How does active therapy (AT) timing impact transfusion dependence (TD) in MDS?
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Early AT initiation was associated with more transfusion independence (TI).
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Fewer early initiators used erythropoietin-stimulating agents before gaining RBC-TI.
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RBC-TI was more frequent in patients who met minimum therapy exposure.
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Higher rates of RBC-TI were associated with less time between TD and AT initiation.
Abstract
Myelodysplastic syndromes (MDS) are characterized by ineffective hematopoiesis resulting in refractory cytopenias. Red blood cell (RBC) transfusions can improve anemia; however, prolonged transfusion dependence (TD) is associated with increased morbidity and mortality. Disease-modifying therapy (DMT) for MDS can reduce transfusion requirements, although the optimum timing of DMT initiation is unclear. This retrospective study analyzed linked SEER registry and Medicare claims (2006–2012) to estimate the impact of DMT-initiation (azacitidine, decitabine, or lenalidomide) timing (≤ 3 vs. > 3 months from start of TD) on the likelihood of achieving transfusion independence (TI) among 508 TD patients with MDS. Mean time to DMT was 28 days for early initiators (n = 351) and 187 days for late initiators (n = 157). Fewer early initiators used erythropoiesis-stimulating agents before achieving TI versus late initiators (61.5% vs. 73.9%; P = 0.007). In multivariate analyses, early DMT initiation predicted TI achievement (HR, 1.69; P < 0.001); patients who met minimum active therapy-exposure requirements were more likely to achieve TI (HR, 2.12; P < 0.001). Higher rates of TI were associated with reduced time between onset of TD and DMT initiation. Similarly, patients meeting the minimum treatment-exposure threshold had higher TI rates.
Abbreviations
AML
acute myeloid leukemia
CI
confidence interval
CPT
Current Procedural Terminology
DMT
disease-modifying therapy
ESA
erythropoiesis-stimulating agent
FDA
Food and Drug Administration
HCPCS
Healthcare Common Procedure Coding System
HMA
hypomethylating agent
HR
hazard ratio
ICD-9-CM
International Classification of Diseases, Ninth Revision, Clinical Modification
ICD-O-3
International Classification of Diseases for Oncology, Third Edition
IPSS-R
Revised International Prognostic Scoring System
MDS
myelodysplastic syndromes
MDS-NOS
myelodysplastic syndromes, not otherwise specified
PPY
per patient-year
RA
refractory anemia
RAEB
refractory anemia with excess blasts
RAEB
t-refractory anemia with excess blasts in transformation