[Aplastic anemia--clinical characteristics and survival analysis]

Aplastic anaemia is a relatively rare disease, characterized by the loss of haemopoietic "stem" cells in the bone marrow, exchanged with fat cells and pancytopenia. The treatment of this disease consists of supportive therapy with blood products and finally phase, where there are two possibilities: immunosuppression and bone marrow transplantation. Immunosuppression means the use of antilymphocyte or antithymocyte globulins, anabolic steroids, Cyclosporine A, corticosteroids, and recently haemopoietic growth factors [1]. The advantage of bone marrow transplantation compared to other kinds of treatment has been established in multicentric trials [2]. Goals of study: 1. To show and analyze clinical characteristics in patients with aplastic anaemia; 2. To study survival according to gender, age and kinds of treatment.

Thirty three patients with aplastic anaemia are included in the study. They were treated at the Institute of Haematology, Clinical Centre of Serbia, from 1988 to 1995. For description of data we used parameters for the arithmetic mean and standard deviation; for nonparametric tests-median. Student's T-test was used for comparison of differences among the mean values from nonparametric analytic models. From nonparametric models, Fisher's test was used. For data analysis of survival Kaplan-Mayer's model was used.

Thirty three patients with aplastic anaemia were examined. There were 17 (52%) men and 16 (48%) women. The youngest patient was 15 and the oldest 73 years. The average age of patients was 40.18 years. In the group up to 30 years there were 16 (48%) patients. In the group from 31 to 45 years there were 4 (12%) patients. In the group from 46 to 60 years there were 4 (12%) patients, and in the group from 61 to 75 years 9 (28%); clinical signs (fatigue, exhaustion) and anaemic signs (pallor) were present in all patients (33). In 12 (36%) patients high body temperature was established and in 21 (64%) patients there was no temperature. Signs of haemorrhagic syndrome were established in 26 (79%) patients and 7 (21%) patients had no such signs. No significant statistical difference in survival (Lee-Desu = 0.071; DF = 1; p = 0.789) related to sex, was observed. According to the duration of the disease by year, and over this period, the difference was statically very significant (Lee-Desu = 20.735; DF = 1; p = 0.000). Therefore, in patients with a longer duration of the disease than one year the chance for a longer survival is better. We compared the group of patients treated with antilymphocytic globulin with the group treated with other methods (androgenic hormones and Prednisolone, Cyclosporine A and bone marrow transplantation). Between these two groups the difference was statistically significant (Lee-Desu = 2.742; DF = 1; p = 0.018). Therefore, survival of patients of the second group was longer thanks to a successful bone marrow transplantation. The group of patients treated by bone marrow transplantation was compared with the group of patients treated with other three methods; the difference was statistically significant (Lee-Desu = 7.346; DF = 1; p = 0.006). The best method of treatment is bone marrow transplantation in comparison to the other three methods. Survival was also analyzed in all four studied age groups. No statistically significant difference was found.

Aplastic anaemia is a serious, relatively rare illness, appearing with almost equal frequency in men and women. Two peaks were noticed: in the younger age group up to 30 years (48%) and over 60 years (27%). According to survival, there was a group with short survival, up to 12 months, and a group with longer survival, over 12 months. Gender and age had no influence on duration of survival. Only the duration of the disease had a positive effect on survival. In comparison to other methods, the most efficacious treatment was allogenic bone marrow transplantation.