Calcium channel blockers in the prevention of end stage renal disease: a review

Should ACE inhibitors or calcium channel blockers be used for post-transplant hypertension?

Arterial hypertension in renal transplant recipients warrants antihypertensive treatment. The preferable choice of antihypertensives that should be used in patients after kidney transplantation remains a matter of debate; however, calcium channel blockers (CCB) and angiotensin-converting enzyme inhibitors (ACEI) are currently the most commonly used antihypertensives. This educational review summarizes the current evidence about the effects of these two classes of medications in transplant recipients. Several studies have demonstrated that both classes of drugs can reduce blood pressure (BP) to similar extents. Meta-analyses of adult randomized controlled trials have shown that graft survival is improved in patients treated with ACEIs and CCBs, and that CCBs increase, yet ACEIs decrease, graft function. Proteinuria is usually decreased by ACEIs but remains unchanged with CCBs. In children, no randomized controlled study has ever been performed to compare BP or graft survival between CCBs and ACEIs. Post-transplant proteinuria could be reduced in children along with BP by ACEIs. The results of the most current meta-analyses recommend that due to their positive effects on graft function and survival, along with their lack of negative effects on serum potassium, CCBs could be the preferred first-line antihypertensive agent in renal transplant recipients. However, antihypertensive therapy should be individually tailored based on other factors, such as time after transplantation, presence of proteinuria/albuminuria, or hyperkalemia. Furthermore, due to the difficulty in controlling hypertension, combination therapy containing both CCBs and ACEIs could be a reasonable first-step therapy in treating children with severe post-transplantation hypertension.

Nondihydropyridine Calcium Channel Blockers for the Treatment of Proteinuria: A Review of the Literature

Objective: To review the use of nondihydropyridine calcium channel blockers (non-DHP CCBs) for the treatment of proteinuria in diabetic and nondiabetic kidney disease. Data Sources: A search using PubMed and MEDLINE, Scopus, and Google Scholar was performed from 1964 through February 2019 using the following search terms alone or in combination: verapamil, diltiazem, non-dihydropyridine calcium channel blocker, proteinuria, albuminuria, microalbuminuria, kidney disease, renal disease. Study Selection and Data Extraction: All prospective English-language trials examining one or more non-DHP CCB for the treatment of proteinuria were evaluated. Data Synthesis: A total of 13 clinical trials examining the use of non-DHP CCBs to treat proteinuria alone or in combination with angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) were included in the evaluation. Most studies evaluated patients with macroalbuminuria secondary to diabetes and hypertension. Verapamil was the most common agent studied. Non-DHP CCBs were effective in reducing proteinuria in diabetic kidney disease but did not reduce renal or cardiovascular outcomes in the one trial that evaluated clinical end points. They were generally well tolerated, with the most common adverse effect reported being constipation. Relevance to Patient Care and Clinical Practice: This review evaluates and summarizes the available evidence on non-DHP CCBs for treatment of proteinuria in patients with existing kidney disease. Conclusion: Non-DHP CCBs may be a reasonable therapeutic option for patients with diabetic kidney disease and persistent proteinuria despite maximum doses of ACE inhibitors or ARBs. Additionally, they may be reasonable alternatives to ACE inhibitors or ARBs if a contraindication or intolerance exists.

Antihypertensive therapy in nondiabetic chronic kidney disease: a review and update

Hypertension is an important contributor to progression of nondiabetic chronic kidney disease (CKD). Compelling observational evidence indicates that the divergence of blood pressure (BP) away from an ideal range in either direction is associated with a progressive rise in the risk of mortality and cardiovascular and renal disease progression. To date, various clinical trials and meta-analyses examining strict versus less intensive BP control in nondiabetic CKD have not conclusively demonstrated a renal advantage of one BP-lowering approach over another, except in certain subgroups such as proteinuric patients where evidence is circumstantial. As recent data have come to light suggesting that intensive BP control yields superior survival and cardiovascular outcomes in patients at high risk for cardiovascular disease, interest in the prospect of whether such benefit extends to individuals with CKD has surged. This review is a comprehensive analysis of antihypertensive literature in nondiabetic renal disease, with a particular emphasis on BP target.

Comparison of renal and vascular protective effects between telmisartan and amlodipine in hypertensive patients with chronic kidney disease with mild renal insufficiency

The present study was conducted to compare the renal and vascular protective effects of telmisartan and amlodipine in untreated hypertensive chronic kidney disease (CKD) patients with moderate renal insufficiency. Thirty hypertensive CKD patients were randomly assigned to receive telmisartan 40 mg (n = 15) or amlodipine 5 mg (n = 15) once daily for 12 months. Changes in blood pressure, serum creatinine, 24-h creatinine clearance (Ccr), proteinuria, brachial-ankle pulse wave velocity (baPWV), intima-media thickness (IMT), plasma interleukin-6 (IL-6), plasma matrix metalloproteinase (MMP)-9 and lipid profiles were monitored in all patients. Before treatment, there were no significant differences in these parameters between the telmisartan and amlodipine groups. Over the 12 month observation period, blood pressure decreased equally in both groups. However, serum creatinine, proteinuria, baPWV, IMT, plasma levels of IL-6 and MMP-9 and total cholesterol decreased and 24-h Ccr increased more strikingly in the telmisartan group than the amlodipine group. These data suggest that telmisartan is more effective than amlodipine for protecting renovascular functions, and potentially for ameliorating atherosclerosis, in hypertensive CKD patients with moderate renal insufficiency.

Hypertension and the kidney

The kidney could be the cause of essential hypertension which can also cause renal disease. High blood pressure is also very common in chronic kidney disease, and is moreover a well-known risk factor for a faster progression of kidney failure. Hypertension and kidneys are thus closely linked. Hypertension must be aggressively treated in patients suffering from chronic kidney disease, with a blood pressure goal of less than 130/80 mmHg, even lower than 125/75 mmHg when proteinuria is over 1g/day, using optimal and effective antihypertensive drugs. Among them, the blockers of the renin-angiotensin axis offer nephroprotective but also cardioprotective properties beyond their effect on blood pressure.

Transplantation as a therapeutic option for diabetic nephropathy

Diabetic nephropathy affects both type 1 and type 2 diabetic patients with a frequency of 20-30%. The first sign is microalbuminuria within a range of 30-300 mg/24h, frequently evolving towards frank proteinuria and renal failure. Tight glucose control, control of arterial hypertension with the use of ACEi or ARB can retard progression. Once renal failure is established, kidney transplantation can be considered for type 1 and type 2 diabetic patients. Quality of life and survival are improved with this procedure. In type 1 diabetes, simultaneous grafting of a kidney and pancreas considerably improves quality of life and diabetic complications. Surgical and infectious complications are sporadic drawbacks of this procedure. Pancreas transplantation alone (PTA) remains controversial, since a retrospective study in 2003 by Venstrom concluded that survival for PTA patients is worse than for comparable patients remaining on the waiting list. PTA can be considered for type 1 diabetic patients without advanced renal failure with severe and frequent metabolic instability (hypoglycaemia, ketoacidosis). Islet transplantation is still an experimental but promising procedure in highly selected patients, avoiding major abdominal surgery.