Contribution of Established Stroke Risk Factors to the Burden of Stroke in Young Adults.

BACKGROUND AND PURPOSE: As stroke in young adults is assumed to have different etiologies and risk factors than in older populations, the aim of this study was to examine the contribution of established potentially modifiable cardiovascular risk factors to the burden of stroke in young adults. METHODS: A German nationwide case-control study based on patients enrolled in the SIFAP1 study (Stroke In Young Fabry Patients) 2007 to 2010 and controls from the population-based GEDA study (German Health Update) 2009 to 2010 was performed. Cases were 2125 consecutive patients aged 18 to 55 years with acute first-ever stroke from 26 clinical stroke centers; controls (age- and sex-matched, n=8500, without previous stroke) were from a nationwide community sample. Adjusted population-attributable risks of 8 risk factors (hypertension, hyperlipidemia, diabetes mellitus, coronary heart disease, smoking, heavy episodic alcohol consumption, low physical activity, and obesity) and their combinations for all stroke, ischemic stroke, and primary intracerebral hemorrhage were calculated. RESULTS: Low physical activity and hypertension were the most important risk factors, accounting for 59.7% (95% confidence interval, 56.3-63.2) and 27.1% (95% confidence interval, 23.6-30.6) of all strokes, respectively. All 8 risk factors combined explained 78.9% (95% confidence interval, 76.3-81.4) of all strokes. Population-attributable risks of all risk factors were similar for all ischemic stroke subtypes. Population-attributable risks of most risk factors were higher in older age groups and in men. CONCLUSIONS: Modifiable risk factors previously established in older populations also account for a large part of stroke in younger adults, with 4 risk factors explaining almost 80% of stroke risk. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00414583.