Abstract 2654: Central Nervous System Infections And Risk of Stroke - A Population-Based Analysis

Abstract

Introduction: Central nervous system (CNS) infections include meningitis, encephalitis, and myelitis caused by various pathogens. Although CNS infections are treatable, its inflammatory process causes irreversible brain damage and neurological sequeale such as seizures, cognitive dysfunction, and focal neurological deficits in nearly 20% of the patients. Cerebrovascular complication is believed to be a common mechanism of neurological sequelae in CNS infections, but the risk has rarely been reported. Earlier researches have shown an acute respiratory or urinary tract infection episode transiently increases vascular events including stroke and acute myocardial infarction (AMI). Current studies were usually with inadequate sample sizes to find the risk of vascular complications relevant to CNS infections. Consequently, the association between CNS infections and stroke, as well as AMI, is still unclear. Hypotheses: Central nervous system (CNS) infections may increase the risk of vascular diseases including stroke and acute myocardial infarction (AMI). Methods: To investigate the risks, we conducted a retrospective cohort study by the Taiwan National Health Insurance Research Database. The study cohort comprised all adult patients with diagnoses of CNS infections during 2000 to 2005 (n=440). The comparison group comprised randomly selected patients (5 for one subject of CNS infections, n=2,200) matched with the study group by their age and sex. Patients were tracked from their index visits for at least 1 year and mean of follow-up periods among patients with and without CNS infections were 3.8 years and 4.1 years. The Kaplan-Meier survival estimations were used to compare the differences in stroke and AMI-free survival rate of patients with and without CNS infections after adjusting censoring cases. Parametric survival models were used to examine the hazard risks of stroke and AMI of CNS infections cases and their comparison controls. Results: After adjusting the patients demographic characteristics and comorbidities, the risk of patients with CNS infections developing stroke were 5.6 times greater than their comparison group (the incidence rate of stroke for patients with and without CNS infections were 16.84 and 3.03 per 1000 person-year). More than 70% of the stroke events were occurring within one year after CNS infections. The risk of AMI was not found as we compared patients with and without CNS infections. Conclusions: The population-based cohort study suggested that adult patients with CNS infections have higher risk to develop stroke but not AMI, and the risk is marked within a year after infections.