Clinical Phenotype and Response to Different Lines of Therapy in Elderly with Immune Thrombocytopenia: A Retrospective Study

PURPOSE: Insufficient knowledge of primary immune thrombocytopenia purpura (ITP) in the elderly, together with a lack of clinical trial data, has resulted in wide variation in treatments. Here, we present a study focused on clinical characteristics of ITP in older subjects at diagnosis integrated with the subsequent course of the disease and treatment history. METHODS: In a retrospective monoinstitutional study, we evaluated >65-year-old patients with primary ITP. Clinical characteristics at the time of diagnosis were described and analyzed. We aimed to delineate whether subsequent lines of therapy influenced the number of relapses. In addition to initial regimens, we reported subsequent treatments and the impact on relapse trends. RESULTS: A total of 50 patients (56% males, mean age 78 years) were included. With regard to clinical variables at diagnosis, statistical significance was found for Eastern Cooperative Oncology Group performance status 1 (46% of patients, p<0.0001), presence of three comorbidities (36% of patients, p<0.0001), World Health Organization grade 0 bleeding (46%, p=0.0001), and World Health Organization grade 1 bleeding (42%, p=0.0009). For bleeding sites, the most frequent were skin or mucosa (40%, p=0.0477). A decrease in platelet count was correlated with moderate or severe bleeding (ρ=−0.52, p=0.0001) and viscera or skin/mucosa + viscera site (ρ=−0.50, p=0.0002). Finally, a decreasing number of patients required treatment from first-line therapy to sixth (p<0.0001). Relapse was most frequent before second-line therapy (54%, p<0.0001) and less frequent before fivth and sixth (4%, p=0.0072; 2%, p=0.0027). CONCLUSION: ITP in older age poses considerable challenges, so specific management strategies should be considered to optimize outcomes. Our findings provide evidence of an inverse relationship between lines of therapy and timing of relapses. This study does not exclude the possibility that agents used after first-line therapy may have an impact on the response and modify the unfavorable course of ITP.