Effects of Education and Income on Treatment and Outcome in Patients With Acute Myeloid Leukemia in a Tax-Supported Health Care System: A National Population-Based Cohort Study

Abstract

Purpose Previous US studies have shown that socioeconomic status (SES) affects survival in acute myeloid leukemia (AML). However, no large study has investigated the association between education or income and clinical characteristics, treatment, and outcome in AML. Methods To investigate the effects of education and income in a tax-supported health care system, we conducted a population-based study using individual-level SES and clinical data on all Danish patients with AML (2000 to 2014). We compared treatment intensity, allogeneic transplantation, and response rates by education and income level using logistic regression (odds ratios). We used Cox regression (hazard ratios [HRs]) to compare survival, adjusting for age, sex, SES, and clinical prognostic markers. Results Of 2,992 patients, 1,588 (53.1%) received intensive chemotherapy. Compared with low-education patients, highly educated patients more often received allogeneic transplantation (16.3% v 8.7%). In intensively treated patients younger than 60 years of age, increased mortality was observed in those with lower and medium education (1-year survival, 66.7%; adjusted HR, 1.47; 95% CI, 1.11 to 1.93; and 1-year survival, 67.6%; adjusted HR, 1.55; CI, 1.21 to 1.98, respectively) compared with higher education (1-year survival, 76.9%). Over the study period, 5-year survival improvements were limited to high-education patients (from 39% to 58%), increasing the survival gap between groups. In older patients, low-education patients received less intensive therapy (30% v 48%; adjusted odds ratio, 0.65; CI, 0.44 to 0.98) compared with high-education patients; however, remission rates and survival were not affected in those intensively treated. Income was not associated with therapy intensity, likelihood of complete remission, or survival (high income: adjusted HR, 1.0; medium income: adjusted HR, 0.96; 95% CI, 0.82 to 1.12; low income: adjusted HR, 1.06; CI, .88 to 1.27). Conclusion In a universal health care system, education level, but not income, affects transplantation rates and survival in younger patients with AML. Importantly, recent survival improvement has exclusively benefitted highly educated patients.