Impact of availability of direct-acting antivirals for hepatitis C on Canadian hospitalization rates, 2012-2016.

BACKGROUNDS: Hospitalizations associated with hepatitis C virus (HCV) infection and liver disease increased on average by 6.0% per year from 2004 to 2010 in Canada and were projected (in 2010) to increase by another 4% by 2016. The first generation of direct-acting antivirals (DAAs) became available in 2012. In 2014, a second generation of effective and well-tolerated DAA therapy was authorized in Canada. The impact of DAA therapy on the HCV-associated disease burden in Canada has not been documented. OBJECTIVES: To assess the potential impact of DAA therapy on the disease burden by a) comparing the actual hospitalization rates associated with HCV infection and liver disease following the introduction of DAAs in Canada with the 2010 baseline projection and b) documenting the associated uptake of anti-HCV therapy. METHODS: The hospital records of inpatients diagnosed with chronic HCV and chronic liver disease were extracted from the Canadian Discharge Abstract Database (DAD) by fiscal year for 2004-2016. We compared the actual number of hospitalizations to the baseline projection by year and for selected 5-year birth cohorts (1925-1989). The monthly number of new prescriptions for anti-HCV regimens was extracted from the IQVIA CDH CompuScript database (formerly IMS Health), aggregated to annual levels by age group and compared with hospitalization trends. RESULTS: Compared to the baseline projection, there was a slight reduction in hospitalizations in 2014/15 and 2015/16. This slight reduction was followed by a more significant decline in 2016/17 (32% below expected; 95% confidence interval [CI]: 27%-37%). The largest declines were observed for patients born before 1960 (age 55 or older) at 40% below expected in 2016/17. The number of new anti-HCV prescriptions increased from 5,484 in fiscal year 2012/13 to a peak of 17,775 in 2015/2016. The number of new prescriptions corresponds to approximately 1.3 and five times the number of hospitalizations in 2012/13 and 2015/16, respectively. CONCLUSIONS: In Canada there has been a modest decrease in HCV and liver-related hospitalizations following a significant increase in uptake of second-generation DAAs in 2015. However, the burden is still high. Linked health administrative databases created to monitor the disease burden in the new treatment era should provide additional insight with the linkage of treatment history and disease stage to individual outcomes.

Influenza-attributable deaths, Canada 1990-1999.

The number of deaths attributable to influenza is believed to be considerably higher than the number certified by vital statistics registration as due to influenza. Weekly mortality data for Canada from the 1989/1990 to the 1998/1999 influenza seasons were analysed by cause of death, age group, and place of death to estimate the impact of influenza on mortality. A Poisson regression model was found to accurately predict all-cause, as well as cause-specific mortality, as a function of influenza-certified deaths, after controlling for seasonality, and trend. Influenza-attributable deaths were calculated as predicted less baseline-predicted deaths. In summary, throughout the 1990s there were on average just under 4000 deaths attributable to influenza annually (for an influenza-attributable mortality rate of 13/100,000 persons), varying from no detectable excess mortality for the 1990/1991 influenza season, to 6000-8000 influenza-attributable deaths for the more severe influenza seasons of 1997/1998 and 1998/1999. On average, 8% (95% CI 7-10) of influenza-attributable deaths were certified as influenza, although this percentage varied from 4% to 12% from year to year. Only 15% of the influenza-attributable deaths were certified as pneumonia, and for all respiratory causes, 40%. Deaths were distributed over most causes. The weekly pattern of influenza-certified deaths was a good predictor of excess all-cause mortality.

Mutual concurrent validity of the child health questionnaire and the health utilities index: an exploratory analysis using survivors of childhood cancer.

Mutual concurrent validity of 2 generic measures of health-related quality of life (HRQL), the Child Health Questionnaire (CHQ) and the Health Utilities Index Mark 2 (HUI2) and HUI3, was assessed. Data were from 3 centers participating in a Canadian multi-center retrospective cohort study currently in progress to assess psycho-social and physical late effects in children surviving >/=5 years after cancer diagnosis between 1981 and 1990. Exploratory results are from 244 parent reports on HRQL in children <16 years old when studied. Spearman rank-order correlations between sub-scale scores for the CHQ and single-attribute utility scores for the corresponding attribute from the HUI2 and HUI3 were used. As predicted, the correlation between CHQ bodily pain and HUI2 and HUI3 pain was strong, 0.58 and 0.60, respectively, while correlations between CHQ physical functioning and HUI2 mobility and HUI3 ambulation were moderate, both 0.45. Correlations between CHQ mental health and HUI2 and HUI3 emotion were strong, 0.64 and 0.54, respectively, rather than moderate, as predicted. Both the CHQ general health scale and the general health single item were moderately correlated with the HUI2 and HUI3 global utility scores rather than weakly, as predicted (CHQ general health scale and HUI2 and HUI3 global utility were 0.43 and 0.44, respectively; CHQ general health single item and HUI2 and HUI3 global utility were 0. 38 and 0.42, respectively). The CHQ and HUI, which are based on different methodologies (summative Likert scaling and utility analysis, respectively), appear to capture similar constructs in childhood cancer survivors.

Kidney cancer in Canada: the rapidly increasing incidence of adenocarcinoma in adults and seniors.

PURPOSE: To examine kidney cancer incidence and mortality patterns since 1969 in Canada. METHOD: Linear regression of the log rates was used to estimate secular trends by age group and sex, and age-period-cohort models were fitted to examine changes in kidney cancer and renal adenocarcinoma incidence rates. RESULTS: A substantial increase in incidence rates was observed among those 35 years and older, with average increases of 2.5% or more annually for both sexes. Age-period-cohort modelling suggested that much of this increase resulted from a period effect. Changes in mortality were much more modest, especially among those aged 0-34, for whom mortality rates actually declined by an average of 4.2% and 5.4% annually for males and females respectively. CONCLUSIONS: Kidney cancer incidence rates have increased significantly, especially renal adenocarcinoma among adults and seniors. Diagnostic improvements and increasing levels of obesity in the Canadian population may have contributed to these trends.