No Link Found Between Race, Doxorubicin-Related Cardiotoxicity in DLBCL

Although congestive heart failure (CHF) is common after doxorubicin chemotherapy for diffuse large B-cell lymphoma (DLBCL), a new study found no association between Black race and the onset of CHF.

“Doxorubicin is a highly effective antitumor antibiotic belonging to the anthracycline class of drugs, which have been used to treat millions of patients with a wide variety of malignancies,” study authors wrote. “A major problem with doxorubicin is its risk of cardiotoxicity, which can be acute or chronic and can range from asymptomatic left ventricular dysfunction to fulminant CHF.”

In this study, researchers used data from the Surveillance, Epidemiology, and End Results (SEER)-Medicare database to find 8,604 patients aged 66 years or older with DLBCL (3% Black). Patients with prior CHF were excluded.

The majority (77.3%) of patients had a history of hypertension. The rate of hypertension was significantly higher in Black patients compared with white patients (86.5% vs. 77.6%; P = 0.0006). About a third of patients had a history of diabetes (34.9%). Again, the rate of diabetes was significantly higher in Black patients than in white patients (47.1% vs. 34.5%; P<0.0001).

In adjusted models, Black race was associated with higher risk of incident CHF after receipt of doxorubicin and higher risk of incident CHF in the first year after receipt of doxorubicin. However, after adjustment for year of diagnosis, percent poverty, geographic group, history of hypertension, and history of diabetes, Black race no longer significantly associated with developing incident CHF.

The researchers stratified by cumulative doxorubicin dose and observed no significant differences in the incidence of CHF by race.

“Notably, our attempt to exclude patients with pre-existing heart failure may have controlled for racial differences in cardiac function that would affect subsequent outcomes,” the researchers noted. “Overall, our results suggest that attention to clinical risk factors that might correlate with race may be more useful than viewing race as an independent risk factor.”