3721 - Marital Status and IDH-Wildtype Glioblastoma: A Propensity-Matched Analysis of Treatment Receipt and 90-Day Mortality
Presenter(s)
M. J. Lane, and R. R. Savjani; Department of Radiation Oncology, University of California, Los Angeles, Los Angeles, CA
Purpose/Objective(s):
Marital status has been associated with improved survival in glioblastoma (GBM), though the mechanisms remain unclear. We hypothesized that unmarried patients experience higher early mortality and reduced receipt of standard-of-care treatment (the Stupp regimen of concurrent chemoradiation), and that this effect varies by unmarried subtype and age.
Materials/Methods:
Patients with histologically confirmed IDH-wildtype GBM diagnosed between 2018-2022 were identified from the SEER-17 registry. A one-month landmark period was utilized to exclude early deaths and mitigate immortal time bias regarding treatment receipt. Marital status was classified as married, divorced/separated, single (never married), or widowed. Propensity score matching (1:1, married to unmarried) was performed based on age, sex, and surgical extent. Primary outcomes were receipt of any radiation therapy (RT), receipt of Stupp protocol (concurrent chemoradiation), and 90-day mortality. Multivariable logistic regression assessed the independent effect of marital status on 90-day mortality, adjusting for age, sex, race, surgical extent, and median household income. Subgroup analyses examined outcomes by unmarried category and age (<65 vs =65 years).
Results:
After propensity matching, 7,634 patients were included (3,817 married, 3,817 unmarried). Groups were well-balanced for age (61 vs 60 years), sex (52% vs 50% female), and surgical extent. Married patients were more likely to receive any RT (83% vs 74%, p<0.001) and Stupp protocol (78% vs 67%, p<0.001). Overall 90-day mortality was lower in married patients (14% vs 20%, p<0.001). On multivariable analysis stratified by age and adjusted for race, surgical extent, and median household income, widowed status was the strongest independent predictor of 90-day mortality (OR 2.67, 95% CI 1.64-4.22, p<0.001 in patients <65 years; OR 1.69, 95% CI 1.38-2.07, p<0.001 in patients =65 years). Divorced/separated and single patients also had increased mortality risk compared to married patients in both age groups (all p=0.005). Gross total resection was protective (OR 0.56, 95% CI 0.41-0.79 in <65; OR 0.39, 95% CI 0.31-0.50 in =65), while no surgical resection was associated with increased mortality (OR 1.94, 95% CI 1.36-2.78 in <65; OR 1.75, 95% CI 1.39-2.22 in =65).
Conclusion:
Unmarried patients with IDH-wildtype GBM are less likely to receive standard-of-care treatment and have significantly higher 90-day mortality. Widowed patients appear to be at particularly high risk, especially among those under 65, suggesting that partner loss, not merely absence of marriage, may be a key driver. Targeted interventions such as patient navigation and early palliative care integration may help reduce disparities in this vulnerable population.