DOXORUBICIN CARDIOTOXICITY IN AFRICAN AMERICANS: RESULTS

Out of 120 eligible patients receiving doxorubicin combination therapy at Howard during the study period, 100 patients were evaluable, all of whom were African American (65% women, 35% men, median age 46 years, range 32-84 years). Fifteen patients had hypertension, and 10 were diabetics. None of the patients had history of CHF or coronary artery disease before the institution of chemotherapy. Patients received multiple doses of doxorubicin (range 264-580 mg/m2 with median of 374 mg/m2) with the final echocardiographic assessment at a median of 1.3 years (Table 1). The fractions with cardiotoxicity in our study versus those from Lefrak’s study were 25% versus 18% at 551-600 mg/m2,10% versus 4% at 501-550 mg/m2, 4% versus 1% at 451-500 mg/m2, and 0% versus <1% at <450 mg/m2 cumulative dose of doxorubicin. Lumping all levels of exposure, African Americans in our study had a higher rate of cardiotoxicity after doxorubicin (7/100 cases) than the study population in Lefrak’s study (10/399), a difference statistically significant at p<0.027 with an odds ratio of 2.93 (95% confidence interval from 0.98 to 8.6). Gender did not appear to be a significant risk factor within our case series. There were 65 women out of 100 patients. Five out of seven patients who developed cardiotoxicity (p<0.3 for the chi-square test) were women. In our case series, 59% of treatments with doxorubicin were of which five patients developed cardiotoxicity, 36% for lymphoma of which two developed cardiotoxicity, and 5% for other malignancies, with none exhibiting cardiotoxicity.

Table 1. Clinical characteristics of Seven Patients

Patient

Age (Years)/

Type of Cancer/

Radiation
Number

Gender

Comorbid Conditions

1

54/ F

Breast cancer/hypertension

Y
2

48/F

Breast cancer

Y
со

56/F

Breast cancer/arthritis

N
4

82/M

Non-Hodgkin’s lymphoma/hypertension

N
5

69/M

Non-Hodgkln’s lymphoma

N
6

34/F

Breast cancer

N
7

46/F

Breast cancer/asthma drug

Y