Effect of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers on cardiovascular outcomes in dialysis patients: a systematic review and meta-analysis

Effect of angiotensin-converting enzyme inhibitors versus that of angiotensin receptor blockers on survival in patients undergoing hemodialysis: a nationwide observational cohort study

BACKGROUND

This study aimed to evaluate the patient survival rates based on the use of angiotensin-converting enzyme inhibitor (ACEI) or angiotensin II receptor blocker (ARB) in a large cohort of patients undergoing maintenance hemodialysis (HD).

METHODS

Data from a national HD quality assessment program were used in this retrospective study. The patients were classified into four groups based on the use of renin-angiotensin system blockers (RASBs) as follows: No group, patients without a prescription of any anti-hypertensive drugs including RASBs; Other group, patients with a prescription of anti-hypertensive drugs excluding RASBs; ACEI group, patients with a prescription of an ACEI; and ARB group, patients with a prescription of an ARB.

RESULTS

The 5-year survival rates in the no, other, ACEI, and ARB groups were 68.6%, 67.8%, 70.6%, and 69.2%, respectively. The ACEI group had the best patient survival trend among the four groups. In multivariable Cox regression analyses, no differences were observed between the ACEI and ARB groups. Among young patients and patients without diabetes or heart disease, the ACEI group had the best patient survival among the four groups. However, among patients with DM or heart disease, the ARB group had the best patient survival.

CONCLUSIONS

Our study found that patients receiving ACEI and ARB had comparable survival. However, patients receiving ARB had better survival in the subgroups of patients with DM or heart disease, and patients receiving ACEI had better survival in the subgroup of young patients or patients without diabetes or heart disease.

Resistant Hypertension in Dialysis: Epidemiology, Diagnosis, and Management

Apparent treatment-resistant hypertension is defined as an elevated BP despite the use of ≥3 antihypertensive medications from different classes or the use of ≥4 antihypertensives regardless of BP levels. Among patients receiving maintenance hemodialysis or peritoneal dialysis, using this definition, the prevalence of apparent treatment-resistant hypertension is estimated to be between 18% and 42%. Owing to the lack of a rigorous assessment of some common causes of pseudoresistance, the burden of true resistant hypertension in the dialysis population remains unknown. What distinguishes apparent treatment-resistance from true resistance is white-coat hypertension and adherence to medications. Accordingly, the diagnostic workup of a dialysis patient with apparent treatment-resistant hypertension on dialysis includes the accurate determination of BP control status with the use of home or ambulatory BP monitoring and exclusion of nonadherence to the prescribed antihypertensive regimen. In a patient on dialysis with inadequately controlled BP, despite adherence to therapy with maximally tolerated doses of a β -blocker, a long-acting dihydropyridine calcium channel blocker, and a renin-angiotensin system inhibitor, volume-mediated hypertension is the most important treatable cause of resistance. In daily clinical practice, such patients are often managed with intensification of antihypertensive therapy. However, this therapeutic strategy is likely to fail if volume overload is not adequately recognized or treated. Instead of increasing the number of prescribed BP-lowering medications, we recommend diet and dialysate restricted in sodium to facilitate achievement of dry weight. The achievement of dry weight is facilitated by an adequate time on dialysis of at least 4 hours for delivering an adequate dialysis dose. In this article, we review the epidemiology, diagnosis, and management of resistant hypertension among patients on dialysis.