Objectives: To study the effect of angiotensin-converting enzyme (ACE) polymorphisms II, ID, and DD on erythropoietin (EPO) requirement in patients on continuous ambulatory peritoneal dialysis (CAPD) therapy.
Design: Retrospective observational study.
Setting: CAPD Unit, Royal London/St. Bartholomews Hospital, London, UK.
Patients: 46 patients on the transplant waiting list (age 20-70 years), on CAPD therapy for an average of 28 months, seen consecutively over a period of 3 months in the outpatients department.
Main outcome measures: Primary end point: EPO dose requirement in different ACE genotypes. Secondary end points: C-reactive protein, ferritin, parathyroid hormone, Kt/V, duration of dialysis, folate, cause of renal failure, and whether or not patients were on ACE inhibitor therapy.
Results: There was a statistically significant difference (p < 0.05) in EPO requirement in the II/ID group compared to the DD group. The mean +/- standard error of EPO for the II/ID group was 144 +/- 15 U/kg/week, and for the DD group, 87 +/- 9 U/kg/week. The difference in EPO requirement could not be explained by age, C-reactive protein, ferritin, parathyroid hormone, Kt/V, duration of dialysis, folate, cause of renal failure, or whether or not patients were on ACE inhibitor therapy.
Conclusion: In CAPD patients, ACE genotype has predictive value when determining the EPO dosage, as the III/ID genotype may be associated with a suboptimal response.