History of ischemic stroke associated with worse clinical outcomes in patients with pulmonary embolism.

Abstract

Pulmonary embolism (PE), which comprises approximately one-third of all venous thromboembolism (VTE),1 exhibits various clinical presentations, ranging from incidentally discovered emboli to hemodynamic instability and death, and its 1-year mortality rate has been reported to exceed 20%.2 Ischemic stroke is one of the major cardiovascular disorders associated with thrombosis as a common pathology along with ischemic heart disease and VTE.3 According to recent studies, the occurrence of PE in patients with ischemic stroke is associated with poor clinical outcomes.4,5 However, information on how the history of ischemic stroke affects patients with PE in terms of clinical manifestations and survival is limited. Thus, the objective of this retrospective study was to investigate whether clinical characteristics and outcomes might differ according to the history of ischemic stroke in patients with PE. Data were collected from patients with PE who were hospitalized between January 2003 and May 2019 at Kyungpook National University Hospital (KNUH), a tertiary referral center in Daegu, South Korea. This study was approved by the Institutional Review Board of the KNUH, which waived the requirement for written informed consent due to its retrospective nature. Patients with PE diagnosed using multidetector-row computed tomography (CT) were included and divided into a stroke group (with a history of ischemic stroke) and a control group (without a prior ischemic stroke). The history of ischemic stroke before the diagnosis of PE was identified by comprehensively reviewing clinical diagnosis and past hospitalization from the medical records, regardless of the time of diagnosis. Clinical characteristics, blood biomarkers, and CT findings were compared between the two groups. To identify predictors of PE-related in-hospital mortality, multivariable logistic regression analysis was performed using Firth’s Penalized Likelihood method. Results of comparisons of clinical characteristics, blood biomarkers, and CT findings are summarized in Table 1. Of 1339 patients with PE, 115 (8.6%) had a history of ischemic stroke. The median follow-up time was 306 days (IQR, 73–1082 days). The proportion of unprovoked PE was lower in the stroke group than in the control group (p = 0.003), whereas the frequency of immobilization was higher (p < 0.001). Comorbidities, including diabetes mellitus (p = 0.035), ischemic heart disease (p = 0.002), and atrial fibrillation (p < 0.001), were more common in the stroke group. Despite the insignificant difference between the two groups in PE severity index (PESI) and CT findings, PE-related in-hospital mortality was significantly higher in the stroke group than in the control group (p = 0.002). The patients were further reclassified into those with (n = 22) and without (n = 1317) PE-related in-hospital death (online supplementary material: Table S1). Variables with p < 0.05 in univariate analysis were included in the multivariable logistic regression analysis. Atrial fibrillation (odds ratio [OR], 3.64; 95% CI, 1.18‒11.29; p = 0.022), PESI class IV‒V (OR, 3.98; 95% CI, 1.72‒9.25; p = 0.001), right ventricular dilation on CT (OR, 3.52; 95% CI, 1.41‒8.78; p = 0.007), and stroke (OR, 4.87; 95% CI, 1.92–12.35; p < 0.001) were identified as an independent factor for predicting PE-related in-hospital mortality. Few studies have reported the proportion of patients with a history of stroke in patients with PE. Based on data of 2488 patients hospitalized with VTE, Piazza et al. reported that 288 (11.6%) had a clinical history of stroke and that prior stroke was associated with an increased risk of short-term mortality compared with patients without stroke.6 Given that VTE encompasses deep vein thrombosis (DVT) and PE, which are in the same disease spectrum,7 our data are consistent with History of ischemic stroke associated with worse clinical outcomes in patients with pulmonary embolism