The influence of social determinants of health on vaccination uptake in cancer survivors in the United States.

523 Background: Despite improved longevity, infection remains one of the leading causes of non-cancer-related deaths among cancer survivors. Vaccination is a critical preventive measure to reduce infection-related morbidity and mortality, yet uptake remains suboptimal, particularly in populations facing social and economic challenges. Social determinants of health (SDoH) are non-medical factors that influence health outcomes. Our study seeks to examine the association of SDoH on vaccination uptake in cancer survivors. Methods: Cancer survivors (n = 52,987) with known vaccination status for influenza, COVID-19, pneumococcal, or zoster and SDoH information were included from the 2022 and 2023 Behavioral Risk Factor Surveillance System (BRFSS). SDoH score was generated by item response theory modeling to account for the underlying relevance using the following factors: unsatisfied with life, lack of social/emotional support, feeling lonely, mental distress, unemployment, receiving SNAP, food insecurity, housing insecurity, utility insecurity, transportation insecurity, and cost as a barrier to health care. Higher SDoH scores indicated greater social disadvantage. A multivariable logistic regression model was created to determine the association between SDoH score and vaccination uptake, after adjusting for potential confounders. Results: 62.0% of cancer survivors received the influenza vaccine, 88.2% received at least 2 doses of the COVID vaccine, 59.6% received the pneumococcal vaccine, and 54.5% received zoster vaccination. 55.3% of cancer survivors reported having at least one SDoH factor. The most common SDoH factors were feeling mentally distressed (33.5%), lack of social/emotional support (28.6%), and food insecurity (11.6%). Cancer survivors had higher SDoH scores compared to the national average with a mean SDoH score of -0.09. Higher SDoH scores were associated with lower likelihood of pneumococcal vaccination (odds ratio [OR]:0.9, 95% confidence interval [CI]: 0.84, 0.97) and zoster vaccination (OR 0.84, 95%CI: 0.76, 0.93). Similar trends were observed between SDoH scores and influenza (OR 0.93, 95%CI: 0.87, 1) and COVID-19 vaccination (OR 0.89, 95%CI: 0.76, 1.04) but not statistically significant. Conclusions: Cancer survivors who faced more social disadvantages were less likely to receive vaccinations. Targeted public health interventions are needed to address these SDoH-related barriers and ensure equitable access to vaccination for this vulnerable population.