors could potentially be used as independent predictors of renal graft survival.

Uncontrolled hypertension is associated with increased risk of graft failure in kidney transplant recipients: a nationwide population-based study

Backgroud

Hypertension is highly prevalent in patients with kidney transplantation caused by transplantation-related immunologic or non-immunologic risk factors. However, whether a strict definition of hypertension (≥130/80 mmHg) and subdivided blood pressure (BP) groups are associated with an increased risk of graft failure after kidney transplantation using a nationwide large cohort study are still unknown.

Methods

Using Korean National Health Insurance Service data, we included 14,249 patients who underwent kidney transplantation from 2002 to 2016. Patients were categorized into five BP groups according to the 2021 Kidney Disease: Improving Global Outcomes practice guidelines for BP management: normal BP (<120/80 mmHg), elevated BP (120-129/ < 80 mmHg), incident hypertension (≥130/80 mmHg), and controlled or uncontrolled hypertension with anti-hypertensive medications.

Results

The primary outcome was graft failure, which occurred in 1934 (13.6%) participants during the 6-year follow-up. After adjusting for covariates, hypertension was associated with a higher risk of graft failure [Adjusted hazard ratio (AHR), 1.70; 95% confidence interval (CI), 1.48-1.96)] than no-hypertension. The AHR for graft failure was the highest in patients with uncontrolled hypertension (AHR, 2.13; 95% CI, 1.80-2.52). The risk of graft failure had a linear relationship with systolic and diastolic BP, and pulse pressure.

Conclusions

In this nationwide population-based study, hypertension ≥130/80 mmHg based on the 2021 KDIGO BP guidelines in kidney transplantion recipients, and elevated systolic and diastolic BP, and pulse pressure were associated with the risk of developing graft failure in kidney transplant recipients.

Impact of Blood Pressure Control on Graft Survival in Kidney Transplant Recipients

BACKGROUND

Cardiovascular disease is the primary driver of morbidity and mortality in kidney transplant recipients. Hypertension is an important risk factor for development of cardiovascular disease in this population. Despite its important role in post-transplant outcomes, the blood pressure goals for kidney transplant recipients remain elusive. Current guidelines are based on observational data or data extrapolated from the chronic kidney disease population.

METHODS

We followed 5-year blood pressure control of 378 kidney-alone transplant recipients at a single center and evaluated patient survival, graft survival, proteinuria, and rate of decline of kidney graft function.

RESULTS

We found that a mean systolic blood pressure (BP) of 121 to 130 mm Hg was associated with better graft survival, slower decline of kidney allograft function, and lower degree of proteinuria when compared with a mean systolic BP ≤120 or >130 mm Hg.

CONCLUSION

This study provides evidence for strict blood pressure control, systolic BP between 121 and 130 mm Hg, and also cautions against intensive control of systolic BP <120 mm Hg in kidney transplant recipients.

Follow-Up of Blood Pressure, Arterial Stiffness, and GFR in Pediatric Kidney Transplant Recipients

Pediatric renal transplant recipients (RTx) were studied for longitudinal changes in blood pressure (BP), arterial stiffness by pulse wave velocity (PWV), and graft function.

Patients and Methods: 52 RTx patients (22 males) were included; office BP (OBP) and 24 h BP monitoring (ABPM) as well as PWV were assessed together with glycemic and lipid parameters and glomerular filtration rate (GFR) at 2.4[1.0–4.7] (T₁) and 9.3[6.3–11.8] years (T₂) after transplantation (median [range]).

Results: Hypertension was present in 67 and 75% of patients at T₁ and T₂, respectively. Controlled hypertension was documented in 37 and 44% by OBP and 40 and 43% by ABPM. Nocturnal hypertension was present in 35 and 30% at T₁ and T₂; 24 and 32% of the patients had masked hypertension, while white coat hypertension was present in 16 and 21% at T₁ and T₂, respectively. Blood pressure by ABPM correlated significantly with GFR and PWV at T₂, while PWV also correlated significantly with T₂ cholesterol levels. Patients with uncontrolled hypertension by ABPM had a significant decrease in GFR, although not significant with OBP. Anemia and increased HOMAi were present in ~20% of patients at T₁ and T₂.

Conclusion: Pediatric RTx patients harbor risk factors that may affect their cardiovascular health. While we were unable to predict the evolution of renal function based on PWV and ABPM at T₁, these risk factors correlated closely with GFR at follow-up suggesting that control of hypertension may have an impact on the evolution of GFR.

Post-Transplant Cardiovascular Disease

Cardiovascular disease remains a leading cause of death and morbidity in kidney transplant recipients and a common reason for post-transplant hospitalization. Several traditional and nontraditional cardiovascular risk factors exist, and many of them present pretransplant and worsened, in part, due to the addition of immunosuppression post-transplant. We discuss optimal strategies for identification and treatment of these risk factors, including the emerging role of sodium-glucose cotransporter 2 inhibitors in post-transplant diabetes and cardiovascular disease. We present common types of cardiovascular disease observed after kidney transplant, including coronary artery disease, heart failure, pulmonary hypertension, arrhythmia, and valvular disease. We also discuss screening, treatment, and prevention of post-transplant cardiac disease. We highlight areas of future research, including the need for goals and best medications for risk factors, the role of biomarkers, and the role of screening and intervention.

Treatment of Hypertension Because of Immunosuppressive Therapy After Solid Organ Transplantation-Pharmacological Approach

ABSTRACT

Solid organs transplantation procedures have been performed for more than half a century. Growing knowledge of immune response and development of new immunosuppressive regimens guarantee more and more successful outcomes. However, many of the applied drugs lead to cardiovascular complications, the most frequent of which is hypertension. This article describes epidemiology, pathogenetic mechanisms, and treatment of hypertension induced by immunosuppressive medication. The main impact is focused on drugs belonging to the following groups: calcineurin inhibitors, the inhibitors of the mammalian target of rapamycin, and glucocorticosteroids. We analyze the mechanism of action of the main hypertensive drugs and their influence on the reversing hypertonic action of the immunosuppressive agents. In the absence of current guidelines addressing this problem, this article is an attempt to fill the gap, helping clinicians to choose proper medication.

Promoting cardiovascular health post-transplant through early diagnosis and adequate management of hypertension and dyslipidemia

Despite correction of underlying solid organ failure by transplantation, pediatric transplant recipients still have increased mortality rates compared to the general pediatric population, in part due to increased cardiovascular risk. In particular, pediatric kidney and non-kidney transplant recipients with chronic kidney disease have significant cardiovascular risk that worsens with declining kidney function. Biomarkers associated with future cardiovascular risk such as casual and ambulatory hypertension, dyslipidemia, vascular stiffness and calcification, and left ventricular hypertrophy can be detected throughout the post-transplant period and in patients with stable kidney function. Among these, hypertension and dyslipidemia are two potentially modifiable cardiovascular risk factors that are highly prevalent in kidney and non-kidney pediatric transplant recipients. Standardized approaches to appropriate BP measurement and lipid monitoring are needed to detect and address these risk factors in a timely fashion. To achieve sustained improvement in cardiovascular health, clinicians should partner with patients and their caregivers to address these and other risk factors with a combined approach that integrates pharmacologic with non-pharmacologic approaches. This review outlines the scope and impact of hypertension and dyslipidemia in pediatric transplant recipients, with a particular focus on pediatric kidney transplantation given the high burden of chronic kidney disease-associated cardiovascular risk. We also review the current published guidelines for monitoring and managing abnormalities in blood pressure and lipids, highlighting the important role of therapeutic lifestyle changes in concert with antihypertensive and lipid-lowering medications.

Sleep-Disordered Breathing and 24-Hour Ambulatory Blood Pressure Monitoring in Renal Transplant Patients: Longitudinal Study

Background Sleep-disordered breathing (SDB) is considered a strong risk factor for hypertension in the general population. This disturbance is common in end-stage kidney disease patients on long-term hemodialysis and improves early on after renal transplantation. Whether SDB may be a risk factor for hypertension in renal transplant patients is unclear. Methods and Results We investigated the long-term evolution of simultaneous polysomnographic and 24-hour ambulatory blood pressure (BP) monitoring recordings in a cohort of 221 renal transplant patients. Overall, 404 paired recordings were made over a median follow-up of 35 months. A longitudinal data analysis was performed by the mixed linear model. The apnea-hypopnea index increased from a median baseline value of 1.8 (interquartile range, 0.6-5.0) to a median final value of 3.6 (interquartile range, 1.7-10.4; P=0.009). Repeated categorical measurements of the apnea-hypopnea index were directly associated with simultaneous 24-hour, daytime, and nighttime systolic ambulatory BP monitoring (adjusted analyses; P ranging from 0.002-0.01). In a sensitivity analysis restricted to 139 patients with at least 2 visits, 24-hour, daytime, and nighttime systolic BP significantly increased across visits (P<0.05) in patients with worsening SDB (n=40), whereas the same BP metrics did not change in patients (n=99) with stable apnea-hypopnea index. Conclusions In renal transplant patients, worsening SDB associates with a parallel increase in average 24-hour, daytime, and nighttime systolic BP. These data are compatible with the hypothesis that the link between SDB and hypertension is causal in nature. Clinical trials are, however, needed to definitively test this hypothesis.