Uncovering the Neighborhood Influence on Breast Cancer Mortality

Samilia Obeng-Gyasi, MD, MPH

According to a recent investigation conducted by researchers at The Ohio State University Comprehensive Cancer Center, reduced neighborhood opportunity was linked with increased allostatic load, as well as heightened susceptibility to all-cause mortality among patients with breast cancer.¹ Environmental factors and allostatic load also interested to affect all-cause mortality outcomes.

This study sought to investigate the correlation between neighborhood opportunity, allostatic load, and breast cancer outcomes across a cohort of over 4000 patients. Enrollment was open to women aged 18 years and older who had newly diagnosed stage I to III breast cancer. Patients must have also received surgical treatment between January 1, 2012, and December 31, 2020, at a National Cancer Institute Comprehensive Cancer Center.

According to Samilia Obeng-Gyasi, MD, MPH, findings from the study showed that lower levels of neighborhood opportunity were linked with heightened allostatic load and increased all-cause mortality rates (adjusted OR, 1.21; 95% CI, 1.05-1.40). Using an adjusted analysis, the low Ohio Opportunity Index also correlated with greater risk of all-cause mortality (adjusted HR, 1.45; 95% CI, 1.11-1.89).

Further, those who exhibited a high allostatic load and lived in neighborhoods marked by adverse environmental factors, including limited walkability or pollution, faced elevated risks of all-cause mortality vs those residing in more favorable environments (adjusted HR, 1.96), while those in higher-opportunity environments did not (adjusted HR, 1.02; P =.02).

“We found that individuals who live in neighborhoods with low opportunity once again, operationalizing the opportunity as neighborhoods that are resource poor, are more likely to have a worse all-cause mortality, which is death from any cause, compared [with] patients who live in neighborhoods with a high opportunity,” explained Obeng-Gyasi, associate professor of surgery at The Ohio State University Wexner Medical Center, in an interview with Targeted Oncology^TM. “These findings are interesting in that we also looked at opportunity or neighborhood contextual factors within the context of allostatic load.”

In an interview, Obeng-Gyasi delved into the background and findings of this study assessing the correlation between neighborhood opportunity, allostatic load, and all-cause mortality among patients with breast cancer.

Breast Cancer - Female Anatomy - pain concept: © peterschreiber.media - stock.adobe.com

Targeted Oncology: Would you give a brief overview of this study?

Obeng-Gyasi: In this study, we were interested in looking at neighborhood contextual factors, specifically looking at neighborhood opportunity. Neighborhood opportunity looks at local conditions and resources within a neighborhood and how they can be used to promote healthy development. We also looked at something called an allostatic load. Allostatic load can [be thought] of as a biological correlate for exposure distress. Our main outcome was overall mortality, so what we wanted to understand was, is there a relationship between a neighborhood opportunity, allostatic load, and overall mortality in patients who have breast cancer?

The study revealed an association between lower neighborhood opportunity and higher allostatic load. What are some of the potential mechanisms explaining this correlation?

What we are hypothesizing is that individuals who live in neighborhoods that are resource-poor face specific socio environmental stressors that can activate the stress response. This activates a stress response that can be measured by using biological correlates like allostatic load. Essentially, people who do not have a lot of resources face a lot of stress, and the stress can become internalized in their body and have implications for their health.

Would you be able to discuss the interaction between allostatic load and specific environmental factors in poor neighborhoods?

For this particular index that we use, the opportunity index, when we talk about environmental factors, we are talking about things like air quality, walkability of the neighborhood, and access to green space. What we found was that when we looked at neighborhood environment as a domain within the multiple domains of opportunity, there was an interaction between biological correlates of stress, allostatic load, and also environment indicating that, for example, people who lived in neighborhoods with poor walkability, poor air quality, or minimal green space, are more likely to have a higher allostatic load, or essentially have higher levels of stress.

The results highlight disparities and all-cause mortality based on neighborhood opportunity. Can you discuss some of these disparities and how significant they are?

What we found was that the individuals who live in neighborhoods with low opportunity, once again, operationalizing the opportunity as neighborhoods that are resource-poor, are more likely to have a worse all-cause mortality, which is death from any cause, compared [with] patients who live in neighborhoods with a high opportunity. These findings are interesting in that we also looked at an opportunity or neighborhood contextual factors within the context of allostatic load. However, there have been other studies looking at other incidences, for example, in an area of deprivation or socioeconomic status, that have found similar things where individuals who live in neighborhoods that are resource poor tend to have worse outcomes than their counterparts in neighborhoods that are resource rich.

What is the key finding from this research?

I think 1 of the things that it tells us is that we have to continue to practice medicine holistically, meaning we have to have a good understanding of some of the socio environmental stressors that our patients face, and how that influences, and how they interact with the healthcare system, and also how they participate in their care and respond to our treatments. It emphasizes the idea that we have to try to understand people in terms of where they are coming from, and what we can do as health systems to mitigate some of the adverse socioenvironmental stressors that they may face.

What kind of interventions might have to happen at the individual and neighborhood levels?

At the individual level, 1 of the new things that we are doing, at least in the inpatient setting at the Centers for Medicare and Medicaid, is requiring that we collect information on social determinants of health and also on social risk. So actually asking people, do you have transportation? Do you have housing? Are you facing food insecurity? Help us know if it is a problem. That's the first thing, but it will also help us understand how we can utilize resources like social workers, patient navigators, and financial counseling to help our patients address these health-related social needs. That is something we can do at an individual level. At a higher level, policy, it is probably looking at what well placed governmental policies can have significant implications for people's lives.

What key messages do you have for policymakers, healthcare providers, or advocacy groups regarding these disparities?

I think it is important to be inclusive when policy is being created and making sure that [we] have individuals within communities that [we] are going to make policies for at the table, but also to have a myriad of experts who bring different perspectives in terms of how we can come up with thoughtful and meaningful solutions to some of the issues that individuals who live in neighborhoods with low opportunities face.

For community oncologists, what is the most important thing to take away from this research?

It is what I alluded to before taking a holistic approach to treating patients, which is trying to understand in addition to the treatment that [we are] offering them, what health-related social needs they have. Healthcare social needs are things that people identify that are important for them to be able to participate in their healthcare. An example is transportation. Understanding the kinds of needs that patients have and then being able to help mitigate some of the stress caused by those needs can be impactful, improving patient outcomes.

What are the next steps in this research area?

We currently have 3 ongoing studies. The first study we have is a study focused on patients who have triple-negative breast cancer where we have a stress reduction intervention to see if it improves outcomes in that population. We also have a study funded by the American Society of Clinical Oncology that tries to understand the relationship between genetic ancestry, chemotherapy, and radiation therapy, and also allostatic load, which as I mentioned, is a stress. Then, the American Cancer Society also has funded us to do a study looking at allostatic load and also breast cancer molecular subtypes. We have been lucky to have a lot of opportunities to try to expand upon this work and other parts of breast cancer.

REFERENCE:

Chen JC, Elsaid MI, Handley D, et al. Association between neighborhood opportunity, allostatic load, and all-cause mortality in patients with breast cancer. J Clin Oncol. Published online February 16, 2024. doi:10.1200/JCO.23.00907