Abstract: PD32-04
Sources of Funding: American Cancer Society (MSRG-15-103-01-CHPHS to MJR), AUA/Urology Care Foundation Rising Stars in Urology Research Program

Introduction

Despite marked growth in Accountable Care Organizations (ACOs), little is known about either the magnitude of surgeon engagement or key drivers of surgeon engagement in early ACO programs. We aimed to characterize the landscape of surgeon engagement in early ACOs and identify specialty-, organization-, and market-factors associated with early ACO participation.

Methods

Using data from SK&A, a commercial research firm, we evaluated independent, group, and integrated U.S. surgical practices, performing a cross-sectional analysis of 2015 ACO enrollment among 125,425 U.S. surgeons. We fit a multivariable logistic regression model to evaluate associations between ACO affiliation, surgical specialty, and organizational structure while adjusting for surgeon characteristics.

Results

Of 125,425 U.S. surgeons, 27,956 (22.3%) reported enrollment in at least 1 ACO program in 2015. We identified significant heterogeneity in the proportion of ACO-enrolled surgeons by surgical specialty, with trauma and transplant reporting the highest magnitude of ACO enrollment, (36% for both) and plastic surgeons reported the lowest magnitude of ACO enrollment (12.9%) followed by ophthalmology (16.0%) and hand (18.6%). 22.8% of urologists reported at least 1 ACO contract. Practice organization was strongly associated with ACO enrollment, with surgeons in group practices and integrated health systems had higher odds of ACO affiliation relative to those practicing independently (aOR 1.57, 95% CI 1.50, 1.64; aOR 4.87, 95% CI 4.68, 5.07, respectively). We observed a statistically significant interaction (p<0.001) between surgical specialty and practice organization. Model-derived predicted probabilities revealed that, within each specialty, surgeons in an integrated health system had the highest predicted probabilities of ACO affiliation while those practicing in groups had smaller predicted probabilities and those practicing independently generally had the lowest. This pattern was largely consistent across surgical specialties.

Conclusions

We observed considerable variation in ACO enrollment among U.S. surgeons. Observed variation appears to be largely mediated by differences in practice organization, with surgeons practicing in integrated health systems more likely to engage in ACO contracts than those in independent practice.

Funding

American Cancer Society (MSRG-15-103-01-CHPHS to MJR), AUA/Urology Care Foundation Rising Stars in Urology Research Program