Regional Market Competition and the Use of Immediate Breast Reconstruction After Mastectomy

Abstract

Background: Prior work has shown that the competitiveness of the market in which hospitals operate is associated with use of surgical procedures. This study examined the association between regional market competition and use of breast reconstruction for women with breast cancer and ductal carcinoma in situ undergoing mastectomy. Methods: Women who underwent mastectomy from 2010 to 2011 recorded in the National Inpatient Sample were selected. The competitive market environment for each hospital in which patients were treated was estimated using the Herfindahl–Hirschman Index. Multivariable models were developed to examine the association between regional market competition and breast reconstruction, with adjustment for other clinical, demographic, and structural variables. Results: Immediate breast reconstruction was performed for 9902 (45%) of 22,011 women. The rate of immediate breast reconstruction was 34.5% at hospitals in non-competitive markets, 49% at hospitals in moderately competitive markets, and 56.4% at hospitals in highly competitive markets (P < 0.0001). In a multivariable model, women in moderately competitive markets were 24% (risk ratio [RR] 1.24; 95% confidence interval [CI] 1.10–1.41) more likely to undergo immediate breast reconstruction than women in noncompetitive markets, whereas those in competitive markets were 25% (RR 1.25; 95% CI 1.11–1.41) more likely to have reconstruction. Later year of treatment, higher census tract income level, and residence in an urban area were associated with an increased likelihood of reconstruction (P < 0.05 for all). In contrast, older age, non-white race, and non-commercial insurance were associated with a lower likelihood of reconstruction (P < 0.05 for all). Conclusion: Patients who undergo mastectomy at hospitals in competitive markets are more likely to undergo immediate breast reconstruction.