I have never been a fan of vitamins. They fall in to a category of interventions with presumed safety and benefit. An important study in the Journal of the American Medical Association shows the opposite; that vitamins can cause harm in patients with chronic kidney disease.

The following appears on the BC Renal Agency Website:

In April, the Journal of the American Medical Association (JAMA) published a study that looked at whether high doses of B vitamins (folic acid, B12, B6) helped people with kidney disease due to diabetes. The study found that high doses of these vitamins were actually harmful. Study participants who took the vitamins had an increased risk of heart attack and stroke. They also had reduced kidney function.

Many studies have questioned the effectiveness of hydrochlorothiazide (HCTZ) versus chlorthalidone as a diuretic. In fact, most large scale trials that have used HCTZ have been disappointing (e.g. ACCOMPLISH) while those using chlorthalidone have been largely positive (e.g. ALLHAT). While this might seem like an over-simplification, many hypertension experts agree with it.

In the latest twist to this story, Takeda Pharmaceuticals have created a fixed dose combination with it's new ARB azilsartan with chlorthalidone - in stark contrast to all other ARB and ACE inhibitor counterparts. As it it turns out, they may be on to something ( continued ... )

ScienceDaily (May 6, 2010) — Two-year results from phase III clinical trials show the experimental immunosuppressive drug belatacept can better preserve kidney function in kidney transplant recipients while preventing graft rejection when compared with the standard immunosuppressive drug cyclosporine.

Over the past 2 years, considerable excitement has been building over the results of the ACCOMPLISH study. This trial suggested that the combination of benazapril plus amlodipine is superior to benazapril plus hydrochlorothiazide for the prevention of a composite cardiovacular outcome. While there are methodological concerns regarding this trial that make me question its generlizability, it is thought-provoking to consider that one medication combination is superior to another even if blood-pressure between the 2 groups is negligible.

In the latest issue of Lancet, a follow-up paper suggests that benzapril-amlodipine prevented renal outcomes more-so than in the benazapril-hydrochlorothiazide arm. However, as the excellent accompanying editorial points out, all is not as it appears. (continued...)

Hyperphosphatemia has been been linked to poor patient outcomes, including a link to higher mortality. This relationship has been inferred by several retrospective and observational studies. In fact, the relationship between hyperphosphatemia and death is one of the most consistently espoused theories in all of nephrology. There is just problem however; there has never been a randomized trial to confirm this association.

In the latest issue of Nephrology Dialysis and Transplantation, Smith et al cast doubt on this long-held belief. In their retrospective CKD-inception cohort study, there was no association between hyperphosphatemia and death, though there was less risk of renal replacement therapy in patients with better phosphorus control.

This finding is by no means conclusive. I continue to aggressively treat hyperphosphatemia. However, it does lend further support for a large-scale randomized trial to study this seemingly unimpeachable belief.

The TREAT Trial was presented at the ASN in San Diego. This much publicized trial examined the role of Aranesp in the management of diabetic patients with CKD. One group was randomized to receive Aranesp with a hemoglobin target of 130 g/l while the control group was given placebo and treated with Aranesp only if their hemoglobin fell below 90 g/l.

There was no advantage to the group given Aranesp and a statistically significant increase in strokes observed in the the treatment group. Below is a link to the article from NEJM and the accompanying editorial written by renowned nephrologist, Dr. Phil Marsden of the University of Toronto.

It is worth noting, that the treatment group was targeted to a higher hemoglobin than we now conventionally use. Furthermore, the dose of Aranesp was more than double the typical dosages used by the majority of my predialysis patients. As has been observed in other studies where high hemoglobin seems harmful, the dose of Aranesp required might explain the observation of harm. Perhaps those patients who respond to lower dosages and those whose hemoglobins remain with target would be perfectly safe to continue.

No Statistically Significant Difference in Cardiovascular and Renal Composite Endpoints Between Aranesp and Placebo

THOUSAND OAKS, Calif., Aug. 25 /PRNewswire-FirstCall/ -- Amgen (Nasdaq: AMGN) today announced that in a large, randomized, double-blind, placebo-controlled, Phase 3 study of patients with chronic kidney disease (CKD) (not requiring dialysis), anemia and type-2 diabetes (the Trial to Reduce CardiovascularEndpoints with Aranesp((R)) Therapy, or TREAT), treatment of anemia with Aranesp((R) )(darbepoetin alfa) to a hemoglobin target of 13 g/dL had no statistically significant effect on either of two primary endpoints compared with placebo treatment. The two primary endpoints were a composite of time to all-cause mortality or cardiovascular morbidity (including heart failure, heart attack, stroke, or hospitalization for myocardial ischemia) and a composite of time to all-cause mortality or chronic renal replacement therapy. Among the elements that formed these composite endpoints, an excess of stroke events (a labeled risk of Aranesp therapy) occurred in the Aranesp-treated patients compared to those receiving placebo.

 

In the latest edition of the Journal American Association of Nephrology, investigators report that sodium bicarbonate administration delays the progression of kidney disease to end-stage renal failure. 134 adult patients with CKD (creatinine clearance [CrCl] 15 to 30 ml/min per 1.73 m²) and serum bicarbonate 16 to 20 mmol/L to either supplementation with oral sodium bicarbonate or standard care for 2 yr. With this simple intervention, patients receiving sodium bicarbonate were significantly less likely to experience rapid progression (9 versus 45%; relative risk 0.15; 95% confidence interval 0.06 to 0.40; P < 0.0001). Compared with the control group, decline in CrCl was slower with bicarbonate supplementation (5.93 versus 1.88 ml/min 1.73 m²; P < 0.0001). Nutritional parameters were improved as well. This very simple intervention, practiced variably by nephrologists, shows great promise in the management of patients with chronic kidney disease.

Click here to download the PDF

By Crystal Phend, Staff Writer, MedPage Today
Published: May 12, 2009
Reviewed by Zalman S. Agus, MD; Emeritus Professor
University of Pennsylvania School of Medicine.

SAN FRANCISCO, May 12 -- Ambulatory blood pressure monitoring didn't explain the cardiovascular advantage of calcium channel blockade found in the ACCOMPLISH trial, researchers said.

The primary findings of that trial revealed a 20% reduction in cardiovascular mortality and morbidity with the calcium channel blocker amlodipine (Norvasc) versus the diuretic hydrochlorothiazide (Microzide) as the initial antihypertensive in combination with the ACE inhibitor benazepril (Lotensin).

But in a secondary analysis of ACCOMPLISH results, 24-hour blood pressure monitoring revealed no difference in blood pressure control between the regimens, Kenneth Jamerson, M.D., of the University of Michigan in Ann Arbor, and colleagues found.

These results affirm that the calcium channel blocker combination has some "pleiotropic" benefits beyond blood pressure lowering alone, Dr. Jamerson reported at the American Society of Hypertension meeting.
Action Points  

    * Note that guidelines from the National Heart, Lung, and Blood Institute (JNC 7) recommend thiazide-type diuretics as initial therapy for most hypertensive patients, whether alone or in combination with an agent from another class.


    * Note that this study was published as an abstract and presented orally at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.

"It really does matter what agent you use," he said.

After the primary report of the data, concerns had arisen that lower blood pressure in the calcium channel blocker group biased the results, commented co-author George Bakris, M.D., of the University of Chicago, who moderated a press conference at which the findings were presented. (See ACC: Calcium Channel Blocker Beats Diuretic for Initial BP Combo Therapy)

Also, the trial used hydrochlorothiazide rather than the longer-acting diuretic chlorthalidone, which could have meant less blood pressure control over the full 24 hours compared with the other combination regimen.

But the ambulatory blood pressure results lay these questions to rest, Dr. Jamerson said.

"This type of data has the potential to change the paradigm to treat blood pressure from mostly being diuretic-based combination therapy to being amlodipine with benazipril type regimens," he said.

In the analysis of 573 patients in ACCOMPLISH, the in-clinic systolic blood pressure after two years of treatment averaged 0.6 mm Hg lower with amlodipine plus benazipril compared with hydrochlorothiazide plus benazipril (129.7 versus 130.3 mm Hg, P=0.621).

But the 24-hour blood pressure average actually favored the diuretic-ACE combination (122.3 versus 123.9 mm Hg, P=0.128), as did daytime and nighttime averages (P=0.097 and P=0.332).

For diastolic pressure, the diuretic combination also had a small, 0.3-mm Hg advantage over 24 hours (P=0.7).

None of these were significant differences, and both groups attained greater than 80% blood pressure control rates (81.3% with the calcium channel blocker and 84.9% with the diuretic combination, P=0.243).

Dr. Bakris said that a calcium channel blocker may have "pleiotropic" benefits for endothelial function and the atherosclerotic process that may have lowered cardiovascular risk despite similar blood pressure.

However, some at the late-breaking clinical trials session where the research was presented were skeptical.

Marvin Moser, M.D., of Yale University, who moderated the session, cautioned that the conclusions of the trial may have been overstated.

"The weight of data suggests it's the blood pressure level and not the specific drug," he said.

Guidelines from the National Heart, Lung, and Blood Institute (JNC 7) recommend thiazide-type diuretics as initial therapy for most hypertensive patients, whether alone or in combination with an agent from another class.

"Diuretics have held up as well as anything else," Dr. Moser said. "Before we abandon them we need further confirmation."

Another study presented at the same session, on which Dr. Bakris was also a co-author, suggested there was no difference between agents for left ventricular hypertrophy regression. (See ASH: Lower Blood Pressure Trumps Regimen in LV Remodeling)

Dr. Bakris noted that this surrogate endpoint may be important, but doesn't capture broader cardiovascular effects or the more important mortality endpoint.

Many nephrologists, myself included, are eager to find alternatives to cyclophosphamide in the management of lupus nephritis. As many of these patients are young men and women of child-bearing age, the effects of cyclophosphamide on fertility, along with bone marrow and other adverse effects make alternative medications more attractive. Several studies have suggested that mycophenolate mofetil (MMF) may be superior and less toxic than cyclophosphamide in the management of lupus nephritis. In the May issue of the Journal of the American Society of Nephrology, investigators report the result of a study comparing IV cyclophsphamide with oral MMF. While a reprint is not yet available for review, preliminary reports suggest that MMF is slightly more effective and less toxic in this trial. In a 24-week open-label induction study of 370 patients with class III-V lupus, there were no differences in the primary end-point (a prespecified decrease in urine protein/creatinine ratio and stabilization or improvement in serum creatinine) or the secondary end-point (complete renal remission, systemic disease activity and damage, and safety).  As well, there were no differences in the rate of adverse events between the 2 groups. For the studied patients, IV cyclophosphamide and oral MMF share similar efficacy and harm. This study adds to the growing evidence base showing no difference between these 2 treatment strategies.

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