Research showed that the mortality of upper gastrointestinal hemorrhage (UGH) complicated with acute coronary syndrome (ACS) was higher than single UGH in elderly patients. This study aimed to determine the risk factors that associated with an increased risk of ACS occurrence after UGH.

A population-based nested case-control study was conducted analyzing the hospital information system database of Shengjing Hospital of China Medical University from September 1, 2009 to December 31, 2014. We included 3217 elderly patients who experienced a UGH, among which 152 cases were identified and matched 604 selected controls. Multivariate conditional logistic regression models were used to characterize risk factors associated with ACS occurrence and death after UGH.

Diabetes (odds ratio (OR) = 1.84, 95% confidence interval (CI) 1.13–2.71, P = 0.039), smoking (OR = 1.87, 95% CI 1.19–2.73, P = 0.028), vasopressin or terlipressin use (OR = 1.51, 95% CI 1.02–2.14, P = 0.043), liver cirrhosis (OR = 2.43, 95% CI 1.45–4.38, P = 0.013), hemoglobin level (OR = 2.36, 95% CI 1.65–3.79, P = 0.014) and history of ACS (OR = 1.98, 95% CI 1.13–3.49, P = 0.017) increased risk of ACS incidence in elderly patients with UGH. Moreover, diabetes (OR = 2.14, 95% CI 1.15–4.21, P = 0.041), smoking (OR = 2.93, 95% CI 1.17–5.31, P = 0.043) and hemoglobin levels (OR = 1.95, 95% CI 1.24–3.16, P = 0.038) were independent variables for the mortality underwent UGH with ACS in elderly patients.

History of diabetes, vasopressin or terlipressin use, smoking, liver cirrhosis, hemoglobin level and history of ACS are risk factors to develop ACS in elderly patients with UGH. Importantly, diabetes, smoking and lower hemoglobin level are key variables for mortality.