Date Published: April 6, 2017
Publisher: Public Library of Science
Author(s): Brice Jabo, John W. Morgan, Maria Elena Martinez, Mark Ghamsary, Matthew J. Wieduwilt, Senthilnathan Palaniyandi.
Identifying sociodemographic disparities in chemotherapy and hematopoietic cell transplantation (HCT) utilization for acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) may improve survival for underserved populations. In this study, we incorporate neighborhood socioeconomic status (nSES), marital status, and distance from transplant center with previously studied factors to provide a comprehensive analysis of sociodemographic factors influencing treatments for ALL and AML.
Using the California Cancer Registry, we performed a retrospective, population-based study of patients ≥15 years old with ALL (n = 3,221) or AML (n = 10,029) from 2003 through 2012. The effect of age, sex, race/ethnicity, marital status, nSES, and distance from nearest transplant center on receiving no treatment, chemotherapy alone, or chemotherapy then HCT was analyzed.
No treatment, chemotherapy alone, or chemotherapy then HCT were received by 11%, 75%, and 14% of ALL patients and 36%, 53%, and 11% of AML patients, respectively. For ALL patients ≥60 years old, HCT utilization increased from 5% in 2005 to 9% in 2012 (p = 0.03). For AML patients ≥60 years old, chemotherapy utilization increased from 39% to 58% (p<0.001) and HCT utilization from 5% to 9% from 2005 to 2012 (p<0.001). Covariate-adjusted analysis revealed decreasing relative risk (RR) of chemotherapy with increasing age for both ALL and AML (trend p <0.001). Relative to non-Hispanic whites, lower HCT utilization occurred in Hispanic [ALL, RR = 0.80 (95% CI = 0.65–0.98); AML, RR = 0.86 (95% CI = 0.75–0.99)] and non-Hispanic black patients [ALL, RR = 0.40 (95% CI = 0.18–0.89); AML, RR = 0.60 (95% CI = 0.44–0.83)]. Compared to married patients, never married patients had a lower RR of receiving chemotherapy [ALL, RR = 0.96 (95% CI = 0.92–0.99); AML, RR = 0.94 (95% CI = 0.90–0.98)] or HCT [ALL, RR = 0.58 (95% CI = 0.47–0.71); AML, RR = 0.80 (95% CI = 0.70–0.90)]. Lower nSES quintiles predicted lower chemotherapy and HCT utilization for both ALL and AML (trend p <0.001). Older age, lower nSES, and being unmarried predicted lower utilization of chemotherapy and HCT among ALL and AML patients whereas having Hispanic or black race/ethnicity predicted lower rates of HCT. Addressing these disparities may increase utilization of curative therapies in underserved acute leukemia populations.
Acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) are potentially curable malignancies using multi-agent chemotherapy with or without hematopoietic cell transplantation (HCT). For most patients with AML, and many with ALL, chemotherapy alone is insufficient to produce a high likelihood of long-term remission and allogeneic HCT offers the best hope for cure [1–7]. Delays in initial chemotherapy and administration of HCT can adversely affect outcomes by increasing the risk of complications and relapse . Additionally, lack of access to allogeneic HCT deprives some patients of this potentially curative therapy [9,10]. Identifying actionable sociodemographic factors that predict lack of access to chemotherapy and allogeneic HCT could extend these curative therapies to more patients diagnosed with acute leukemia.
In addition to the roles of age, sex, and race as predictors of acute leukemia treatment identified in other studies, findings reported here also assessed a multidimensional nSES index, marital status, and distance between usual place of residence and nearest transplant center. Our findings are consistent with previous studies reporting lower HCT utilization among Hispanic and non-Hispanic black acute leukemia patients [10,15,16]. Additional findings reveal that increasing SES quintile categories independently predicted increased chemotherapy and HCT utilization among both ALL and AML patients, with substantially lower use of HCT among unmarried patients with low nSES.
Our findings reveal that, in addition to age, nSES and marital status were independent and dose-related predictors of chemotherapy and HCT utilization acute leukemia patients. Unlike findings from other researchers, race/ethnicity and sex did not represent barriers to chemotherapy among acute leukemia patients in the diverse and contemporary California population. Although Hispanic and non-Hispanic black race/ethnicity were not independent predictors of chemotherapy among acute leukemia patients, Hispanic and non-Hispanic black race/ethnicity persisted as independent negative predictors of HCT utilization. Married patients had higher utilization of both chemotherapy and HCT relative to unmarried patients when adjusted for other factors. These findings support a shift from research and interventions addressing chiefly racial and ethnic barriers to care for acute leukemia to also addressing barriers raised by socioeconomic disparities, advanced age, and unmarried status. Better understanding and correction of specific actionable factors within each of these underserved populations should lead to more equitable and inclusive access to potentially curative chemotherapy and hematopoietic cell transplantation for ALL and AML patients.