Study links socioeconomic disadvantage with increased post-cystectomy mortality

A study published in Urology found higher rates of mortality and worse oncologic outcomes in bladder cancer patients residing in more socioeconomically disadvantaged neighborhoods who underwent radical cystectomy.¹

The study utilized the area deprivation index (ADI) to assess the patients’ socioeconomic status and found that patients in the most disadvantaged quartile were more likely to die within 90 days of surgery and had worse oncologic outcomes including overall survival and recurrence-free survival.

Byron H. Lee, MD, PhD

“This study really shows the power of ADI in predicting postoperative and oncologic outcomes for bladder cancer patients undergoing radical cystectomy. ADI also allows us to systematically identify patients most at risk for adverse outcomes so that we can better serve them,” says Byron H. Lee, MD, PhD, Cleveland Clinic urologist and senior author of the study. Lee led the study along with Jacob Knorr, a medical student in the Cleveland Clinic Lerner College of Medicine and incoming urology resident.

ADI was first developed in 2002 to examine the link between census tract-based socioeconomic measures and mortality, and it has also been used to examine medical and surgical disparities.

Radical cystectomy in context

In patients who are fit for surgery, radical cystectomy with or without chemotherapy remains the gold standard for the management of muscle invasive bladder cancer. However, radical cystectomy is a long and complex procedure that is often performed in older patients with many coexisting illnesses. Thus, this procedure is associated with high complication rates.

Bladder cancer experts at Cleveland Clinic have continuously refined their surgical technique and introduced care pathways to significantly reduce complication and readmission rates after radical cystectomy. Nonetheless, approximately 2%-3% of patients still die within 90 days of surgery.

Identifying determinants of mortality

The goal of the current study was to assess the factors associated with a higher risk of mortality after surgery.

“We wanted to figure out what are the determinants of mortality within the 90 days of surgery,” he says. “The hypothesis that we’re testing here is that not only is it dependent on the patients’ underlying health status, but also their socioeconomic position.”

Comparing radical cystectomy outcomes with socioeconomic position

The retrospective single-institution study analyzed the outcomes of 906 patients who underwent radical cystectomy for bladder cancer between 2011 and 2019. Investigators assessed the rates of major complications within 30 and 90 days of surgery, mortality, and overall and recurrence-free survival. ADI was used to assess the patients’ socioeconomic position.

“ADI is a composite measure that ranks neighborhoods by socioeconomic disadvantage using census block data. Some of the variables that are used to calculate a neighborhood’s ADI include measures of education, income, employment, household characteristics, and housing such as home values and percent housing units that are occupied,” Lee explained. “Interestingly, neighborhoods in the same zip code that are adjacent to each other may have vastly different ADI percentile ranks.”

In this study, Lee’s team divided the patient population into four ADI quartiles. Twenty percent of the patients were in the most disadvantaged quartile and 13% of patients were in the least disadvantaged quartile. The middle quartiles contained about two-thirds of the patients. The patients in the most disadvantaged quartile were more likely to be younger, African American, and active smokers.

“We also looked at other variables known to be associated with surgical outcomes such as medical comorbidities and nutrition levels, but did not find any differences among the four ADI quartiles,” said Lee. “Also, there were no significant differences in the care that the patients received. We found similar rates of neoadjuvant chemotherapy use and continent diversion choice. There were also no differences in the rates of open versus robotic surgery.”

Closer follow-up is needed in patients at high risk of poor outcomes

The study found that the patients belonging to the most disadvantaged ADI quartile were at highest risk for a poor outcome after radical cystectomy.

“Although none of the least disadvantaged patients died within 90 days of surgery, 6.5% of the most disadvantaged patients died within 90 days. This was three times the overall 90-day mortality rate of the entire population,” Lee said. “Half of all 90 day deaths occurred in patients from the most disadvantaged ADI.”

He notes that this finding was surprising and speculates that there are many factors contributing to higher 90-day mortality rates in patients from the most disadvantaged ADI quartile. His team examined each case individually and noted a trend toward longer time to first readmission in the most disadvantaged patients. They plan to investigate why there is a delay in obtaining care for these patients.

“The other important finding in this study is that the most disadvantaged patients also had worse cancer outcomes — overall survival and recurrence-free survival, mainly because their disease was more advanced and more aggressive at the time they presented to us,” he said.

“Moving forward, I think that one of the things that we need to do is formulate a strategy to incorporate and use ADI in perioperative care for patients undergoing radical cystectomy. For example, we may follow the most disadvantaged patients even more closely after surgery via phone calls or some other means. Outreach and education of the community physicians serving the socioeconomically disadvantaged areas would also be an important way to reduced mortality rates in this patient population,” Lee concluded.

Reference

1. Knorr JM, Campbell RA, Cockrum J, et al. Neighborhood socioeconomic disadvantage associated with increased 90-day mortality following radical cystectomy [published online ahead of print December 29, 2021]. Urology. doi: 10.1016/j.urology.2021.10.048