1587P Joint effect of cardiovascular disease and cancer: Analysis of national health insurance data of cancer patients who had cardiovascular disease before cancer diagnosis

Abstract

Cancer patients are at higher risk of cardiovascular disease (CVD), which remains a leading cause of death in cancer survivors. With many shared modifiable risk factors, cancer and CVD often co-exist in the same individuals. As we know, previous studies did not consider their joint effect on the burden of CVD. Therefore, we evaluated the burden of CVD among cancer patients with and without co-existing CVD. We conducted a retrospective cohort study using a population-based nationwide cohort in South Korea. We included all patients aged 35 to 75 years with newly diagnosed cancer between January 1, 2006 and December 31, 2015 (N = 20,016) and a 1:3 age, sex and region matched non-cancer controls (N = 52,282). In this study, we considered CVD as ischemic heart diseases, peripheral artery disease, cerebrovascular accident and heart failure. We estimated the risk of CVD related emergency room (ER) visits, and hospitalization in non-cancer controls without co-existing CVD, and compared this risk to non-cancer controls with co-existing CVD, and cancer patients with and without co-existing CVD. During 266,034 person-years of follow-up, 8,579 participants visited ER and 10,680 experienced hospitalization related CVDs. Compared to non-cancer control without co-existing CVD, the adjusted hazard ratio (HR) in non-cancer control with co-existing CVD, and cancer patients without co-existing CVD were 1.57 (95% confidence interval, 1.39-1.76), and 1.25 (1.07-1.45) for ER visit and 1.34 (1.26-1.42), and 1.61(1.50-1.73) for hospitalization. Especially, the joint effect of cancer and co-existing CVD was much higher than expected from the independent effects of both factors (1.68, 95% CI =1.48-1.90 for ER visit; 2.23, 95% CI =2.10-2.38 for hospitalization). Patients with cancer and co-existing CVD had a higher risk of CVD events than patients with neither of these conditions. Given the co-existence of risk for cancer and CVD based on baseline factors, we suggest that joint screening for cancer and CVD should perhaps be pursued.