Abstract 2627: Socioeconomic status and utilization of major surgical procedures in the United States, Canada, and Australia
Authors: Pang Hilary , Chalmers Kelsey , Landon Bruce , Elshaug Adam , Matelski John , Ling Vicki , Krzyzanowska Monika K. , Kulkarni Girish , Erickson Bradley A. , Cram Peter 
Published: July 2021

Abstract
Purpose: This study aimed to compare the utilization rates of three organ resection surgeries, predominantly indicated for the treatment of cancer, in the US, Canada, and Australia, and compare rates between residents of lower- and higher-income neighborhoods.
Methods: We used population-based administrative data to identify all adults aged ≥18 years hospitalized for pancreatectomy (PX), radical prostatectomy (RP) and nephrectomy (NX) between 2011-2016 (New York, USA), 2011-2018 (Ontario, Canada), and 2013-2018 (New South Wales, Australia). We linked each patient's zip-code of residence to 2016 census data to ascertain neighborhood income. We compared utilization rates for each procedure in each jurisdiction in aggregate and by neighborhood income quintile. Primary outcomes were: 1) each jurisdictions' per-capita overall, age-, and sex-standardized utilization rates for each procedure; and 2) utilization rates amongst residents of lower- and higher-income neighborhoods.
Results: Sociodemographics were similar across jurisdictions; patients in New South Wales were older for all procedures. New York hospitals were significantly likelier to perform each of the three procedures compared to Ontario and New South Wales (all P&lt;0.001); New York and New South Wales hospitals tended to have lower volumes than Ontario hospitals. Overall utilization rate was highest in New York for NX (28.93 procedures per-100,000 per-year) while New South Wales had the highest utilization of PX (6.94) and RP (94.37); overall utilization of all three procedures was lowest in Ontario (PX 6.18; RP 49.24; NX 21.40; all P&lt;0.001). Utilization of PX and NX was significantly higher for men than women in all jurisdictions (all P&lt;0.05). Utilization of all three procedures increased until age 70-79, before declining at age ≥80 (all P&lt;0.001). With the exception of NX in Ontario, residents of lowest income neighborhoods (quintile 1 [Q1]) had lower surgical utilization rates than residents of highest income neighborhoods (quintile 5 [Q5]). The Q5-Q1 utilization rate difference was largest in New South Wales for PX and RP (Q5-Q1 PX +4.65 procedures per-100,000 per-year; RP +73.46; NX +6.23), largest in New York for NX and smallest for RP (PX +3.05; RP +19.70; NX +8.43) and smallest in Ontario for PX and NX (PX +1.15; RP +27.94; NX -1.10) (all P&lt;0.05).
Conclusions: Utilization rates of PX, RP, and NX were significantly higher in New York and New South Wales than in Ontario. Rich-poor surgical utilization differences were significantly larger in New York and New South Wales and significantly smaller in Ontario. These findings suggest that income-based disparities are larger in US and Australian jurisdictions than those Canadian, and highlight the possible trade-offs of equity and access in cancer care of different countries.
Citation Format: Hilary Pang, Kelsey Chalmers, Bruce Landon, Adam Elshaug, John Matelski, Vicki Ling, Monika K. Krzyzanowska, Girish Kulkarni, Bradley A. Erickson, Peter Cram. Socioeconomic status and utilization of major surgical procedures in the United States, Canada, and Australia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2627.