The effect of age in patients with acquired aplastic anaemia treated with immunosuppressive therapy: comparison of Adolescents and Young Adults with children and older adults

Summary The incidence of acquired aplastic anaemia ( AA ) peaks in adolescents and young adults ( AYA ). Although age has been associated with response after immunosuppressive therapy ( IST ), few data exist about the specific outcome of AYA . We retrospectively compared the outcome of 29 children (aged <15 years), 32 AYA (15–25 years) and 23 adults (>25 years) with AA treated front‐line with IST in Saint‐Louis Hospital. The cumulative incidence of response was lower in adults compared with AYA (subdistribution hazard ratio [ SHR ] = 0·38, 95% confidence interval [ CI ] [0·96–1·00], P  =   0·008), but no difference was observed between children and AYA ( SHR  = 0·84, 95% CI [0·96–1·00], P  =   0·56), with a 6 months cumulative incidence of partial response of 44·8% in children, 62·5% in AYA and 21·7% in adults. The 5‐year failure‐free survival was 48·4%, without impact of age, with a 5‐year relapse rate of 20·7%. With a median follow‐up of 5·4 years, the 5‐year overall survival was 86·5%, without significant difference between children and AYA overall survival (hazard ratio [ HR ] 1·51, 95% CI [0·25–9·02], P  =   0·66), while adults displayed poorer survival than AYA ( HR 4·98, 95% CI [1·00–24·73], P  =   0·049). This study confirms that age is a prognostic factor in AA patients treated with IST . However, AYA patients have a similar outcome to children in terms of response rate and survival.