Language, 6-mercaptopurine adherence, and relapse in children with acute lymphoblastic leukemia

Hispanic children with acute lymphoblastic leukemia (ALL) have lower 6-mercaptopurine (6MP) adherence and greater hazard of relapse compared with non-Hispanic White children. We examined the association between Spanish language and 6MP adherence, and hazard of relapse. 6MP adherence was measured electronically over a 6-month period. Participants were grouped by the language of demographic questionnaire completion: Non-Hispanic White-English Speaking (ES, n = 159), Hispanic-Spanish Speaking (Hispanic-SS, n = 59), and Hispanic-ES (n = 109). Hispanic-ES had significantly lower fitted median 6MP adherence compared with non-Hispanic White-ES participants (88.3%, 95% CI = 84.7% to 91.2% vs 95.0%, 95% CI = 93.6% to 96.2%, P < .001). There was no difference in fitted median 6MP adherence between Hispanic-ES and Hispanic-SS participants (88.3%, 95% CI = 84.1% to 91.5% vs 88.3%, 95% CI = 84.7% to 91.2%, P = .9) or adjusted hazard of relapse for Hispanic-SS participants (HR = 0.9, 95%CI = 0.3 to 2.4, P = .8). Spanish language use among Hispanic patients with ALL is not associated with lower 6MP adherence or greater relapse risk. Factors related to Hispanic ethnicity, apart from language, appear to influence adherence.