CHICAGO – A U.S. foundation that makes recommendations for the management of patients with chronic kidney disease recently set a blood pressure goal of less than 140/90 mm Hg for these patients, upping the target from the 130/80 mm Hg level established in 2003 by the seventh report of the Joint National Committee on Prevention, Detection, and Evaluation, and Treatment of High Blood Pressure (JNC 7) (Hypertension 2003;42:1206-52).
The new goal, made by a panel assembled by the Kidney Disease: Improving Global Outcomes (KDIGO) foundation, will appear in a journal article within the next few weeks, Dr. George L. Bakris said at the meeting.
Mitchel L. Zoler/IMNG Medical Media
Dr. George L. Bakris
"We knew when we wrote JNC7 that a target systolic blood pressure of less than 130 mm Hg was not that defensible, but a number of us were concerned that if we set a higher target, most physicians would be content with 145 mm Hg; that’s what drove setting 130 mm Hg," said Dr. Bakris, a member of the JNC 7 writing group, as well as a member of the panel that wrote the new KDIGO guidelines.
Clear-cut, albeit limited, evidence from randomized, controlled trials addresses the appropriate target systolic blood pressure in patients with chronic kidney disease. Three controlled studies addressed the issue, none included patients with diabetic nephropathy, and all three enrolled patients with stage 3 chronic kidney disease, defined as a glomerular filtration rate of 30-59 mL/min per 1.73 m2.
For example, results from the REIN (Ramipril Efficacy in Nephropathy)-2 trial showed that intensive blood pressure lowering to less than 130/80 mm Hg was no more effective than was treatment to a conventional target, diastolic pressure less than 90 mm Hg, for preventing progression of patients to end-stage renal disease (Lancet 2005;365:939-46). And results from AASK (African-American Study of Kidney Disease and Hypertension) showed that intensive blood pressure reduction produced no improvement in the outcome of lost renal function, end-stage renal disease, or death compared with conventional blood pressure control (JAMA 2002;288:2421-31).
A recent observational study had similar findings. Results from the Kidney Early Evaluation Program showed that in more than 16,000 American adults with kidney disease, patients with a baseline systolic blood pressure of less than 130 mm Hg did no better than did patients with a baseline pressure of 130-139 mm Hg for progression to end-stage renal disease during 3 years of follow-up (Arch. Int. Med. 2012;172:41-7).
These results show that you "don’t need to get the [blood pressure] numbers down to the floor to get benefit," said Dr. Bakris, who is a professor of medicine and director of the hypertension center at the University of Chicago.
"A goal of less than 140/90 mm Hg is for everyone with chronic kidney disease, including patients with proteinuria. That may be a little surprising, but the evidence [supporting a lower goal in patients with proteinuria] is soft. This doesn’t mean that you can’t go lower than 130 mm Hg, but the evidence doesn’t really support it."
In addition, while ACE inhibitors and angiotensin-receptor blockers (ARBs) are "definitely indicated" as primary antihypertensive agents for patients with kidney disease, "there is no evidence that using these two classes in combination in patients with advanced kidney disease or in normotensive patients with kidney disease will change the natural history of the disease. The evidence that a combination of an ACE inhibitor and an ARB will reduce proteinuria is pretty good, but we don’t know whether that will lead to benefit in terms of slowing progression," Dr. Bakris said.
Dr. Bakris said that he has received research grants from Forest, Novartis, and Relypsa, that he has been a consultant to Takeda, Servier, Abbott, CVRx, Johnson & Johnson, and Eli Lilly, and that he has been a speaker for Takeda and Novartis.