Supplementary Material for: Treatment of Aneurysmal Subarachnoid Haemorrhage in Germany: A Nationwide Analysis of the Years 2005-2009

<b><i>Background:</i></b> The aim of this study was to provide population-based nationwide rates of the different treatment modalities of aneurysmal subarachnoid haemorrhage (aSAH). <b><i>Methods:</i></b> German Diagnosis-Related Group data of the years 2005-2009 were used to calculate hospitalisation rates for intracranial aneurysm with aSAH. This study includes over 83 million hospitalisations. <b><i>Results:</i></b> We identified 15,768 hospitalisations with a diagnosis of aSAH. Throughout the observation period, the age-standardised rate for both sexes increased by 69% (95% confidence interval, CI 54-84) for coiling and 13% (95% CI 4-23) for clipping. The estimated annual percent change in the overall hospitalisation rate was 7.4% (95% CI 5.2-9.6). Age-standardised hospitalisation rates varied considerably by region. The estimated hospitalisation rate ratio of overall hospitalisation rates (East/West) was 0.86 (95% CI 0.80-0.91) for males and 0.81 (95% CI 0.77-0.85) for females. After adjustment for age and co-morbidity, the hazard ratio (HR) for in-hospital mortality was higher for coiling than clipping (HR = 1.12, 95% CI 1.01-1.23). Patients who received coiling or clipping had ventricular shunt placement in 5.0 (n = 819) and 6.1% (n = 998), respectively. The estimated length of stay was 3.3 days (95% CI 2.56-4.05) shorter for coiling than clipping. <b><i>Conclusions:</i></b> We provide for the first time nationwide, representative hospitalisation rates for the treatment of aSAH. Our results indicate a change in the practice pattern for Germany during the observation period. We observed a gradual increase in overall hospitalisation rates for aSAH.