Adjusted HRs and 95% CIs of HU use and types of SMs among 4023 patients with MPN. ∗Adjusted for MPN type, age at MPN diagnosis, sex, race, Elixhauser comorbidity score, marital status, zip code level median household income, eligibility for dual insurance, and SEER region. ∗∗PDC: proportion of days covered with HU prescriptions