Abstract 17170: Association of Plasma Homocysteine Levels in Cancer Survivors - Data From Framingham Heart Study Offspring Cohort

Abstract

Introduction: Cancer survivors experience a high prevalence of vascular remodeling from their anti-cancer therapies, which can lead to arterial stiffness. High plasma homocysteine (Hcy) is associated with increased cardiovascular disease risk via its role in decreasing nitric oxide bioavailability and impairing vascular function. However, there is limited work on its role in cancer survivorship. We, therefore, hypothesized that survivors of breast, gastrointestinal, and prostate cancer with elevated plasma Hcy values have higher arterial stiffness and lower endothelial function compared to those with low plasma Hcy. Methods: We evaluated cardiovascular disease-free cancer survivors in the Framingham Heart Study Offspring Cohort (n=196, 66±8 years old, 55.1% women, 26.4±1.2 years from cancer diagnosis, Range: [23.8 - 29.6 years]) with plasma Hcy measurements. The cohort median plasma Hcy was used to define low (<8.16 μmol/L) and high Hcy (≥8.16 μmol/L) groups. Arterial stiffness was assessed via carotid-femoral pulse wave velocity (cfPWV). Peripheral vascular endothelial function was assessed via endothelium-dependent brachial artery flow-mediated dilation (FMD). Differences in cfPWV, FMD, and cardiovascular risk factors were assessed via independent sample t-test or chi-square test. Differences in cfPWV and FMD were further assessed via one-way ANCOVA with age, sex, and cardiovascular medications included as covariates. Results: cfPWV was significantly higher in the high Hcy (9.9±1.5m/s) vs. low Hcy group (8.5±1.9m/s, p=0.005); however, there were no differences in FMD between groups (2.4±1.7 vs. 2.7±2.0%, p=0.42). After controlling for our covariates, cfPWV was still significantly higher in the high Hcy group (Mean[95% CI]): (9.8[9.0-10.61]) compared to the low Hcy group (8.5[8-9.1]) (p=0.015). Conclusions: Our findings suggest an association between elevated Hcy and an increase in arterial stiffness in cancer survivors. This supports the potential adverse consequences of vascular stiffening following cancer diagnosis and treatment which could have long-term cardiovascular health implications.