Citations

e16157 Background: Liver cancer mortality remains a major public health burden in the United States despite advances in prevention and treatment. Psychoactive substance use disorder (PSUD) is an increasingly prevalent comorbidity; however, national trends and disparities in liver cancer mortality among adults with PSUD remain poorly characterized. Methods: We conducted a retrospective analysis of liver cancer-related deaths among U.S. adults aged 25 years and older with PSUD from 1999 to 2023 using Centers of Disease Control (CDC) Wide Ranging Online Data for Epidemiological Research (WONDER) mortality database. Age-adjusted mortality rates (AAMRs) were calculated per 100,000 population and stratified by census region, state, urban–rural status, sex, and race/ethnicity. Temporal trends were assessed using Joinpoint regression to estimate average annual percent change (AAPC). Statistical significance was determined using p-value (<0.05). Results: Overall liver cancer related AAMR per 100,000 among adults with PSUD significantly increased from 0.15 in 1999 to 1.02 in 2023 (AAPC: 7.47; 95% CI: 6.33 to 8.61; p < 0.000001). The overall mortality burden was higher in males. However, females experienced larger rises in mortality (AAPC: 10.03; 95% CI: 8.85 to 11.24; p < 0.000001) as compared to males (AAPC: 7.30; 95% CI: 5.78 to 8.84; p < 0.000001). Marked racial disparities were observed, with non-Hispanic Black and non-Hispanic White individuals experiencing the highest mortality rates with persistent increases over time, while Hispanic/Latino populations exhibited modest and variable trends. A substantial geographic variability was observed, with the greatest increases in the Midwest and the South. State-level analysis revealed higher mortality rate in Oregon (1.27) followed by Washington (1.12) and Texas (1.06) respectively. Both rural and urban areas experienced a sharp rise in mortality with AAPC being slightly higher in rural areas (AAPC: 10.34) as compared to urban areas (AAPC: 9.67). Conclusions: Liver cancer mortality among U.S. adults with PSUD has risen markedly over the past two decades, with substantial demographic and geographic disparities. These findings highlight the need for integrated liver cancer screening and substance use disorder interventions targeting high-risk populations. Variables AAMR (95% CI) in 2023 AAPC (95% CI) Overall 1.02 (0.98 –1.05) 1999-2023: 7.47* (6.33 – 8.61) Female 0.42 (0.39 – 0.46) 1999-2023: 10.03* (8.85 – 11.24) Men 1.69 (1.62 –1.76) 1999-2023: 7.30* (5.78 – 8.84) White 1.05 (1.0 –1.09) 1999-2023: 9.52* (8.08 – 10.98) Black / African Americans 1.22 (1.09 – 1.35) 1999-2023: 6.59* (5.50 – 7.68) Hispanics / Latinos 0.75 (0.65 – 0.84) 1999-2023: 1.26 (-1.01 – 3.60) AAMR (95% CI) in 2020 AAPC (95% CI) Rural 1.51 (1.39 – 1.62) 1999-2020: 10.34* (5.05 – 15.90) Urban 0.92 (0.82 – 0.95) 1999-2020: 9.67* (7.32 – 12.06)

e16023 Background: Stroke is an underrecognized cause of death among patients with gastric cancer. While overall cancer mortality has improved, less is known about long-term trends and disparities in stroke-related deaths. We examined national patterns in stroke mortality among gastric cancer patients from 1999 to 2023. Methods: U.S. national mortality data were used to calculate age-adjusted mortality rates (AAMR) per 100,000. Joinpoint regression identified temporal changes and estimated annual percent change (APC) and average annual percent change (AAPC). Analyses were stratified by age, sex, race and ethnicity, census region, and urbanization. Results: Between 1999 and 2023, an overall decline in stroke-related mortality was noted with AAMR falling from 167.29 to 111.35 per 100,000 people (AAPC −1.70%, 95% CI −1.9 to −1.5). The decline was greatest between 2002 and 2009 (−5.28% per year) after which it began to plateau until it rose significantly between 2018 and 2021 (APC 6.56%) followed by a decline after 2021 (−3.63%). Older adults had the highest level of stroke related mortality, and therefore the greatest reduction over time (from 756.36 to 479.63) with a total reduction of −36.6% yet they saw a significant increase in mortality between 2018 and 2021. Middle aged patients had little overall improvement and demonstrated the steepest recent increase (APC 8.46%). Younger patients concluded the study period at rates similar to those seen in 1999. Men demonstrated a greater incidence of stroke related mortality compared to women (118.67 vs 104.15 in 2023) with similar trends over time. Racial disparities were present with Black patients showing the highest stroke related mortality in all years (from 242.47 to 156.26) and the largest recent increase (APC 7.37%). Regionally, the South and rural areas carried the highest mortality burden; however, all geographic areas demonstrated an identical increase between 2018 and 2021. Conclusions: Although stroke-related mortality among gastric cancer patients has declined over two decades, recent nationwide increases highlight ongoing vulnerability and persistent disparities. Targeted integration of cardiovascular risk assessment and stroke prevention into gastric cancer care may help sustain progress and reduce inequities. Group (Category A / Category B) AAMR 1999 (A / B) AAMR 2023 (A / B) Recent Surge Trend 2018–2021 (APC) Overall 167.3 111.4 +6.6%* Sex (Male / Female) 181.5 / 156.2 118.7 / 104.2 +6.8%* / +6.2%* Race (NH White / NH Black) 160.4 / 242.5 108.2 / 158.4 +6.3%* / +7.4%* Race (Hispanic / Asian) 140.3 / 153.6 97.7 / 80.0 +6.9%* / +5.2%* Age (Young / Middle) 6.7 / 47.7 6.7 / 42.3 +7.8%* / +8.5%* Age (Old 65+) 756.4 479.6 +6.2%* Region (Northeast / Midwest) 141.5 / 172.0 82.7 / 115.3 +4.4%* / +6.7%* Region (South / West) 177.5 / 171.4 125.7 / 107.2 +6.9%* / +6.2%* An asterisk (*) indicates that the APC is statistically significant (p < 0.05).

With the increased availability of computational resources, the past decade has seen a rise in the use of computational fluid dynamics (CFD) for medical applications. There has been an increase in the application of CFD to attempt to predict the rupture of intracranial aneurysms, however, while many hemodynamic parameters can be obtained from these computations, to date, no consistent methodology for the prediction of the rupture has been identified. One particular challenge to CFD is that many factors contribute to its accuracy; the mesh resolution and spatial/temporal discretization can alone contribute to a variation in accuracy. This failure to identify the importance of these factors and identify a methodology for the prediction of ruptures has limited the acceptance of CFD among physicians for rupture prediction. The International CFD Rupture Challenge 2013 seeks to comment on the sensitivity of these various CFD assumptions to predict the rupture by undertaking a comparison of the rupture and blood-flow predictions from a wide range of independent participants utilizing a range of CFD approaches. Twenty-six groups from 15 countries took part in the challenge. Participants were provided with surface models of two intracranial aneurysms and asked to carry out the corresponding hemodynamics simulations, free to choose their own mesh, solver, and temporal discretization. They were requested to submit velocity and pressure predictions along the centerline and on specified planes. The first phase of the challenge, described in a separate paper, was aimed at predicting which of the two aneurysms had previously ruptured and where the rupture site was located. The second phase, described in this paper, aims to assess the variability of the solutions and the sensitivity to the modeling assumptions. Participants were free to choose boundary conditions in the first phase, whereas they were prescribed in the second phase but all other CFD modeling parameters were not prescribed. In order to compare the computational results of one representative group with experimental results, steady-flow measurements using particle image velocimetry (PIV) were carried out in a silicone model of one of the provided aneurysms. Approximately 80% of the participating groups generated similar results. Both velocity and pressure computations were in good agreement with each other for cycle-averaged and peak-systolic predictions. Most apparent “outliers” (results that stand out of the collective) were observed to have underestimated velocity levels compared to the majority of solutions, but nevertheless identified comparable flow structures. In only two cases, the results deviate by over 35% from the mean solution of all the participants. Results of steady CFD simulations of the representative group and PIV experiments were in good agreement. The study demonstrated that while a range of numerical schemes, mesh resolution, and solvers was used, similar flow predictions were observed in the majority of cases. To further validate the computational results, it is suggested that time-dependent measurements should be conducted in the future. However, it is recognized that this study does not include the biological aspects of the aneurysm, which needs to be considered to be able to more precisely identify the specific rupture risk of an intracranial aneurysm.