Patient registry data collected between 2000 and 2011 in Sweden reported 5-year survival of around 61% in all patients with AA.[9]Vaht K, Göransson M, Carlson K, et al. Incidence and outcome of acquired aplastic anemia: real-world data from patients diagnosed in Sweden from 2000-2011. Haematologica. 2017 Oct;102(10):1683-90.
http://www.haematologica.org/content/102/10/1683.long
http://www.ncbi.nlm.nih.gov/pubmed/28751565?tool=bestpractice.com
Prognosis for those who do not have severe AA is excellent, with survival >90%.[38]Marsh J, Schrezenmeier H, Marin P, et al. Prospective randomized multicenter study comparing cyclosporin alone versus the combination of antithymocyte globulin and cyclosporin for treatment of patients with nonsevere aplastic anemia: a report from the European Blood and Marrow Transplant (EBMT) Severe Aplastic Anaemia Working Party. Blood. 1999 Apr 1;93(7):2191-5.
http://bloodjournal.org/content/93/7/2191.full
http://www.ncbi.nlm.nih.gov/pubmed/10090926?tool=bestpractice.com
Some spontaneously remit; others may live many years without progression of disease.
The prognosis of patients with severe or very severe AA has markedly improved over the last 30 years. The 5-year survival with immunosuppressive therapy, using horse anti-thymocyte globulin (ATG) plus cyclosporine, is around 75% to 80%, but lower with rabbit ATG.[9]Vaht K, Göransson M, Carlson K, et al. Incidence and outcome of acquired aplastic anemia: real-world data from patients diagnosed in Sweden from 2000-2011. Haematologica. 2017 Oct;102(10):1683-90.
http://www.haematologica.org/content/102/10/1683.long
http://www.ncbi.nlm.nih.gov/pubmed/28751565?tool=bestpractice.com
[53]Scheinberg P, Nunez O, Weinstein B, et al. Horse versus rabbit antithymocyte globulin in acquired aplastic anemia. N Engl J Med. 2011 Aug 4;365(5):430-8.
https://www.nejm.org/doi/10.1056/NEJMoa1103975
http://www.ncbi.nlm.nih.gov/pubmed/21812672?tool=bestpractice.com
However, survival rate may be age-dependent. In one study, younger patients (ages 19 to 39 years) treated with immunosuppressive therapy had a significantly higher 5-year survival than older patients (ages ≥60 years) treated with immunosuppressive therapy (90% vs. 52%, respectively).[9]Vaht K, Göransson M, Carlson K, et al. Incidence and outcome of acquired aplastic anemia: real-world data from patients diagnosed in Sweden from 2000-2011. Haematologica. 2017 Oct;102(10):1683-90.
http://www.haematologica.org/content/102/10/1683.long
http://www.ncbi.nlm.nih.gov/pubmed/28751565?tool=bestpractice.com
With stem cell transplant (SCT), young patients with a matched related donor have a probability of long-term survival >80%; for older patients the prognosis is not quite as good. Outcomes after matched unrelated donor SCT have improved significantly, such that overall survival is similar to matched related donor SCT when using ATG-based conditioning regimens, although with a higher risk of graft versus host disease (GVHD).[73]Bacigalupo A, Socié G, Hamladji RM, et al. Current outcome of HLA identical sibling versus unrelated donor transplants in severe aplastic anemia: an EBMT analysis. Haematologica. 2015 May;100(5):696-702.
http://www.haematologica.org/content/100/5/696.long
http://www.ncbi.nlm.nih.gov/pubmed/25616576?tool=bestpractice.com
In contrast, the use of alemtuzumab-based conditioning is associated with a lower risk of GVHD in the setting of unrelated donor SCT.[74]Grimaldi F, Potter V, Perez-Abellan P, et al. Mixed T cell chimerism after allogeneic hematopoietic stem cell transplantation for severe aplastic anemia using an alemtuzumab-containing regimen is shaped by persistence of recipient CD8 T cells. Biol Blood Marrow Transplant. 2017 Feb;23(2):293-9.
https://www.sciencedirect.com/science/article/pii/S1083879116304621
http://www.ncbi.nlm.nih.gov/pubmed/27816648?tool=bestpractice.com
The impact of best supportive care is extremely important for patients in all stages of the disease. Developments in supportive care have led to a reduction in infection-related deaths and thereby improved the survival of refractory patients.[75]Valdez JM, Scheinberg P, Nunez O, et al. Decreased infection-related mortality and improved survival in severe aplastic anemia in the past two decades. Clin Infect Dis. 2011 Mar 15;52(6):726-35.
http://www.ncbi.nlm.nih.gov/pubmed/21367725?tool=bestpractice.com