The hospitalization rate for mental illness in Canada stayed largely unchanged in 2004-05 compared with the year before, according to a report released Tuesday.

The analysis in brief from the Canadian Institute for Health Information combined data from psychiatric and general hospitals.

About 20 per cent of people will experience mental illness during their lifetimes, and the rest of the population will be affected by an illness in family members, friends or colleagues, according to an earlier study by the institute called A Report on Mental Illness in Canada.

Canadian hospitals reported 147,642 separations, defined as the discharge or death of a hospitalized patient, related to mental illness in 2004-05, the latest report said. Since separations count events rather than patients, someone who is admitted and discharged three times during a year would be counted as three separations.

The figure translates to 605 hospitalizations per 100,000 population, which is about the same as the the 607 separations per 100,000 population reported in 2003-04, the institute said.

On average, patients with mental illness stayed in Canadian general hospitals for almost 16 days, the report said.

Although psychiatric hospitals accounted for about 13 per cent of mental illness separations, patients admitted to the specialized facilities stayed longer.

The average length of stay for psychiatric hospitals was almost 109 days, compared with almost 17 days for general hospitals, the report's authors said.

The report also includes the number and rate of separations by province in 2004-05. Data from psychiatric hospitals in Quebec was not available.