Improvement of survival in Polish stroke patients is related to reduced stroke severity and better control of risk factors: the Krakow Stroke Database

Arch Med Sci. 2016 Jun 1;12(3):552-5. doi: 10.5114/aoms.2016.59928. Epub 2016 May 18.

Abstract

Introduction: In the last decade, the stroke mortality rate in Poland significantly decreased. We hypothesised that stroke severity, the major determinant of outcome, is lowered in Polish stroke patients.

Material and methods: We compared the stroke severity in two cohorts of first-ever ischaemic stroke patients admitted within 24 h after stroke onset to the Department of Neurology, Jagiellonian University, Krakow in the years 1994-2000 and 2008-2012. To assess stroke severity we used the National Institute of Health Stroke Scale (NIHSS). We defined mild stroke as an NIHSS score ≤ 4.

Results: We included 816 patients hospitalised in the years 1994-2000 and 569 patients hospitalised in the years 2008-2012. NIHSS score on admission was higher in the former (mean: 12.0 ±7.0 vs. 8.0 ±6.0, p < 0.01), and the frequency of mild stroke was higher in the latter (12.7% vs. 41.8%, p < 0.01). Although the frequency of hypertension (67.3% vs. 81.2%, p < 0.01), diabetes mellitus (20.8% vs. 26.4%, p = 0.02) and atrial fibrillation (20.7% vs. 26.2%, p = 0.02) was higher in patients hospitalised in the years 2008-2012, the systolic and diastolic blood pressure values and the frequency of fasting hyperglycaemia were lower in this cohort. This cohort also less frequently suffered from hypercholesterolaemia (25.4% vs. 16.3%, p < 0.01).

Conclusions: Reduced stroke severity is associated with better recognition and control of risk factors and explains the improvement of survival in Polish stroke patients.

Keywords: hypercholesterolaemia; hypertension; ischaemic stroke; risk factors; stroke severity.