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.Interpretation: 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 Abstract E140CMAJ OPEN, 2(3) ResearchCMAJ OPEN people who had tested positive for HCV compared with those who had tested negative.

Identifying and describing a cohort effect in the national database of reported cases of hepatitis C virus infection in Canada (1991-2010): an age-period-cohort analysis

“…The scope of our findings is generally in line with the cohort effect previously described in first-time blood donors 15 and hospital patients 23 in Canada. The possible explanations for the observed findings include past exposure to injection drug use, blood transfusions before the introduction of universal HCV screening, other invasive procedures in health care settings, tattooing and high-risk sexual exposure among people with compromised immune systems and people co-infected with sexually transmitted infections.…”

“…Our analysis adds to what is already known about the HCV cohort effect in Canadian baby boomers 15,23 by using nationally representative case report data for HCV infection and will support public health efforts to address the needs of the populations affected by HCV.…”

Estimated prevalence of Hepatitis C Virus infection in Canada, 2011

“…The use of the two data sets through an iterative process improved the overall model and made it less dependent on the limitations of any one data set. We also cross-validated the annual HCV prevalence predicted by the model with the prevalence from independent data sources, including the Canadian Health Measures Survey 2007-2011 data (7) and the reported HCV infections among healthcare patients from the CIHI Discharge Abstract Database (29). While absolute measures of HCV prevalence differed between the above data sources (possibly due to the differences in methodology and in how outcomes and geographic representation were defined) there was general agreement in the distribution of predicted/estimated HCV prevalent cases by year of report and birth cohort as well as for temporal trends.…”

The management of chronic hepatitis C: 2018 guideline update from the Canadian Association for the Study of the Liver

“…4 Although the overall prevalence of chronic hepatitis C is declin ing, complications of the disease are increasing because of aging of the infected population and progression of liver fibrosis. [1][2][3] Mod elling data suggest that if nothing is done to change the current situation, cases of decompensated cirrhosis, hepatocellular car cinoma and liverrelated mortality will increase by 80%, 205% and 160%, respectively, by 2035 compared with 2013 levels. 2 The primary objective of antiHCV therapy is complete eradica tion of the virus, termed a sustained virologic response, which is defined as absence of viremia 12 weeks after completion of ther apy.…”

“…[1][2][3] A recent modelling study suggested that about 252 000 Canadians (uncertainty interval: 178 000-315 000 Can adians) were chronically infected in 2013. The birth cohort of has the highest prevalence of chronic HCV infection, yet it is estimated that up to 70% of this group have not been tested for HCV.…”