title: Historical trends and projected hospital admissions for chronic hepatitis C infection in Canada: a birth cohort analysis.
abstract: BACKGROUND
  Much of the recent increase in hospital admission rates and mortality associated with hepatitis C in Canada is believed to be because of a higher prevalence of hepatitis C virus infection among those born between 1945 and 1965 (the baby boomer generation). We explored the effects of birth cohort on the rates of and projected trends in hospital admissions associated with hepatitis C.
  
  
  METHODS
  The hospital records of 17 344 inpatients with a diagnosis of chronic hepatitis C and liver disease, including liver cancer, were extracted from the Canadian Discharge Abstract Database for April 2004 to March 2011. For each 5-year birth cohort from 1915 to 1984, regression analysis was used to estimate the temporal trends associated with the average age of the cohort during the study period. Future hospital admissions were predicted based on the assumption that past trends would continue.
  
  
  RESULTS
  Hospital admissions associated with hepatitis C and liver disease increased an average of 6.0% (95% confidence interval [CI] 4.4%-7.7%) a year over the study period. As of 2010, hospital admission rates were highest for the 1950-1954 and 1955-1959 birth cohorts, at 17.6 (95% CI 13.2-23.5) and 13.7 (95% CI 10.3-18.2) times the rate for the 1970-1974 birth cohort. The corresponding same-age rate ratios predicted under a status quo scenario were 3.6 (95% CI 2.3-4.9) and 3.4 (95% CI 2.1-4.7). Same-age rate ratios were significantly higher for the four 5-year birth cohorts between 1950 and 1969 compared with other birth cohorts.
  
  
  CONCLUSIONS
  Hospital admissions associated with chronic hepatitis C and liver disease were significantly higher for the 1950-1954 and 1955-1959 birth cohorts than for most other birth cohorts. Without further interventions, the disease burden associated with hepatitis C will continue to increase for most birth cohorts, likely peaking after age 70 years. The substantial disease burden emerging in younger birth cohorts should be monitored.
authors.affiliation: Infectious Disease Prevention and Control Branch, Public Health Agency of Canada, Ottawa, Ont.
authors.forename: Dena L
authors.initials: DL
authors.lastname: Schanzer
authors.affiliation: Infectious Disease Prevention and Control Branch, Public Health Agency of Canada, Ottawa, Ont.
authors.forename: Dana
authors.initials: D
authors.lastname: Paquette
authors.affiliation: Department of Community Health Sciences, University of Manitoba, Winnipeg, Man.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Lix