Variation by age in neutropenic complications among patients with cancer receiving chemotherapy
Background Age is among the most important risk factors for neutropenia-related hospitalization, but evidence is limited regarding the relative contributions of age and other risk factors.
Objective To explore the associations among patient age, other risk factors, and neutropenic complications in patients with cancer receiving myelosuppressive chemotherapy.
Methods This retrospective cohort study, which used a US commercial insurance claims database, included patients aged 40 years or older with non-Hodgkin lymphoma (NHL), breast cancer, or lung cancer who initiated chemotherapy between January 1, 2006 and March 31, 2010. The primary endpoint was the risk of neutropenia-related hospitalization during the
first chemotherapy course. We used cubic spline modeling to estimate the association between neutropenia-related hospitalization and age, adjusting for patient and treatment characteristics. Logistic regression analyses examined the effects of other risk factors.
Results A total of 15,638 patients were included (NHL, n = 2,506; breast cancer, n = 9,110; lung cancer, n = 4,022), mean age 56-66 years. Neutropenia-related hospitalization occurred in 8.7% of NHL patients, 4.2% of breast cancer patients, and 3.9% of lung cancer patients. The association between age and the risk of neutropenia-related hospitalization was stronger in NHL than in lung or breast cancer. Patient comorbidities and chemotherapy characteristics had considerable effects on risk of neutropenia-related hospitalization.
Limitations Disease stage and other clinical factors could not be identified from the claims data.
Conclusion In addition to age, oncologists should evaluate individual patient risk factors including patient comorbidities and type of chemotherapy regimen.