PHILADELPHIA—Rigorous blood pressure control can reduce the rate of increase in total kidney volume (TKV) in young hypertensive patients with autosomal dominant polycystic kidney disease (ADPKD) and relatively preserved kidney function, a researcher reported at the 2014 Kidney Week meeting.
“Low blood pressure treatment in healthy young hypertensive ADPKD patients with renin-angiotensin-system blockade is well tolerated and safe and results in a 14.2% slower rate of total kidney volume growth over 5 years, is associated with reduced left ventricular mass index, urinary albumin excretion, and renal vascular resistance,” said Arlene B. Chapman, MD, of Emory University in Atlanta.
Dr. Chapman presented the findings of a placebo-controlled, double-blind study of 558 hypertensive ADPKD patients aged 15–49 years who had an estimated glomerular filtration rate (eGFR) above 60 mL/min/1.73 m2.
She and her colleagues compared the effect of the ACE inhibitor lisinopril alone or in combination with the angiotensin receptor blocker (ARB) telmisartan and the effect of low versus standard blood pressure (BP) on the annual percent change in TKV. The researchers defined low BP as 95–110/60–75 mm Hg and standard BP as 120–130/70–80 mm Hg.
Results showed that subjects in the low BP group experienced a 14.2% slower annual increase in TKV than the standard BP group (5.6% vs. 6.6% per year), but did not differ significantly between the patients receiving lisinopril alone or in combination with telmisartan.
Dr. Chapman and her colleagues also found that the low BP group experienced a significantly greater decrease in left ventricular mass index and urine albumin excretion than the standard BP group (-1.17 vs. 0.57 g/m2 per year and -3.77% vs. -2.43%, respectively). Tighter BP control did not significantly affect overall change in eGFR.
In a companion double-blind, placebo-controlled trial, the results of which also were presented at the meeting, Vicente E. Torres, MD, PhD, of Mayo Clinic in Rochester, Minn., and collaborators studied 486 ADPKD patients aged 18–64 years with stage 3 chronic kidney disease and 5–8 years of follow-up. Patients were randomized to receive lisinopril and placebo or lisinopril and telmisartan titrated to achieve a BP of 110–130/70–80 mm Hg.
Treatment with lisinopril alone or in combination with telmisartan lowered urinary aldosterone excretion and adequately controlled BP. The researchers observed no significant difference in the composite primary outcome (time to death, end-stage renal disease, or a 50% reduction from the baseline eGFR) and rate of eGFR decline.
The presentation of the studies at Kidney Week coincided with their online publication in The New England Journal of Medicine.