Disparities in real-world treatment patterns of hypomethylating agents among patients with MDS in the United States

Compared with data from clinical trials, US population-level data show decreased effectiveness of hypomethylating agents (HMAs) in patients with myelodysplastic syndromes (MDS). We sought to identify factors associated with patterns of HMA use. In this retrospective cohort study, we identified 49 514 individuals aged ≥65 years with incident MDS during the years 2012 to 2013 using the 2011 to 2014 Medicare claims data set. We collected data on demographics, clinical characteristics, disease severity, and area-level socioeconomic measures. Multivariable logistic regression analysis was used to evaluate factors associated with receipt of HMA and duration of HMA therapy. A total of 7935 patients (16.1%) received HMAs. In adjusted analyses, the oldest age cohort (patients aged ≥85 years) had lower odds of receiving HMAs than their younger counterparts (aged 65-74 years; adjusted odds ratio [aOR], 0.41; 95% confidence interval [CI], 0.38-0.44). Females and Black patients had significantly lower odds than males and White patients to receive HMA (aOR, 0.81 [95% CI, 0.77-0.86] for females; aOR, 0.70 [95% CI, 0.62-0.8] for Blacks patients). In HMA recipients, factors associated with lower odds of receiving ≥4 cycles of HMAs included patients treated with decitabine (aOR, 0.7; 95% CI, 0.62-0.78), having 2 to 3 cytopenias (aOR, 0.69; 95% CI, 0.61-0.78), being nursing home residents (aOR, 0.64; 95% CI, 0.46-0.90), and having high frailty (aOR, 0.50; 95% CI, 0.34-0.75). We identified age-, sex-, and race-related disparities in receipt of HMAs, favoring younger, White males. The duration of therapy in HMA-treated patients in routine clinical practice showed wide divergence from recommended clinical guidelines.