Incidence and risk conditions of ischemic stroke in older adults

ObjectiveThe objective of this study was to investigate incidence and mortality from ischemic stroke in older adults with specific underlying chronic conditions, evaluating the influence of these conditions in developing stroke. Materials & methodsPopulation-based cohort study involving 27,204 individuals 60 years old in Southern Catalonia, Spain. All cases of hospitalization from ischemic stroke (confirmed by neuro-imaging) were collected from 01/12/2008 until 30/11/2011. Incidence rates and 30-day mortality were estimated according to age, sex, chronic illnesses, and underlying conditions. Multivariable Cox regression analysis was used to calculate Hazards Ratio (HR) and estimate the association between baseline conditions and risk of developing stroke. ResultsMean incidence rate reached 453 cases per 100,000 person-years. Maximum rates appeared among individuals with history of prior stroke (2926 per 100,000), atrial fibrillation (1815 per 100,000), coronary artery disease (1104 per 100,000), nursing-home residence (1014 per 100,000), and advanced age 80 years (1006 per 100,000). Thirty-day mortality was 13% overall, reaching 21% among patients over 80 years. Age [HR: 1.06; 95% confidence interval (CI): 1.04-1.07], history of prior stroke (HR: 5.08; 95% CI: 3.96-6.51), history of coronary artery disease (HR: 1.65; 95% CI: 1.21-2.25), atrial fibrillation (HR: 2.96; 95% CI: 2.30-3.81), diabetes mellitus (HR: 1.55; 95% CI: 1.23-1.95), and smoking (HR: 1.64; 95% CI: 1.15-2.34) emerged independently associated with an increased risk of ischemic stroke. ConclusionIncidence and mortality from ischemic stroke remains considerable. Apart from age and history of atherosclerosis (prior stroke or coronary artery disease), atrial fibrillation, diabetes, and smoking were the underlying conditions most strongly associated with an increased risk.