ATC 2012 Report – Hypertension among kidney transplant recipients still a big challenge

by Thomas R. Collins – The blood pressure of the kidney transplant recipient at the University of Glasgow kept climbing. But it wasn’t without effort from physicians.

The patient was put on the calcium channel blocker amlodipine, which did not have much effect. About a year following transplantation, doctors tried valsartan, an angiotensin II receptor antagonist. After that, the hypertension only worsened.

Then, furosemide for swelling reduction was tried, followed by the beta blocker atenolol and the alpha blocker doxazosin. But the blood pressure remained high four years after the transplantation.

Alan Jardine, MD, Professor of Renal Medicine at the University of Glasgow with a special interest in cardiovascular complications after kidney disease and kidney transplantation, pointed to the patient as an example of a common problem among transplant recipients. His observations were made at the 2012 American Transplant Congress.

It’s a condition brought about by reduced glomerular filtration rate, sodium retention and other factors associated with kidney transplants.

And how to go about handling high blood pressure in these patients remains a challenge for doctors, Dr Jardine said.

He likened the hypertension problem to the Queen of England, known as someone who simply waves to people a lot — and has been thought of that way for years.

“Not very much has changed in hypertension,” Dr Jardine said. “We’re still between the same motions and you have to look hard for some big advances.”

Much of the problem comes straight from the drugs themselves, with steroids, cyclosporine, calcineurin inhibitors, and rapamycin inhibitors all having negative effects on factors associated with cardiovascular risk, from hypertension to cholesterol levels and diabetes risk.

But getting control of blood pressure is a serious concern, since it has been shown that the higher the one-year systolic blood pressure, the worse the rate of graft survival.¹

Guidelines can only be so helpful, since very often they are open-ended. He pointed to the KDIGO (Kidney Disease: Improving Global Outcomes) parameters, which recommend measuring blood pressure at each clinic visit and suggest maintaining a systolic pressure lower than 130 and diastolic below 80. As for treatment, the guidelines say that the use of any agent is acceptable, though the choice should be “influenced by time after transplant, the use of CNIs (calcinuerin inhibitors), presence of proteinuria and co-morbid conditions,” and as long as their interactions and side effects are monitored, Dr Jardine noted.

Where blood pressure is measured can be an overlooked factor, but studies have shown that a blood pressure measured in the office can often be significantly higher than it is when measured at home, where the patient is more comfortable and relaxed.²

Restricting intake of sodium is also a simple lifestyle measure that’s been shown to help reduce blood pressure.³

He noted that studies have shown that calcium channel blockers are favored over ACE inhibitors for graft function.⁴

ACE inhibitors are preferred for patients with proteinuria, he said, adding that modifying how immunosuppression medications are used should also be a consideration.

“Despite all this, we’re doing quite well,” he said. “Cardiovascular mortality is falling…. But we need trials.”

 

References:

1. Opelz G, Döhler B et al. Am J Transplant 2005; 5(11): 2725-31
2. Sberro-Soussan R, Rabant M, Snanoudj R, Zuber J, Bererhi, L et al. J Transplantation 2012 (Vol 12); doi:10.1155/2012/702316
3. Van der Berg E, Geleijnse J, Brink E, Van Baak M  et al. NDT 2012; 27(8): 3352 – 9. ePub 2012 Apr 12
4. Cross N, Webster A, Masson P, O’Connell P, Craig JC. Transplantation 2009; 88(1): 7-18