Hypertension in patients receiving chemotherapy is a heavily documented and significant adverse event among cancer patients. In certain cases, radiotherapy may also be associated with sustained changes in blood pressure as an adverse outcome. Recent studies have shown that following head and neck radiotherapy there is sustained and significant blood pressure reduction without orthostatic changes. Additional evidence highlights hypertension due to radiation-induced renal artery stenosis. However, association of potential long-term effects of radiation to the aorta and concomitant changes in blood pressure have not been well documented. In this retrospective study, we evaluated changes in blood pressure among patients that likely received radiation dose to the aorta.We performed a retrospective cohort study of US national health records available within the Veterans Health Administration's (VA) Corporate Data Warehouse (CDW). All work was performed under local IRB approval (IRB #4234). The inclusion criteria for this study were Veterans with prostate, esophageal, pancreatic, and gastric cancers according to ICD-9 or ICD-10-CM codes. We divided the overall cohort (n = 70143) into the following groups: 1) esophageal, pancreas, and gastric cancer patients who received radiotherapy (irradiated aorta), 2) prostate cancer patients receiving brachytherapy (other radiation), and 3) esophageal, pancreas, prostate, and gastric cancer patients who did not receive radiotherapy (unirradiated). Pre and post-treatment vital signs (systolic blood pressure [SBP], diastolic blood pressure [DBP], and pulse pressure [PP]) were evaluated for all available time points. Course start date of radiation represented day 0 in the irradiated aorta and other radiation cohorts, while the average number of days from the first occurrence of initial diagnosis to course start date for respective cancers was considered day 0 in the unirradiated aorta cohort. Interrupted time series analyses were conducted using custom R scripts, with pairwise statistical comparisons by t-test.Within the cohort we observed no significant differences in pre vs. post-treatment changes in SBP, DBP, or PP for patients that did not receive radiation to the aorta across all disease sites. Similarly, there was no change in these metrics among patients with prostate cancer, whether or not they received brachytherapy. Interestingly, we observed no difference in pre- vs. post-treatment changes in SBP, DBP, or PP in patients with esophageal, pancreas, or gastric malignancies receiving radiation to the aorta - with the understanding that this is an unselected cohort regarding actual site of radiation, as we did not exclude patients receiving radiation to distant metastatic sites CONCLUSION: Our preliminary analysis demonstrates no evidence to suggest that presumptive radiation dose to the aorta results in significant changes to SBP, DBP, or PP in a mixed cohort of cancer patients.