Tobias Pilgaard Ottosen (Department of Clinical Epidemiology, Aarhus University Hospital, Denmark), in a presentation at European Stroke Conference (Nice, France, 6–9 May) told delegates that, over a 30-year period, first-time hospitalisation for subarachnoid haemorrhage has increased.
He said that, previous to this study, little was known about the secular trends in incidence and case-fatality of subarachnoid haemorrhage. In order to assess this, 30-year trends were examined for first-time hospitalisation and short- and long-term mortality for subarachnoid haemorrhage in Denmark.
In the nationwide, population-based cohort study 18,120 first-time patients were identified from 1983 to 2012 in the Danish National Registry of patients, according to Ottosen.
Speaking about the results, Ottosen said that the overall standardised incidence rate per 100,000 person-years over the 30-year period increased by 25% (from 12 to 15). For men, the increase in incidence was higher (from 10 to 13) than for women (from 14 to 16).
From these results and according to Ottosen, median age at first onset of subarachnoid haemorrhage has increased by approximately 10 years (from 53 to 62 years for men and 54 to 64 for women).
He also hightlighted that short- and long-term mortality declined substantially. Both 30-day, one-year and five-year mortality dropped from 38%, 44% and 51%, respectively in the period 1983–87 to 25%, 32% and 38%, respectively in the period 2008–2012. The reduction of approximately 13% in mortality was primary driven by a decline in short-term mortality.
Finally, he added that within the 30 years there were no major changes in the impact of comorbidity on mortality.
“The incidence of first-time hospitalisation for subarachnoid haemorrhage has increased accompanied by a substantial drop in 30-day, one-year and five-year mortality throughout the last 30-years in Denmark, and age at first onset of subarachnoid haemorrhage has increased by almost a decade,” said Ottosen in his conclusion.