Appropriate hematocrit levels of erythropoietin supplementary therapy in end-stage renal failure complicated by coronary artery disease.

OBJECTIVE

To investigate an appropriate hematocrit (Hct) for managing renal anemia complicated by angina pectoris at rest.

DESIGN

Nonrandomized, retrospective and prospective observational study.

SETTING

Sapporo Medical University Hospital, Sapporo, Japan.

PATIENTS

Thirty-two anemic patients (aged 62 +/- 10 years, range 40 to 78) with rest angina in end-stage renal failure.

INTERVENTIONS

Serial changes of exercise tolerance (estimated metabolic equivalents [METs] on stress electrocardiography produced by improvement of patients' Hct, using recombinant human erythropoietin (rHuEPO). Adverse effects, such as deteriorating systemic hypertension, were investigated with regard to the severity of coronary arteriographic findings (Leaman's score) and cardiac events within a six-month period.

MAIN RESULTS

Higher Hct was clearly correlated with better estimated METs: when Hct was less than 20%, MET was 1.4 +/- 0.5; with 20% < or = Hct < 25% 2.1 +/- 1.4; with 25% < or = Hct < 30% 3.1 +/- 1.6; and with 30% < or = Hct < 35% 4.9 +/- 1.1. Patients with cardiac events (elective balloon angioplasty [n = 5], bypass surgery [n = 1], myocardial infarction [n = 2] and hospital death from congestive heart failure [n = 3]) had advanced coronary lesions compared with patients without coronary events (Leaman's score 15.9 +/- 9.3 versus 7.3 +/- 4.4, respectively, P < 0.01) and lower exercise capacity at 25% < or = Ht < 30% (estimated METs 2.4 +/- 1.2 versus 3.9 +/- 1.9, respectively, P < 0.05). Moreover, there was an inverse linear correlation between estimated METs and Leaman's score only when Hct was over 25%. In prospectively examined subjects (n = 16), Hct 35% or greater without systemic hypertension was obtained in only seven (44%), and no additional effect on exercise tolerance was expected when Hct was 35% or greater.

CONCLUSIONS

Managing renal anemia with 30% < or = Hct < 35% with rHuEPO is considered an appropriate therapy in patients with end-stage renal failure complicated by rest angina.