Effectiveness of immunosuppressive therapy in older patients with aplastic anemia. European Group for Blood and Marrow Transplantation Severe Aplastic Anaemia Working Party.

BACKGROUND: Immunosuppressive therapy has been used for successful treatment of severe aplastic anemia, but little information is available on outcome in older patients.

OBJECTIVE: To evaluate outcome in patients older than 50 years of age who received immunosuppressive therapy for aplastic anemia.

DESIGN: Retrospective cohort study.

SETTING: 56 centers of the European Group for Blood and Marrow Transplantation (EBMT).

PATIENTS: 810 patients with aplastic anemia reported between 1974 and 1997. Patients were evaluated according to age group: 60 years of age or older (n = 127), 50 to 59 years of age (n = 115), and 20 to 49 years of age (n = 568; reference group).

INTERVENTION: Antilymphocyte globulin, cyclosporine, or both.

MEASUREMENTS: Survival, cause of death, response to treatment, relapse rate, and risk for late complications were analyzed in all patients and by age group.

RESULTS: The 5-year survival rate was 57% (95% CI, 46% to 66%) in patients 50 to 59 years of age and 50% (CI, 39% to 60%) in patients 60 years of age or older compared with 72% (CI, 68% to 76%) in patients younger than 50 years of age (P < 0.001). Response to therapy, relapse rate, and risk for clonal complications were similar in all three age groups (P > 0.2). Age was significantly associated with an increased risk for death (relative risk compared with patients 20 to 49 years of age, 1.80 [CI, 1.29 to 2.52] for patients 50 to 59 years of age and 2.57 [CI, 1.87 to 3.53] for patients > or = 60 years of age), mainly because of bleeding or infection (P = 0.02). Response to immunosuppressive therapy in all patients at 12 months was 62% (CI, 58% to 66%); no difference was seen among the age groups in multivariate analysis (P > 0.2). Sixty-six of the 379 responding patients (17%) subsequently had relapse. The risk for clonal disorders at 10 years was 20% (CI, 15% to 27%).

CONCLUSIONS: Response to immunosuppression in aplastic anemia is independent of age, but treatment is associated with increased mortality in older patients.