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Ontarians more likely to survive 1 year after hospitalization: study


Ontarians in 2009 were significantly more likely to survive one year after hospitalization than they were in 1994, after accounting for both increased patient sickness and improved survival in the general population, according to research conducted at the Institute for Clinical Evaluative Sciences (ICES) uOttawa and the Ottawa Hospital Research Institute (OHRI).

“This research shows that patients admitted to hospital in 2009 were significantly older, sicker and more acutely ill than in 1994,” said Dr. Carl van Walraven, a senior scientist at the Ottawa Hospital Research Institute and a scientist with ICES uOttawa. "However, after we corrected for these changes, people hospitalized in 2009 were 22 per cent less likely to die within the subsequent year.”

The study, published today in the CMAJ, analyzed the hospital records of more than 2.5 million Ontario adults and found significant improvement between 1994 and 2009 in survival of Ontarians admitted to hospital.

The population-based study examined the 1-year survival after admission to hospital for all adults admitted to hospital in Ontario, in 1994, 1999, 2004 and 2009 by linking to vital statistics data sets and found:

  • Compared to those from 1994, hospitalized people in 2009 were significantly more likely to die in 1 year (9.2 per cent to 11.6 per cent).
  • However, patients in 2009 were significantly older, sicker and more likely to have been admitted acutely by ambulance.
  • During this time, 1-year death risk in the general population decreased 24 per cent. After adjusting for important patient factors and the improved survival in the general population, death risk at 1 year in people admitted to hospital was significantly lower in 2009 than in 1994.

“When we combine this significant decrease in the risk of death with the fact that hospitalizations are so common, it is clear that there have been significant gains in life-years for Ontarians. Further research needs to be done on hospital admissions and mortality since the reasons for this improvement cannot be determined from this study,” says van Walraven.

The study “Trends in 1-year survival of people admitted to the hospital in Ontario, Canada: 1994-2009,” was published today in the CMAJ.

Authors: Carl van Walraven.

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy.

For the latest ICES news, follow us on Twitter: @ICESOntario

The Ottawa Hospital Research Institute (OHRI) is the research arm of The Ottawa Hospital and is an affiliated institute of the University of Ottawa, closely associated with the university’s Faculties of Medicine and Health Sciences. OHRI includes more than 1,700 scientists, clinical investigators, graduate students, postdoctoral fellows and staff conducting research to improve the understanding, prevention, diagnosis and treatment of human disease. Research at OHRI is supported by The Ottawa Hospital Foundation. www.ohri.caResearch

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