Poor less likely to receive guideline-conforming care for breast cancer

Separate study shows poor socioeconomic status also increases risk for colorectal cancer.

Issue: February 10, 2012

Low socioeconomic status has long been known to be a negative predictor for outcomes in patients with cancer.

Now, results from separate studies show patients living in high-poverty areas were more likely to receive treatment that did not conform to published guidelines for breast cancer care and also were more likely to develop colorectal cancer compared with wealthier people.

In the first study, published online by the journal Cancer, Chyke A. Doubeni, MD, MPH, associate professor at the University of Massachusetts Medical School, and colleagues analyzed the association between individual and area-level socioeconomic status and the incidence of colorectal cancer overall and by tumor location. They reviewed data on 506,488 participants collected by the ongoing NIH-AARP Diet and Health Study.

The overall age- and sex-adjusted incidence rate for colorectal cancer was 16 per 10,000 person-years.

Doubeni and colleagues found that incidence of disease was inversely associated with levels of neighborhood socioeconomic status or personal educational achievement. Those with less than 12 years of education had a 42% greater risk of incidence for colorectal cancer (IRR=1.42; 95% CI, 1.29-1.56) compared with those with a postgraduate education. The association declined to an IRR of 1.19 (95% CI, 1.07-1.31) after researchers adjusted for behavioral factors and neighborhood socioeconomic status.

Risk for colorectal cancer was 31% more for those living in the poorest neighborhoods (IRR=1.31; 95% CI, 1.19-1.45) after adjustment for covariates such as age, gender and family history. The association was slightly weaker, although still significant, after researchers adjusted for behavioral covariates such as obesity, physical activity and smoking (IRR=1.16; 95% CI, 1.05-1.28).

“Many of the issues in risk of colorectal cancer are related to diet, and diet tends to be related to ethnic background and what types of food the community eats,” said Edith Mitchell, MD, PhD, clinical professor and associate director for diversity services at Thomas Jefferson University Hospitals in Philadelphia. “Diets that are high in fat and low in fiber contribute to risks. Aspirin and perhaps statins might reduce the risk. This is an excellent paper; however, there needs to be more research into the contributing environmental factors.”

Results of the second study appeared in the Journal of Clinical Oncology.

Xiao-Cheng Wu, MD, MPH, associate professor at Louisiana State University School of Public Health, and colleagues analyzed characteristics of patients with breast cancer to determine who received care that conformed to treatment guidelines. Care was evaluated by race, insurance status, socioeconomic status and hospital type.

Researchers reviewed data collected in the CDC’s Patterns of Care Study on 6,734 women who developed locoregional breast cancer in 2004. The study collected data on women in seven states who underwent chemotherapy or hormone therapy.

Overall, 35% of women received chemotherapy and 20% received hormone therapy that did not conform to established guidelines. More than four in five women lived in low-poverty areas and 51% were treated at non-Commission on Cancer hospitals.

For the 12% of patients who received non-conforming adjuvant chemotherapy, Wu and colleagues found that Medicaid insurance (OR=0.66; 95% CI, 0.50-0.86), residence in a high-poverty area (OR=0.77; 95% CI, 0.62-0.96) and treatment at non-Commission on Cancer hospitals (OR=0.69; 95% CI, 0.56-0.85) were all significant predictors.

“Approximately 70% of hospitals in the country are Commission members, and consequently, they have to adhere to certain standards such as following guidelines for therapy,” Mitchell said. “If care is received in non-Commission on Cancer hospitals, there is less likelihood that these guidelines would be adhered to. Part of the answer is addressing where patients receive care.”

Women who underwent hormone therapy, lived in high-poverty areas (OR=0.78; 95% CI, 0.64-0.96) or were treated at non-Commission on Cancer hospitals (OR=0.68; 95% CI, 0.55-0.83) were less likely to receive guideline-concordant therapy after adjustment for age, registry and clinical variables. Researchers found that differences observed among black women and residents in low-education areas were borderline significant. – by Jason Harris

For more information:

Doubeni CA. Cancer. 2012;doi:10.1002/cncr.26677.

Wu XC. J Clin Oncol. 2012;30:142-150.