ACE Inhibitors, Angiotensin Receptor Blockers Have Heart Benefits in Hemodialysis Patients
Treatment with an ACE inhibitor or angiotensin-receptor blocker (ARB) is associated with decreased left ventricular (LV) mass but not a decrease in cardiovascular event risk in hemodialysis (HD) patients, according to a recent meta-analysis.
Researchers at the University of Calgary in Alberta led by Brenda R. Hemmelgarn, MD, pooled data from eight randomized controlled trials looking at the effect of ACE inhibitor or ARB treatment on cardiovascular events or LV mass in adults receiving long-term hemodialysis.
Of the eight trials, three had cardiovascular events as the primary outcome. These trials included a total of 837 patients (419 in the intervention groups and 418 in the control groups). Treatment duration ranged from 19 to 36 months. The other five trials had LV mass as the primary outcome and included a total of 151 patients (82 in the intervention groups and 69 in the control groups). Treatment duration ranged from six to 12 months.
Patients treated with an ACE inhibitor or ARB experienced a significant reduction in LV mass compared with controls, with a weighted mean difference (WMD) of 15.4 g/m2, the investigators reported in the Clinical Journal of the American Society of Nephrology (2010; published online ahead of print).
WMD is the average of differences between the intervention and controls groups from each study, the authors explained. Each trial's contribution to the average is based on the variance within that trial.
The decrease appeared to be independent of BP changes because there was no significant difference in the change in systolic BP at study end. The investigators found no significant decrease in the pooled risk of cardiovascular events, but they noted that “this may have been due to inadequate study power despite pooling.”
The authors observed that the reduction in LV mass associated with ACE inhibitor or ARB use is potentially important because studies have shown that regression of LV hypertrophy predicts survival of HD patients and is a valid surrogate for improved cardiovascular end points in some nondialysis cohorts.