Abstract 990: Fundamental causes of colorectal cancer outcomes
Authors: Wang Andrew C. , Clouston Sean , Rubin Marcie , Colen Cynthia , Link Bruce 
Published: February 2011

Introduction Colorectal Cancer is a major cause of mortality with 16.2 people out of 10,000 dying in 2009. Treatments for colorectal cancer exist, with screening done by physicians at clinics and hospitals around the US. Social inequalities in Colorectal Cancer mortality are well studied. However, three theories have arisen that may help to explain why these inequalities have arisen. Fundamental Cause Theory posits that these inequalities arise due to unequal access to resources while this may work in part with differential access to healthcare, and finally differential Diffusion of Knowledge is posited to speed and slow uptake of new medical innovations.

Method Using administrative and census data from 2005, mortality rates per county in 3139 counties were stratified by socio-economic status (SES), volume of acute care hospitals (ACHs), volume of primary care physicians (PCPs), and groups of states considered slow to fast diffusion. We controlled for race and gender.

Preliminary Results There were 4,683 ACHs and 278,961 PCPs in the analyses. White male averaged 6.42 deaths per 10,000 people, White female at 4.27, Black male at 4.42, Black female at 3.24, Other male at 2.14, and Other female at 2.93. For hospital volume, the average mortality for counties with zero acute hospitals was 7.32 deaths per 10,000, one hospital was 6.20, two hospitals was 6.44, three to fifty hospitals was 5.62, and fifty-five to eighty-nine hospitals was 4.55. For counties with PCPs, areas with zero to four PCPs had an average mortality of 7.48 deaths per 10,000 people, five to thirteen PCPs was 6.06, fourteen to fifty PCPs was 6.17, and fifty-one to eight thousand eight hundred sixty three PCPs was 5.93. The average mortality for PCPs per 100,000 between 0-50 was 7.16 per 10,000, 51-100 was 6.10, 101-149 was 5.78, and more than 150 was 5.08. Counties with high SES and few hospitals had an average mortality of 6.64 per 10,000, where high SES and high volume of hospitals had 5.62, low SES and low volume had 6.19, and low SES and high volume had 7.34. States with slow diffusion had a mortality of 6.33 per 10,000, medium-slow had 6.13, medium-fast had 6.61, and fast had 5.86.

Conclusion In this study, we show varying support for each of the three major theories. Fundamental cause theory suggests that SES was correlated with lower mortality rates, but SES played the greatest role in counties with large numbers of hospitals and primary care physicians. Access to healthcare clearly mattered, with more hospitals and primary care physicians correlating to lower colorectal mortality rates. Finally, being in an area typified as quick diffusing was related to lower mortality. This study thus suggests that fundamental cause theory works in part through access to health care. There are long term implications for policy makers looking to reduce social inequalities in colorectal cancer mortality.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 990.