Treatment of hypertension in renal transplant recipients

Prevalence and Hypertension Treatment Schedule in Hemodialysis Patients and Renal Transplant Recipients in 2006 and 2014/2016

BACKGROUND

Hypertension is often recognized in both hemodialysis patients (HDp) and renal transplant recipients (RTRs). The aim of the study was the evaluation of hypertension prevalence and treatment schedule and the achievement of the control of blood pressure according to the Polish Society of Hypertension, European Society of Hypertension, Joint National Committee, and American College of Cardiology/American Heart Association 2017 recommendations.

MATERIALS AND METHODS

Observations were done in 2 distinct periods of time: the year 2006 and the years 2014/2016. In 2006, 56 HDp and 316 RTRs were studied. In 2014/2016, 85 HDp and 818 RTRs were studied. The antihypertensive treatment analysis was based on medical records from visits in RTRs and dialyses in HDp.

RESULTS

Cardiovascular diseases were diagnosed in 71.4% (2006) and 65.9% (2016) in HDp; 17.7% (2006) and 21.5% (2014) in RTRs. Diabetes was observed in 39.3% (2006) and 34.1% (2016) in HDp; 16.5% (2006) and 23.2% (2014) in RTRs. The target blood pressure control was achieved in 64.3% (2006) and 49.4% (2016) of HDp and in 61.4% (2006) and 45.7% (2014) of RTRs. Three drugs (28.6% and 33.5% in 2006; 30.6% and 29.1% in 2016/2014) or 2 antihypertensive drugs (19.6% and 26.9% in 2006; 22.4% and 27.1% in 2016/2014) were used in HDp and RTRs, respectively. The majority of HDp and RTRs were treated with ß-blockers followed by calcium channel blockers.

CONCLUSIONS

The target blood pressure control was achieved in a low percentage of HDp and RTRs. RTRs required multidrug antihypertensive therapy to control blood pressure more often than HDp.

Management of hypertension and factors affecting its control in Jordanian renal transplant recipients

BACKGROUND

Hypertension affects 70-90 % of all kidney transplant recipients. It is associated with poor graft survival and is a contributing factor to the increased cardiovascular mortality. The reasons for the insufficient blood pressure control in transplanted patients have not been thoroughly investigated.

OBJECTIVE

To evaluate the extent of blood pressure control in Jordanian hypertensive renal transplant recipients and to assess factors associated with such control.

SETTING

Three outpatient renal transplant clinics in Amman.

METHOD

A cross-sectional observational study including 181 patients. We have considered blood pressure <130/80 mm Hg as controlled hypertension. Bivariate and multivariate logistic regression analyses were used to determine clinical factors associated with achievement of blood pressure control.

MAIN OUTCOME MEASURES

Proportion of patients who achieved hypertension control and clinical factors associated with good blood pressure control.

RESULTS

Mean systolic blood pressure was 128.6 ± 16.3 mm Hg and mean diastolic blood pressure was 82.8 ± 11.5 mm Hg. Blood pressure control was achieved only in 58 % of patients. The most commonly prescribed antihypertensives were calcium channel blockers (58 %) followed by beta-blockers (44 %). In bivariate analysis, female gender (p = 0.017) and creatinine clearance (p = 0.002) were positively associated, while number of antihypertensive medications was inversely associated (p = 0.04) with achievement of blood pressure control. After including these factors in multivariate logistic regression analysis, only creatinine clearance remained independently associated with hypertension control (odds ratio, OR 1.04; 95 % confidence interval [CI] 1.01-1.06; p = 0.003).

CONCLUSION

Blood pressure control among renal transplant recipients in Jordan was found to be inadequate. The only factor found to be independently associated with adequate blood pressure control was creatinine clearance.

Renin angiotensin system blockade in kidney transplantation: a systematic review of the evidence

ACE-inhibitors and angiotensin receptor blockers (ARB) slow the progression of renal disease in non-transplant patients. A systematic review of randomized trials (n = 21 trials with 1549 patients) was conducted to determine the effect of ACE-inhibitor or ARB use following kidney transplantation. With a median follow-up of 27 months, ACE-inhibitor or ARB use was associated with a significant decrease in glomerular filtration rate (-5.8 mL/min; 95% CI -10.6 to -0.99). ACE-inhibitor or ARB use resulted in a lower hematocrit (-3.5%; 95% CI -6.1 to -0.95), reduction in proteinuria (-0.47 gm/d; 95% CI -0.86 to -0.08) but no change in the serum potassium (0.18 mmol/L; 95% CI -0.03 to 0.40). ACE-inhibitor or ARB use results in clinically important reductions in proteinuria, hematocrit and glomerular filtration rate in renal transplant recipients, but there are insufficient data to determine the effect on patient or graft survival. Randomized trials of sufficient power and duration that examine these hard outcomes should be conducted. Until such trials are completed, this study provides quantitative estimates of the risks and benefits of ACE-inhibitor or ARB use that can be used by clinicians considering prescribing these medications to kidney transplant recipients or to researchers designing future trials.

Renal allograft protection with angiotensin II type 1 receptor antagonists

The renal benefits of agents inhibiting the renin-angiotensin-aldosterone system in renal transplant recipients, i.e. preventing the development of chronic graft nephropathy, are supposed but not finally proven. In a double-blind, placebo-controlled, cross-over study, we evaluated the influence of losartan on surrogate markers of tubular injury, urine excretion of transforming growth factor beta-1 (TGF-beta1) and amino-terminal propeptide of type III procollagen (PIIINP) in 16 patients after transplantation. The patients received randomly either losartan (50-100 mg daily) or the beta-blocker carvedilol (12.5-25 mg) for 8 weeks, allowing a placebo washout between treatments. The target office through blood pressure (BP) was below 130/85 mmHg. The BP did not differ in the treatment periods. Losartan significantly decreased N-acetyl-beta-d-glucosaminidase and alfa-1 microglobulin excretion relative to placebo and carvedilol. Urine excretion of TGF-beta1 and PIIINP was significantly lower after losartan. In conclusion, losartan reduces urine excretion of proteins associated with tubular damage and graft fibrosis.

Randomized placebo-controlled study on the effects of losartan and carvedilol on albuminuria in renal transplant recipients

BACKGROUND

The renoprotective effects of agents inhibiting the renin-angiotensin system in renal transplant recipients have been supposed but not finally proven. To shed more light on this issue, we performed a double-blind, placebo-controlled, crossover study to evaluate the influence of the AT-1 angiotensin II receptor blocker, losartan, on the surrogate marker of kidney injury, albuminuria, in patients after renal transplantation. The safety of this therapy was also evaluated.

METHODS

Fourteen of 16 patients (nine male, five female), age 45.36 +/- 3.04 years, 65.5 +/- 10.0 months after kidney transplantation, with hypertension and stable serum creatinine 123 +/- 4 micromol/L without proteinuria, completed the protocol. Each patient underwent two 8-week treatment periods (one with losartan 50-100 mg and one with carvedilol 12.5-25 mg) in random order, allowing an 8-week placebo washout between treatments. The target office trough blood pressure was below 130/85 mmHg.

RESULTS

The ambulatory blood pressure did not differ in the treatment periods. Losartan significantly reduced albuminuria relative to placebo and carvedilol (27.62+/-17.58 vs. 49.55 +/- 25.33 v. 44.77 +/- 21.9 mg/g creatinine; P < 0.01). A significant but not clinically relevant decrease in hemoglobin level after losartan was observed (losartan: 129 +/- 3.1 g/l, placebo: 134.2 +/- 3.2, carvedilol: 137.1 +/- 3.7; P < 0.001). Serum potassium, creatinine, creatinine clearance, and trough blood cyclosporine levels were unaffected.

CONCLUSION

Losartan decreases microalbuminuria in renal transplant recipients with clinically minimal side effects.

Renal Protective Effects of the Renin-Angiotensin-Aldosterone System Blockade: From Evidence-Based Approach to Perspectives

The renin-angiotensin-aldosterone system (RAAS) blockade is currently the best-documented treatment strategy to delay the progression of chronic nephropathies. Angiotensin-converting enzyme inhibitors (CEIs) or angiotensin II type 1 receptor antagonists (ARBs) should be used in every normotensive and hypertensive patient with chronic proteinuric nephropathy of both diabetic and non-diabetic origin. The therapy should be initiated as early as possible, bearing in mind that the renoprotection is more effective if used before overt proteinuria or a reduction in kidney function is present. The therapy should be offered to all patients, regardless of renal function, as well as to subjects with severely impaired glomerular filtration. CEIs and ARBs should be administered in therapeutic doses as high as possible to achieve maximal possible proteinuria reduction and systemic blood pressure target <130/80 mm Hg, and 125/75 mm Hg in those subjects with renal insufficiency who present with proteinuria above 1 g/24 h. The combined therapy with the concomitant use of CEIs and ARBs should be offered to all patients with proteinuric non-diabetic chronic nephropathies who do not achieve full and persistent remission of proteinuria with CEI or ARB alone. The article reviews an evidence-based approach on the use of RAAS-inhibiting agents in kidney diseases, considers treatment strategies in different clinical situations and discusses some perspectives related to the implementation of the RAAS blockade in renal protection.