Racial disparities observed in treatment of multiple myeloma
Black and Hispanic patients with multiple myeloma appeared more likely to initiate treatment with a novel therapy significantly later than their white counterparts, according to study results published in Blood Advances.
“[Although] our study showed that median OS was similar across all groups, comparison with previous research suggests the survival rate for black patients in particular has decreased,” Sikander Ailawadhi, MD, associate professor in the division of hematology/oncology at Mayo Clinic in Jacksonville, Florida, told HemOnc Today. “The delay in treatment initiation may have inhibited black patients’ normally better survival outcome, but this would have to be confirmed in another study. Indeed, other studies show that if differences in access to treatment are overcome, such as in the Veterans Affairs system, outcomes for black patients may be superior to those among whites.”
Differences in treatment patterns and patient outcomes based on race/ethnicity have not been studied extensively in the setting of novel therapeutics for multiple myeloma.
To assess these disparities, researchers pooled data from the SEER-Medicare database on 3,504 white (mean age, 75.8 years; 52.3% men), 858 black (mean age, 71.8 years; 40.6% men) and 468 Hispanic (mean age, 72.7 years; 52.4% men) patients with multiple myeloma. Compared with the white cohort, the black and Hispanic cohorts included smaller proportions of married patients and larger proportions of patients with a lower socioeconomic status. White patients had a lower mean Charlson Comorbidity Index score (2.2) than black patients (3.2) and Hispanic patients (2.7; P < .001 for both).
Study results showed an average length of time from diagnosis to treatment initiation of 2.7 months for white patients, 4.6 months for Hispanic patients and 5.2 months for black patients (P < .05). After adjusting for baseline characteristics, such as age, gender and marital status, the average length of time to treatment initiation remained higher for white patients compared with black patients (HR = 0.8; P < .05) and Hispanic patients (HR = 0.9; P < .05).
“Although we had noted in other analyses that minorities may not receive timely access to all therapeutic agents compared with whites, our current analysis showed a much more uniform trend for this discrepancy,” Ailawadhi told HemOnc Today. “Minorities were noted to not be introduced to treatment early enough to derive adequate clinical gains as compared with white patients.”
Delays in treatment for multiple myeloma can result in organ damage, kidney dysfunction, anemia and infections, among other conditions. Novel immunomodulatory and proteasome agents have improved survival substantially, and autologous hematopoietic stem cell transplantation remains the standard of care for eligible patients, conferring a greater benefit when conducted earlier in treatment.
An analysis of rates of HSCT within 1 year of diagnosis from 2007 to 2009, 2010 to 2011 and 2012 to 2013 showed an increasing trend among white patients (3.6%, 7.2%, 9.7%; P < .05) and black patients (2.5%, 2.2%, 9.3%; P < .05), but not among Hispanic patients (1.6%, 6.1%, 1.9%).
Median OS was 2.6 years among white patients, 2.5 years among black patients and 2.8 years among Hispanic patients.
Black patients had significantly longer median multiple myeloma-specific survival (5.4 years) than white patients (4.5 years; P < .05). Disease-specific survival among whites appeared similar to that of Hispanics (4.9 years).
After adjusting for other factors, the risk for multiple myeloma-associated mortality remained significantly lower for black patients than for white patients (adjusted HR = 0.8; P < .05). Moreover, the 3-month ED visit rate appeared significantly higher among black vs. white patients (31.2% vs. 23.8%; adjusted HR =1.2; P < .01).
An analysis of health care costs showed mean unadjusted all-cause total monthly costs of $12,462 for white patients, $13,611 for black patients, and $15,149 for Hispanic patients. Mean unadjusted multiple myeloma-associated monthly costs were $4,620 among whites, $4,384 among blacks and $5,568 among Hispanics.
“[Although] future research is needed to investigate possible causes for the observed racial disparities, we hope that understanding and addressing them will lead to more equitable health care, cost and outcome profiles for all [patients with] multiple myeloma, regardless of race or ethnicity,” Ailawadhi said in a press release. – by Jennifer Southall
For more information:
Sikander Ailawadhi, MD, can be reached at Mayo Clinic Florida, 4500 San Pablo Road, Jacksonville, FL 32224; email: email@example.com.
Disclosures: Ailawadhi reports a consultant role with Celgene Corp.; honoraria from Amgen, Janssen and Takeda; and research funding from Pharmacyclics. Please see the study for all other authors’ relevant financial disclosures.