Trends of stroke hospitalisation and fatality rates in young vs. elderly people in Poland during 2010-2019 decade.

ABSTRACT

INTRODUCTION: Since the turn of the century, epidemiological studies have shown an increase in stroke hospitalisation rates among young adults in contrast to a decline in rates seen among the older population. The aim of the present study was to investigate the trends of stroke hospitalisation rates and case fatality ratios (CFR) over the decade starting in 2010 in different age groups of the Polish population. MATERIAL AND METHODS: The patients were identified on the basis of the Polish National Health Fund that gathers all the data of the Hospital Discharge Registry as well as the National Cause of Death Registry of patients with stroke who were hospitalised between 2010 and 2019 and who were diagnosed according to the International Classification of Diseases - Tenth Revision (ICD-10) with haemorrhagic stroke (HS; codes I61* and I62*) and ischaemic stroke (IS; codes I63*). RESULTS: From a total nationwide cohort of 799,132 stroke patients (86.2% with IS and 13.8% with HS) treated between 2010 and 2019, a group of 22,329 patients (2.79%) aged 18-44 years was selected, among whom 69.6% had IS and 30.4% had HS. We documented a statistically significant increase in the IS hospitalisation rate in young adults alongside a decrease of this rate in those aged > 64. Among young adults with IS, the highest increase (p = 0.001) was observed for those aged 35-44 in 2019 (up to 39.2), and was significant each year starting from 2017 (2017-2019 p < 0.01). In the case of HS, the annual number of patients did not change significantly. In 2019 (compared to 2010), a decrease in 30-day, 90-day and 1-year CFR was noted in all age groups of patients with IS and HS. Stroke aetiology of IS was diagnosed in 60% of patients. More than 40% of patients with IS were discharged with the diagnosis of stroke of unspecified cause. CONCLUSIONS: In the case of IS, opposite trends of hospitalisation rates in younger and older age groups were documented, with the highest increase of IS in patients aged 35-44. A decline in CFR was observed for both IS and HS in all age groups.