6. QUALITY AND OUTCOMES OF CARE Mortality following ischaemic

Stroke is the second leading global cause of behind based medical interventions and access to high-quality heart and accounted for over 10% of total specialised facilities such as stroke units (OECD, 2015[3]). worldwide in 2013 (American Heart Association, 2017[1]). A Timely care is particularly important, and advances in stroke occurs when the blood supply to a part of the brain is technology are leading to new models of care to deliver interrupted, leading to ( death) of the affected reperfusion therapy in an even more speedy and efficient part. Of the two types of stroke, about 85% are ischaemic manner, whether through pre-hospital triage via telephone (caused by clotting) and 15% are haemorrhagic (caused by or administering the therapy in the ambulance (Chang and bleeding). Prabhakaran, 2017[4]). Figure 6.15 shows the case-fatality rates within 30 days of hospital admission for ischaemic stroke where the death occurred in the same hospital as the initial admission Definition and comparability (unlinked data). Figure 6.16 shows the case-fatality rate where deaths are recorded regardless of where they National case-fatality rates are defined in indicator occurred, including in another hospital or outside the “Mortality following acute myocardial infarction”. hospital where the stroke was first recorded (linked data). Hospital-level stroke mortality rates use a different The indicator using linked data is more robust because it methodology from national rates. Hospital rates are captures fatalities more comprehensively than the same- adjusted for age, sex, co-morbidity, stroke severity and hospital indicator, but it requires a unique patient identifier previous stroke (linked data only). The reference and linked data, which are not available in all countries. population for hospital rates is constructed from data Across OECD countries, 7.7% of patients in 2017 died within from participating countries. The hospital-level 30 days of hospital admission for ischaemic stroke using ischaemic stroke definition also differs from the unlinked data (Figure 6.15). The case-fatality rates were national indicator, using only ICD-10 code I63 (cerebral highest in Slovenia, Poland, Lithuania and Latvia, all with infarction). mortality rates over 12%. Rates were less than 4% in Norway, Figure 6.17 is a turnip plot that graphically represents Korea, Japan and Costa Rica. Low rates in Japan are due in the relative dispersion of rates. A limitation of this type part to recent efforts dedicated to improving the treatment of representation is the inability to detect statistically of stroke patients in hospitals, through systematic blood significant variations. Countries are ordered according pressure monitoring, major material investment in to ascending level of dispersion as measured by the hospitals and establishment of stroke units (OECD, 2015[2]). interquartile range (between the 25th and 75th Across the 23 countries that reported linked data rates, percentile) of rates. Hospitals with fewer than 50 12.3% of patients died within 30 days of being admitted to ischaemic stroke admissions were excluded from both hospital for stroke (Figure 6.16). This figure is higher than figures to improve data reliability. the same-hospital indicator because it only counts each patient once and captures all deaths. Treatment for ischaemic stroke has advanced dramatically over the last decade, with systems and processes now in References place in many OECD countries to identify suspected [1] American Heart Association (2017), Heart Disease and Stroke ischaemic stroke patients as early as possible and to deliver Statistics 2017 at-a-Glance. acute reperfusion therapy quickly. Between 2007 and 2017, [4] Chang, P. and S. Prabhakaran (2017), “Recent advances in the case-fatality rates for ischaemic stroke decreased management of acute ischemic stroke”, F1000Research, substantially across OECD countries: from 10.1% to 7.7% for http://dx.doi.org/10.12688/f1000research.9191.1. unlinked data rates and from 14.6% to 12.6% for linked data [3] OECD (2015), Cardiovascular Disease and Diabetes: Policies for rates. Better Health and Quality of Care, OECD Health Policy Studies, National measures of ischaemic stroke are affected by OECD Publishing, Paris, https://dx.doi.org/ within-country variations in performance at the hospital 10.1787/9789264233010-en. level. Reducing this variation is key to providing equitable [2] OECD (2015), OECD Reviews of Health Care Quality: Japan care and reducing overall mortality rates. Figure 6.17 2015: Raising Standards, OECD Reviews of Health Care presents the dispersion of ischaemic stroke 30-day case- Quality, OECD Publishing, Paris, https://dx.doi.org/ fatality rates across hospitals within countries, using both 10.1787/9789264225817-en. unlinked and linked data. Reducing this variation requires high-quality stroke care for all, including timely transportation of patients, evidence-

130 HEALTH AT A GLANCE 2019 © OECD 2019 6. QUALITY AND OUTCOMES OF CARE

Mortality following ischaemic stroke

Figure 6.15. Thirty-day mortality after admission to hospital for ischaemic stroke based on unlinked data, 2007 and 2017 (or nearest year)

2007 2017 Age-sex standardised rate per 100 admissions of adults aged 45 years and over 30 25 20.4

20 15.6 15 10 12.8 12.2 3.0 2.8 9.6 10.1 9.4 8.8 9.0 8.3 8.3 8.3

5 8.7 8.0 7.9 8.0 7.7 7.7 7.1 6.2 6.3 6.0 6.1 6.0 5.9 5.3 5.7 5.4 4.1 3.7 4.2 4.2 4.1 0 3.2

1. Three-year average. Source: OECD Health Statistics 2019. StatLink 2 https://doi.org/10.1787/888934016227

Figure 6.16. Thirty-day mortality after admission to hospital for ischaemic stroke based on linked data, 2007 and 2017 (or nearest year)

2007 2017 Age-sex standardised rate per 100 patients aged 45 years and over 30

25 28.2 20

15 20.5 17.3 16.4 15.8 10 14.8 14.0 12.3 12.0 12.2 11.6 11.4 9.8 9.4 9.3 10.2 10.3 10.3 9.3 8.7 10.0 5 8.5 6.2 0 5.7

1. Three-year average. 2. Results for Canada do not include deaths outside acute care hospitals. Source: OECD Health Statistics 2019. StatLink 2 https://doi.org/10.1787/888934016246

Figure 6.17. Variations across hospitals in 30-day mortality after admission for ischaemic stroke using linked and unlinked data, 2015-17

Note: The width of each line in the figure represents the number of hospitals (frequency) with the corresponding rate. Source: OECD Hospital Performance Data Collection 2019. StatLink 2 https://doi.org/10.1787/888934016265

HEALTH AT A GLANCE 2019 © OECD 2019 131 From: Health at a Glance 2019 OECD Indicators

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Please cite this chapter as:

OECD (2019), “Mortality following ischaemic stroke”, in Health at a Glance 2019: OECD Indicators, OECD Publishing, Paris.

DOI: https://doi.org/10.1787/a489af86-en

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