The role that social determinants of health play in outcomes for patients with MIBC

In this interview, David Miller, MD, highlights findings from the study, “Insurance type and area deprivation are associated with worse overall mortality for patients with muscle-invasive bladder cancer,”¹ for which he served as the lead author. Miller is a urology resident at the University of Pittsburgh Medical Center in Pennsylvania.

David Miller, MD

Could you describe the background for this study?

As we know, social determinants of health have been linked to higher risks for all kinds of medical conditions from cardiovascular diseases to endocrine, nutritional, and metabolic diseases; respiratory disorders; digestive diseases; and all-cause mortality. Within our field overall, there is a growing recognition of the importance of social determinants of health on cancer outcomes, but limited evidence specific to muscle-invasive bladder cancer. Lower socioeconomic status, female sex, non-private health insurance, and being a racial minority are associated with increased bladder cancer-specific mortality as previous work has shown.

A potential reason for these differences in mortality stems from the fact that social determinants can negatively affect outcomes on many levels, ranging from the individual to the societal level. They are also affected by multiple domains, including the biological, behavioral, physical, and socio-cultural environment, as well as health care system. This is nicely summarized in the National Institute on Minority Health and Health Disparities Framework. I encourage people to look at that.

However, only a few prior studies have specifically examined the specific effect of social determinants of health on outcomes for patients with muscle-invasive disease. Further, as treatment for muscle-invasive bladder cancer becomes more concentrated in centers of excellence, traditionally underserved patient groups may be less likely to receive care at these centers.

We sought to better understand the role of social determinants and type of treatment received on outcomes for patients with muscle-invasive bladder cancer. To do this, we examined the association of select proxies for social determinants with overall and cancer-specific mortality for patients with muscle-invasive bladder cancer. We used a large state registry, the Pennsylvania Cancer Registry, which collects demographic, insurance, and clinical information on every patient with cancer within the state. We identified all patients diagnosed with nonmetastatic muscle-invasive bladder cancer between 2010 and 2016 based on clinical and pathologic staging. We then used the Area Deprivation Index, or ADI, as a surrogate for socioeconomic status and Rural Urban Commuting Area, or RUCA codes to classify urban large town or rural communities. ADI was reported in quartiles, with 4 representing the lowest socioeconomic status.

What were your notable findings? Were any of those surprising to you and your coauthors?

We found an association between select indicators of key social determinants of health and mortality. These proxies for social determinants of health that we found to be associated with higher overall mortality included living in a more deprived area, as well as having Medicaid or Medicare insurance. However, higher area deprivation and Medicaid or Medicare insurance were not actually associated with increased bladder cancer-specific mortality. And then lastly, female patients and those receiving non-standard treatment have worse overall mortality and bladder cancer-specific mortality.

It's somewhat surprising that an association between ADI and bladder cancer-specific mortality was not found in our analysis. Possible explanations include that these patients could be actually receiving care at [National Cancer Institute] NCI designated cancer centers, or that these patients are masked by the fact that they presented a higher stage of disease due to known issues with screening in these populations.

What needs to be done in order to overcome some of those differences in outcomes?

We show, and others have shown, that socioeconomic factors contribute to cancer outcomes. These factors are potentially modifiable and include employment levels, education, health behaviors, protection for taking time off work, access to care, and availability of insurance. Tackling these issues will require high-level policy decisions, which is challenging given the nature of polarizing politics these days.

Is any further research on this topic planned? If so, what might that focus on?

Future research is ongoing. Currently, our group is exploring pharmacoequity in urologic oncology, as well as several projects looking at variation in cancer screening. Patients living in the areas with the highest poverty level tend to present with more advanced disease than those living in more affluent areas, potentially due to difficulties with accessing care for screening purposes. It's possible that this advanced disease is then a major contributor to an increased risk of bladder cancer death.

What is the take-home message for urologists?

We as practicing urologists need a better understanding of the effects of social determinants on our patients' outcomes. This is important both at the advocacy level for the development of health policies and initiatives to decrease disparities in bladder cancer care, as well as the individual level to attempt to be more cognizant of the issues that our patients are facing and perhaps be more accommodating towards ensuring that they are receiving the care that they need.

Reference

1. Miller DT, Sun Z, Grajales V, et al. Insurance type and area deprivation are associated with worse overall mortality for patients with muscle-invasive bladder cancer. Urology. [published online ahead of print April 5, 2023.] Accessed May 3, 2023. doi:10.1016/j.urology.2023.02.045.