Trends in baseline patient characteristics during the years 1995-2008: observations from Riks-Stroke, the Swedish Stroke Register.

BACKGROUND: Reported improvements in outcome in stroke patients treated in hospital are often attributed to advances in stroke care. However, secular trends in patient characteristics that are present already on admission to hospital may also contribute to improved outcome.
METHODS: Time trends for baseline data (289,854 stroke admittances) in Riks-Stroke, the Swedish national quality register for stroke care, were analyzed for the years 1995 through 2008. The following data were included: number of strokes for each year, age, sex, risk factors, stroke subtype, stroke severity, functional status and need of external home service before the stroke.
RESULTS: The number of annually reported strokes increased until 2005. The proportion of recurrent strokes decreased from 28.0 to 25.9%. The mean age at first-ever stroke increased in women, but not in men. The proportion of smokers dropped, and the proportion of patients who had treated hypertension increased. The stroke severity decreased in men. The prestroke functional status (walking, dressing, toileting) improved in both sexes over these years. More patients lived alone in 2008 than in 1995, and more had home help service.
CONCLUSIONS: Many baseline parameters in Riks-Stroke have changed over the years. This has consequences for the interpretation of outcome data. Some changes may be due to inclusion bias, others due to alterations in general health, evolution of vascular risk factors or demographics. Copyright (c) 2010 S. Karger AG, Basel.