Acute graft versus host disease 1976-2020: reduced incidence and predictive factors.

We studied the incidence of acute graft versus host disease (GvHD) and its outcome in three consecutive time frames (year <2000; 2000-2010; >2010), in 3,120 patients allografted in two transplant Centers between 1976 and 2020. The median age increased over the three periods from 32 to 42 to 54 years ( p  < 0.00001). The median day of onset of GvHD in the three periods was day +14, day +16, and day +30, respectively ( p  < 0.0001). The cumulative incidence (CI) of GvHD grades II-IV in the three periods was 47, 24, and 16%, respectively ( p  < 0.00001). The CI of GvHD grades III-IV was 13, 5, and 4% ( p  < 0.001). In multivariate analysis, significant predictive factors for GvHD II-IV, on top of year of transplant, were anti-thymocyte globulin (ATG) (RR 0.67, p  > 0.001); post-transplant cyclophosphamide (PTCY) (RR 0.41, p  < 0.001), a family mismatched donor (RR 1.31, p  = 0.03) a matched unrelated donor (RR 2.1, p < 0.001), an unrelated mismatched donor (RR1.8, p  = 0.001), donor age above 40 years (RR 1.27, p  < 0.001), hematological malignancy-as compared to aplastic anemia (RR 2.3, p  < 0.001). When selecting only GvHD grade II, in a multivariate analysis, there was a significant reduction of transplant-related mortality (TRM) for patients grafted in 2001-2010 (RR 0.62, p  < 0.0001) and for patients grafted in 2011-2020 (RR 0.35, p  < 0.0001) as compared to grafts before the year 2000. A similar reduction in time was seen for patients with GvHD grades III-IV. The overall TRM in the three periods was 30, 22, and 16% ( p  < 0.0001) and survival was 47, 51, and 58% ( p  < 0.0001). Relapse risk was unchanged. In conclusion, we showed improved prevention of acute GvHD with time, together with a significant delay in the onset of the disease. Treatment of GvHD has also improved over time, as suggested by both reduced TRM and improved survival in more recent transplant periods.
Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
(Copyright © 2024 Di Francesco, Raiola, Dominietto, Di Grazia, Gualandi, Van Lint, Bregante, Chiusolo, Laurenti, Sora, Giammarco, Metafuni, Fresa, Sica, Angelucci and Bacigalupo.)