Table 4.
Mediation analysis of racial/ethnic disparities in leukemia death
| N | Unmediated model | Mediated model | Rescaled coefficients | |||||
|---|---|---|---|---|---|---|---|---|
| HR | (95% CI) | HR | (95% CI) | %Change* | %Change† | P‡ | ||
| Baseline | Census tract structural racism | Mediation proportion estimates | ||||||
| Race/ethnicity | ||||||||
| NH White | 482 | 1.0 | 1.0 | |||||
| NH Black | 120 | 1.61 | (1.15, 2.26) | 1.04 | (0.65, 1.66) | 94% | 83% | .006 |
| Hispanic | 117 | 1.20 | (0.83, 1.72) | 0.96 | (0.65, 1.43) | 120% | 100% | .006 |
| Other | 79 | 1.27 | (0.83, 1.92) | 1.24 | (0.82, 1.89) | 9% | None | |
| Race/ethnicity | Tumor biology | |||||||
| NH White | 477 | 1.0 | 1.0 | |||||
| NH Black | 115 | 1.51 | (1.07, 2.12) | 1.42 | (1.01, 2.00) | 17% | 9% | .15 |
| Hispanic | 114 | 1.23 | (0.86, 1.77) | 1.27 | (0.88, 1.83) | −15% | None | |
| Other | 72 | 1.28 | (0.84, 1.96) | 1.25 | (0.82, 1.92) | 10% | None | |
| Race/ethnicity | Health care access | |||||||
| NH White | 487 | 1.0 | 1.0 | |||||
| NH Black | 125 | 1.63 | (1.17, 2.26) | 1.66 | (1.18, 2.32) | −5% | None | |
| Hispanic | 114 | 1.27 | (0.89, 1.81) | 1.21 | (0.84, 1.75) | 21% | 22% | .09 |
| Other | 82 | 1.33 | (0.89, 2.00) | 1.33 | (0.88, 1.99) | 2% | None | |
| Race/ethnicity | Treatment | |||||||
| NH White | 479 | 1.0 | 1.0 | |||||
| NH Black | 118 | 1.67 | (1.19, 2.34) | 1.34 | (0.95, 1.90) | 49% | 47% | <.0001 |
| Hispanic | 113 | 1.25 | (0.86, 1.79) | 1.07 | (0.74, 1.54) | 73% | 72% | .002 |
| Other | 78 | 1.33 | (0.88, 2.02) | 1.32 | (0.86, 2.03) | 4% | None | |
| Race/ethnicity | Comorbidity | |||||||
| NH White | 356 | 1.0 | 1.0 | |||||
| NH Black | 107 | 1.53 | (1.08, 2.17) | 1.57 | (1.10, 2.23) | None | None | |
| Hispanic | 85 | 1.11 | (0.74, 1.67) | 1.07 | (0.71, 1.62) | 35% | 49% | .11 |
| Other | 51 | 0.84 | (0.49, 1.45) | 0.86 | (0.50, 1.49) | 13% | None | |
| Race/ethnicity | ICU admission at induction (N = 573) | |||||||
| NH White | 315 | 1.0 | 1.0 | |||||
| NH Black | 85 | 1.34 | (0.85, 2.09) | 1.22 | (0.78, 1.92) | 34% | 26% | .01 |
| Hispanic | 88 | 1.23 | (0.77, 1.97) | 1.20 | (0.75, 1.92) | 13% | 24% | .04 |
| Other | 54 | 1.30 | (0.76, 2.21) | 1.18 | (0.69, 2.02) | 39% | 48% | .001 |
Mediation proportion estimates <10% are suppressed (reported as “None”), and P > .20 is suppressed. All models are adjusted for age, sex, and diagnosing hospital.
*
%Change in the excess hazard ratio for the disparity in leukemia death before and after controlling for potential mediation.
†
Proportionate reduction in the rescaled coefficients before vs after controlling for potential mediation.
‡
P value for the difference in rescaled coefficients before vs after controlling for potential mediation.