Racial, Socioeconomic, and Geographic Disparities in the Receipt, Timing to Initiation, and Duration of Adjuvant Androgen Deprivation Therapy in Men with Prostate Cancer.

OBJECTIVE

This retrospective cohort study aims to examine the receipt, timing to initiation, and duration of androgen deprivation therapy (ADT) in men with prostate cancer by race/ethnicity, socioeconomic status, and geographic location.

METHODS

The study population are patients from Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database, who were 66 years or older and newly diagnosed with stage III and IV prostate cancer in 1992-2009 and underwent radiation therapy, where ADT was proven to be highly beneficial and its use was considered as most appropriate (n = 12,170). We use logistic regression to examine the receipt of ADT and linear regression to study factors associated with time to ADT initiation while controlling for baseline characteristics.

RESULTS

Overall, 77% of eligible patients received at least one form of ADT in combination with radiation therapy, of which 12% underwent orchiectomy and the rest received ADT, and 77.2% of non-Hispanic white and 80.7% of Hispanic patients received ADT compared to 73.8% of non-Hispanic black. After adjustment for demographic and tumor characteristics, black men and men of other races are less likely to receive ADT compared to white counterparts (OR = 0.64 and 0.74, respectively). The median time from cancer diagnosis to ADT initiation is 2 months. Once initiated, men received a median of seven drug injections. After controlling for covariates, race/ethnicity and geographic location (SEER areas) are associated with early initiation of therapy. White, Hispanic men and men living in the South initiate ADT earlier.

CONCLUSION

Significant racial disparities exist in the receipt and use of this highly beneficial therapy, and there are geographic variations in the utilization of this therapy.