Risk of Coronary Heart Disease and Ischemic Stroke Incidence in Gastric Cancer Survivors: A Nationwide Study in Korea

Background: Small studies suggest improvement of cardiovascular risk profiles and reduced cardiovascular mortality after gastrectomy for gastric cancer. In our study using national health insurance data, we investigated coronary heart disease (CHD) and ischemic stroke incidence among gastric cancer patients who received gastrectomy compared with general population controls. Methods: A total of 98,936 gastric cancer patients were included in the study and matched to non-cancer controls via 1:1 propensity score matching. Competing risk regression analysis was used to determine the relative risk of CHD and ischemic stroke, with cancer mortality as the competing risk. Changes in cardiovascular risk profile before and after gastrectomy were tested, and factors associated with CHD or ischemic stroke incidence among gastric cancer patients were analyzed. Results: Compared with the matched controls, gastric cancer patients who received gastrectomy were shown to have a decreased risk for both CHD (subdistribution hazard ratio [SHR] 0.60, 95% confidence interval [CI] 0.57–0.63) and ischemic stroke (SHR 0.72, 95% CI 0.69–0.75). Decreases in body mass index (BMI), blood pressure, blood sugar, and lipid and hemoglobin levels were marked after gastrectomy. Among gastric cancer patients, those who lost > 5% of their body weight were at lower risk of developing CHD (SHR 0.82, 95% CI 0.71–0.96) and ischemic stroke (SHR 0.85, 95% CI 0.75–0.98). Conclusions: CHD and ischemic stroke risk decreased after gastrectomy. The amount of weight loss and accompanying metabolic changes seemed to mediate the reduction of such risk. Reassessment of cardiovascular risk factors after gastrectomy and consideration of cardiovascular risk in the selection of treatment modality are suggested.