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Impact of centralising acute stroke services in English metropolitan areas on mortality and length of hospital stay: difference-in-differences analysis

BMJ 2014; 349 doi: (Published 05 August 2014) Cite this as: BMJ 2014;349:g4757
  1. Stephen Morris, professor of health economics1,
  2. Rachael M Hunter, senior research associate2,
  3. Angus I G Ramsay, senior research associate1,
  4. Ruth Boaden, professor of service operations management3,
  5. Christopher McKevitt, reader4,
  6. Catherine Perry, research associate3,
  7. Nanik Pursani, patient representative5,
  8. Anthony G Rudd, professor of stroke medicine6,
  9. Lee H Schwamm, professor of neurology7,
  10. Simon J Turner, senior research associate1,
  11. Pippa J Tyrrell, professor of stroke medicine8,
  12. Charles D A Wolfe, professor of public health medicine49,
  13. Naomi J Fulop, professor of healthcare organisation and management1
  1. 1Department of Applied Health Research, University College London, London WC1E 7HB, UK
  2. 2Research Department of Primary Care and Population Health, University College London, London NW3 2PF, UK
  3. 3Manchester Business School, University of Manchester, Manchester M15 6PB, UK
  4. 4Division of Health and Social Care Research, School of Medicine, King’s College London, London SE1 3QD, UK
  5. 5King’s College London Stroke Research Patients and Family Group, Division of Health and Social Care Research, School of Medicine, King’s College London, London SE1 3QD, UK
  6. 6Guy’s and St Thomas’ NHS Foundation Trust, St Thomas’ Hospital, London SE1 7EH, UK
  7. 7Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
  8. 8University of Manchester Stroke and Vascular Centre, Manchester Academic Health Science Centre, Salford Royal Hospitals NHS Foundation Trust, Salford M6 8HD, UK
  9. 9National Institute of Health Research Comprehensive Biomedical Research Centre, Guy’s and St Thomas’ NHS Foundation Trust and King’s College London, London, UK
  1. Correspondence to: S Morris steve.morris{at}
  • Accepted 14 July 2014


Objective To investigate whether centralisation of acute stroke services in two metropolitan areas of England was associated with changes in mortality and length of hospital stay.

Design Analysis of difference-in-differences between regions with patient level data from the hospital episode statistics database linked to mortality data supplied by the Office for National Statistics.

Setting Acute stroke services in Greater Manchester and London, England.

Participants 258 915 patients with stroke living in urban areas and admitted to hospital in January 2008 to March 2012.

Interventions “Hub and spoke” model for acute stroke care. In London hyperacute care was provided to all patients with stroke. In Greater Manchester hyperacute care was provided to patients presenting within four hours of developing symptoms of stroke.

Main outcome measures Mortality from any cause and at any place at 3, 30, and 90 days after hospital admission; length of hospital stay.

Results In London there was a significant decline in risk adjusted mortality at 3, 30, and 90 days after admission. At 90 days the absolute reduction was −1.1% (95% confidence interval −2.1 to −0.1; relative reduction 5%), indicating 168 fewer deaths (95% confidence interval 19 to 316) during the 21 month period after reconfiguration in London. In both areas there was a significant decline in risk adjusted length of hospital stay: −2.0 days in Greater Manchester (95% confidence interval −2.8 to −1.2; 9%) and −1.4 days in London (−2.3 to −0.5; 7%). Reductions in mortality and length of hospital stay were largely seen among patients with ischaemic stroke.

Conclusions A centralised model of acute stroke care, in which hyperacute care is provided to all patients with stroke across an entire metropolitan area, can reduce mortality and length of hospital stay.


  • Contributors: SM, NJF, RMH and AIGR designed the study. SM carried out the analysis of the hospital episode statistics data and drafted the initial manuscript. AIGR carried out the analysis of the Stroke Improvement National Audit Programme data. RMH formatted the hospital episode statistics data and contributed to the statistical analysis. All authors made substantial contributions to the study design and interpretation of the findings and contributed to the drafting of the article or critical revision for important intellectual content, gave final approval of the version to be published, and agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the article are appropriately investigated and resolved. NJF is guarantor.

  • Funding: This paper presents independent research commissioned by the health services and delivery research programme of the National Institute for Health Research (NIHR), funded by the Department of Health (study reference 10/1009/09). The views expressed are those of the authors and not necessarily those of the NHS, the NIHR, or the Department of Health. CDAW was supported by the NIHR Biomedical Research Centre at Guy’s and St Thomas’ NHS Foundation Trust and King’s College London, and also by the NIHR Collaboration for Leadership in Applied Health Research and Care Funding scheme.

  • Competing interests: All authors have completed the ICMJE uniform disclosure form at and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years, and no other relationships or activities that could appear to have influenced the submitted work. AGR is the national clinical director of stroke in England, and London stroke clinical director. PJT was clinical lead for stroke in Greater Manchester up to 2013, and led the Greater Manchester stroke service redesign from 2007. The sponsor approved all aspects of the study protocol and any amendments thereto, but played no other role in design or conduct of the study.

  • Ethical approval: The study received ethical approval in September 2011 from the London East NHS research ethics committee (ref 11/LO/1396).

  • Data sharing: No additional data available.

  • Transparency statement: The last author (the manuscript’s guarantor) affirms that this manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as planned (and, if relevant, registered) have been explained.

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