Prognosis and Overall Survival of Thalassemia Patients using Semi-Parametric Mixture Cure-Rate Model: a 30-Year Retrospective Cohort Study.

BACKGROUND

Understanding the determinants of long-term overall survival (OS) of thalassemia patients (TPs) is the mainstay of care.

METHODS

As a retrospective survey, we assessed the data of 769 TPs who had regular follow-up and blood transfusion for at least 30 years from 1990 - 2019. We utilized semi-parametric proportional hazards mixture cure-rate regression to discover the factors with a significant effect on short- and long-term OS separately.

RESULTS

The 25- and 30-year OS for the TPs were calculated to be 98.7% and 90.4%, respectively. Each five-year age escalation was associated with a 30% decrease in the probability of being short-term survivors (HR = 1.06, p = 0.047). Parental family relationship influenced both cured (OR = 3.00, p = 0.017) and uncured (HR = 0.50, p = 0.046) TPs. Moreover, the type of iron chelation drug, liver iron concentration, and normal EF results had a significant effect on long-term OS. Aging, parental consanguinity, liver and cardiac siderosis, higher ferritin levels, and low hemoglobin level were associated with poorer prognosis in TPs.

CONCLUSIONS

However, deferoxamine followed by multiple drugs as iron chelation, severe liver siderosis, and abnormal EF declined the probability of long-term OS among TPs. This can be considered by health policy decision-makers to enforce the screening program more strictly.