Medical Costs of Adverse Events Associated with Patients Diagnosed with Chronic Myeloid Leukemia.

Tyrosine kinase inhibitors (eg, imatinib) have revolutionized the treatment of chronic myeloid leukemia (CML). However, new therapies developed to treat imatinib-resistant CML may be associated with undesirable side effects. The purpose of this analysis was to quantify the medical costs for significant adverse events (AE) associated with patients diagnosed with CML. De-identified medical and pharmacy claims data from 5 million individuals covered by 31 large U.S. corporations between 1/98 and 1/05 were used. CML patients were identified as patients < 65 years of age with ≥ 2 CML diagnosis claims (ICD-9 205.1). The study period spanned from the first CML claim until the earliest of end of enrollment date or the defined end of study (1/05). The following AE groups were identified during the study period for analysis, and their costs were tabulated on a per patient per visit basis: myelosuppression (anemia, neutropenia, thrombocytopenia, administration of growth factors, or blood or platelet transfusions), fluid retention (pleural or pericardial effusion, fluid overload, pulmonary or peripheral edema, thoracentesis, pericardiocentesis), gastrointestinal (GI) bleeding, central nervous system (CNS) hemorrhage, cardiac dysfunction/congestive heart failure (CHF), diarrhea, nausea and vomiting, and rash. Among the 357 identified CML patients, the proportion of patients presented with the identified AE groups was 42.3% for myelosuppression, 17.4% fluid retention, 1.7% GI bleeding, 1.4% CNS hemorrhage, 1.5% heart failure, 3.4% diarrhea, 9.8% nausea and vomiting, and 2.8% rash. Table 1 displays the frequency of outpatient and inpatient visits associated with the AE groups, the mean medical costs per visit, and the mean hospital length of stay. The results show that these AEs incurred significant medical resource utilization and required repeated visits. The medical costs of CML-associated AEs were high, with myelosuppression and CNS hemorrhage among the most expensive costing over $2,000 per outpatient visit and over $10,000 per inpatient visit. As the treatment options for CML expand, it is crucial to formulate the treatment strategy based on both efficacy and toxicities associated with therapies to achieve optimal clinical and economic outcomes.