To Örebro University

Background: Stroke incidence is decreasing in most developing countries. However, worrisome trends of an increase in the younger population have been described.

Aim: To investigate sex differences and longitudinal changes in ischemic stroke regarding incidence, cardiovascular risk factors, and outcome, in the young.

Methods: This is an observational study based on the data from the Swedish national stroke registry, Riksstroke. Patients, 18-54 years of age, having ischemic stroke between 2005 and 2018 were included, resulting in a study population of 16,210 patients.

Results: The incidence was higher in men than in women (30.6 vs. 19.1 per 100,000, P < 0.001). After an initial increase, the incidence stabilized and then decreased, resulting in a similar level in 2018 as in 2005. Atrial fibrillation, diabetes, and usage of anti-hypertensives at stroke onset were more common among men and did not change over time. Smoking was common and slightly more so in women, but with a reduced prevalence in both men and women during the study period. Dependency in Activities of Daily Living (ADL) and case fatality showed no clear trends or sex differences.

Conclusions: The results show that there are sex differences in ischemic stroke in the younger age group regarding incidence and vascular risk factors, particularly smoking. Temporal trends in stroke incidence are difficult to interpret as fluctuations are substantial, largely due to stroke being quite uncommon in the younger population.