Impact of reconfiguration of stroke services on mortality and length of hospital stay

Background and aim: In July 2010 a new multiple hub-and-spoke model for acute stroke care was implemented in London with 24/7 continuous specialist care during the first 72h to all stroke patients provided at 8 hyper-acute stroke units, and follow-up care provided in 24 stroke units. In April 2010 acute stroke services were reconfigured in Greater Manchester with hyper-acute care provided at a Comprehensive Stroke Centre (CSC) and two Primary Stroke Centres (PSCs). Individuals presenting within four hours of stroke are treated at the CSC or PSCs; those presenting outside this time are treated at one of 10 District Stroke Centres. Based on limited data a recent study found that the reconfiguration in London reduced mortality and costs per patient, predominately as a result of reduced hospital length of stay. Using national data we investigated the impact of both reconfigurations on mortality and length of hospital stay.

Methods: We analysed stroke-level Admitted Patient Care data from Hospital Episodes Statistics for England from 2008-2012 linked to ONS mortality data for all patients with a diagnosis of stroke (ICD-10 codes I61, I63 and I64). Outcomes were mortality at 72h, 30d and 90d after stroke and LOS. We regressed outcomes against time (before, during and after reconfiguration), region (London, Manchester, elsewhere), and interactions between time and region, controlling for age, gender, urban/rural classification, deprivation, ethnic group and stroke diagnosis. For mortality we used logistic regression; for LOS we modelled time to event (discharge) using survival analysis, accounting for death as a competing risk. We adjusted for clustering by provider. We calculated the between-area difference-in-difference of the predictive margins.

Results: In London after the reconfiguration there was an absolute reduction in 90d mortality of 0.9 percentage points (95% CI -1.7 to -0.1) and an absolute reduction in LOS of 0.9 days (95% CI -1.3 to -0.5). There were non-significant reductions in mortality at 72h (0.1 percentage points; 95% CI -0.4 to 0.2) and 30d (0.7 percentage points; 95% CI -1.5 to 0.03). In Manchester there was an absolute reduction in 72h mortality (0.5 percentage points; 95% CI -0.8 to -0.1) and 90d mortality (2.1 percentage points; 95% CI -3.0 to -1.2).  There were non-significant reductions in mortality at 30d (0.6 percentage points; 95% CI -1.4 to 0.3) and LOS (0.5 days; 95% CI -0.9 to 0.02).

Conclusions: The reconfiguration of acute stroke services in London was associated with significant reductions in mortality at 90d and LOS. Mortality in Greater Manchester also fell. Further reconfigurations of stroke services are proposed in Greater Manchester, to bring them more in line with the London model.