Long-term projections of cancer incidence and mortality in Canada: The OncoSim All Cancers Model.

Using the OncoSim All Cancers Model, we estimated the annual cancer incidence, mortality and cancer management costs in Canada from 2020 to 2040. Incidence for each cancer type was estimated from logistic regression analyses of the Canadian Cancer Registry (1992-2017), with province/territory, sex, five-year age groups and year as covariates. Deaths were estimated by sex and tumour site for cancers diagnosed between 2000 and 2017 (deaths to the end of 2017). The total cost of a cancer type was the sum of costs for individuals across four phases of cancer care. The projections presented in this study were generated based on a simulation of 32 million cases. The OncoSim All Cancers Model projects a 40% increase in the overall number of incident cancer cases from 2020 to 2040. The number of the four most commonly diagnosed cancers in Canada (breast, colorectal, lung, and prostate) are projected to increase annually. The overall number of cancer deaths is projected to increase by 44% from 2020 to 2040. More cancer deaths are projected in males than in females. The age-standardized mortality rate is expected to remain relatively stable over time. Overall cancer management costs are projected to increase from $20.6B in 2020 to $31.4B in 2040. Due mainly to an aging population and population growth in Canada, we estimate that cancer incidence, mortality and cancer management costs will increase considerably between 2020 and 2040. These results highlight the importance of planning for increasing investment and capacity in cancer control.

Prevalence of prescription and non-prescription polypharmacy by frailty and sex among middle-aged and older Canadians.

Background: Estimates of polypharmacy have primarily been derived from prescription claims, and less is known about the use of non-prescription medications (alone or in combination with prescription medications) across the frailty spectrum or by sex. Our objectives were to estimate the prevalence of polypharmacy (total, prescription, non-prescription, and concurrent prescription and non-prescription) overall, and by frailty, sex and broad age group. Data: Canadian Health Measures Survey, Cycle 5, 2016 to 2017. Methods: Among Canadians aged 40 to 79 years, all prescription and non-prescription medications used in the month prior to the survey were documented. Polypharmacy was defined as using five or more medications total (prescription and non-prescription), prescription only and non-prescription only. Concurrent prescription and non-prescription use was defined as two or more and three or more of each. Frailty was defined using a 31-item frailty index (FI) and categorized as non-frail (FI ≤ 0.1) and pre-frail or frail (FI > 0.1). Survey-weighted descriptive statistics were calculated overall and age standardized. Results: We analyzed 2,039 respondents, representing 16,638,026 Canadians (mean age of 56.9 years; 51% women). Overall, 52.4% (95% confidence interval [CI] = 47.3 to 57.4) were defined as pre-frail or frail. Age-standardized estimates of total polypharmacy, prescription polypharmacy and concurrent prescription and non-prescription medication use were significantly higher among pre-frail or frail versus non-frail adults (e.g., total polypharmacy: 64.1% versus 31.8%, respectively). Polypharmacy with non-prescription medications was common overall (20.5% [95% CI = 16.1 to 25.8]) and greater among women, but did not differ significantly by frailty. Interpretation: Polypharmacy and concurrent prescription and non-prescription medication use were common among Canadian adults, especially those who were pre-frail or frail. Our findings highlight the importance of considering non-prescribed medications when measuring the exposure to medications and the potential risk for adverse outcomes.

The Burden of Health-Related Out-of-Pocket Cancer Costs in Canada: A Case-Control Study Using Linked Data.

BACKGROUND: The burden of out-of-pocket costs among cancer patients/survivors in Canada is not well understood. The objective of this study was to examine the health-related out-of-pocket cost burden experienced by households with a cancer patient/survivor compared to those without, examine the components of health-related costs and determine who experiences a greater burden. DATA AND METHODS: This study used a data linkage between the Survey of Household Spending and the Canadian Cancer Registry to identify households with a cancer patient/survivor (cases) and those without (controls). The out-of-pocket burden (out-of-pocket costs measured relative to household income) and mean costs were described and regression analyses examined the characteristics associated with the household out-of-pocket burden and annual out-of-pocket costs. RESULTS: The health-related out-of-pocket cost burden and annual costs measured in households with a cancer patient/survivor were 3.08% (95% CI: 2.55-3.62%) and CAD 1600 (95% CI: 1456-1759), respectively, compared to a burden of 2.84% (95% CI: 2.31-3.38) and annual costs of CAD 1511 (95% CI: 1377-1659) measured in control households, respectively. Households with a colorectal cancer patient/survivor had a significantly higher out-of-pocket burden compared to controls (mean difference: 1.0%, 95% CI: 0.18, 0.46). Among both cases and controls, the lowest income quintile households experienced the highest health-related out-of-pocket cost burden. INTERPRETATION: Within a universal health care system, it is still relevant to monitor health-related out-of-pocket spending that is not covered by existing insurance mechanisms; however, this is not routinely assessed in Canada. We demonstrate the feasibility of measuring such costs in households with a cancer patient/survivor using routinely collected data. While the burden and annual health-related out-of-pocket costs of households with a cancer patient/survivor were not significantly higher than control households in this study, the routine measurement of out-of-pocket costs in Canada could be systemized, providing a novel, system-level, equity-informed performance indicator, which is relevant for monitoring inequities in the burden of out-of-pocket costs.

The OncoSim-Breast Cancer Microsimulation Model.

BACKGROUND: OncoSim-Breast is a Canadian breast cancer simulation model to evaluate breast cancer interventions. This paper aims to describe the OncoSim-Breast model and how well it reproduces observed breast cancer trends. METHODS: The OncoSim-Breast model simulates the onset, growth, and spread of invasive and ductal carcinoma in situ tumours. It combines Canadian cancer incidence, mortality, screening program, and cost data to project population-level outcomes. Users can change the model input to answer specific questions. Here, we compared its projections with observed data. First, we compared the model's projected breast cancer trends with the observed data in the Canadian Cancer Registry and from Vital Statistics. Next, we replicated a screening trial to compare the model's projections with the trial's observed screening effects. RESULTS: OncoSim-Breast's projected incidence, mortality, and stage distribution of breast cancer were close to the observed data in the Canadian Cancer Registry and from Vital Statistics. OncoSim-Breast also reproduced the breast cancer screening effects observed in the UK Age trial. CONCLUSIONS: OncoSim-Breast's ability to reproduce the observed population-level breast cancer trends and the screening effects in a randomized trial increases the confidence of using its results to inform policy decisions related to early detection of breast cancer.

All-cause acute care hospitalization rates of immigrants and the Canadian-born population: A linkage study.

BACKGROUND: As Canadian immigration levels increase, knowledge concerning immigrant health becomes increasingly important for health system policy and planning. This study compares the rate of all-cause hospitalization among immigrants with that of their Canadian-born counterparts. DATA AND METHODS: Using records from the Discharge Abstract Database (2004/2005 to 2016/2017) and the Ontario Mental Health Reporting System (2006/2007 to 2017/2018) linked to the 2016 Longitudinal Immigration Database, this study compared the age-standardized hospitalization rates (ASHRs) among immigrants with those of the Canadian-born population; the latter were obtained from a linkage based on the 2011 National Household Survey. Comparisons were made at the International Classification of Diseases chapter level by immigrant landing year, admission category and world region of birth. Quebec data were not available. RESULTS: Overall, ASHRs among immigrants were lower than for the Canadian-born population. Immigrants in the economic class had the lowest ASHR, followed by those in the family class and among refugees. After pregnancy was excluded, leading hospitalization causes were similar for immigrants and the Canadian-born population, where top causes included digestive system and circulatory diseases, injuries, and cancer. In male and female immigrants, the ASHRs were lowest among those from East Asia. By landing year, males arriving earlier had the highest ASHR compared with the most recent arrivals. When pregnancy was excluded and while the differential in ASHRs among females by landing year remained, the magnitude was smaller. INTERPRETATION: These results corroborate those from previous studies suggesting a healthy immigrant effect, but also reveal heterogeneity in ASHRs within the immigrant population. They provide a baseline for comparison of health status between populations, which enables further monitoring and informs health-system policy and planning.

Associations between the receipt of inpatient palliative care and acute care outcomes: A retrospective study.

BACKGROUND: Palliative care (PC) has been shown to improve outcomes for individuals at the end of life. Despite this, many Canadians do not receive PC prior to death. The present study examines the receipt of inpatient PC and its association with location of death, as well as with admission to intensive care units (ICUs) and use of alternate level of care (ALC) beds in hospital in the last 30 days of life. DATA AND METHODS: The study sample is a retrospective cohort of adult Canadians (aged 19 and older) who died between April 1, 2010, and December 31, 2014. Deaths were ascertained from the Canadian Vital Statistics Database and linked to hospitalizations records in the Discharge Abstract Database to identify the receipt of inpatient PC. RESULTS: More than half (57.7%) of Canadian adults died in hospital, with only 12.6% receiving any inpatient PC in the year prior to death, and 1.7% receiving a preterminal PC designation (i.e., PC initiated prior to the last 30 days of life). In the adjusted analyses, receipt of any inpatient PC was associated with a higher likelihood of death in hospital but lower odds of ICU admission. Pre-terminal PC was associated with lower odds of death in hospital, ICU admission and ALC bed use. DISCUSSION: This study offers new insights into the association between inpatient PC and outcomes at the end of life among Canadians. Future studies could expand on these observations to further understanding of the role of inpatient PC in the end-of-life experience for different populations in Canada.

Associations between cadmium levels in blood and urine, blood pressure and hypertension among Canadian adults.

BACKGROUND: Cadmium has been inconsistently related to blood pressure and hypertension. The present study seeks to clarify the relationship between cadmium levels found in blood and urine, blood pressure and hypertension in a large sample of adults. METHODS: The study sample included participants ages 20 through 79 from multiple cycles of the Canadian Health Measures Survey (2007 through 2013) with measured blood cadmium (n=10,099) and urinary cadmium (n=6988). Linear regression models examined the association between natural logarithm transformed cadmium levels and blood pressure (separate models for systolic and diastolic blood pressure) after controlling for known covariates. Logistic regression models were used to examine the association between cadmium and hypertension. Models were run separately by sex, smoking status, and body mass index category. RESULTS: Men had higher mean systolic (114.8 vs. 110.8mmHg, p<0.01) and diastolic (74.0 vs. 69.6mmHg, p<0.01) blood pressure compared to women. Although, geometric mean blood (0.46 vs. 0.38µg/L, p<0.01) and creatinine-adjusted standardized urinary cadmium levels (0.48 vs. 0.38µg/L, p<0.01) were higher among those with hypertension, these differences were no longer significant after adjustment for age, sex and smoking status. In overall regression models, increases in blood cadmium were associated with increased systolic (0.70mmHg, 95% confidence interval [CI]=0.25-1.16, p<0.01) and diastolic blood pressure (0.74mmHg, 95% CI=0.30-1.19, p<0.01). The associations between urinary cadmium, blood pressure and hypertension were not significant in overall models. Model stratification revealed significant and negative associations between urinary cadmium and hypertension among current smokers (OR=0.61, 95% CI=0.44-0.85, p<0.01), particularly female current smokers (OR=0.52, 95% CI=0.32-0.85, p=0.01). CONCLUSION: This study provides evidence of a significant association between cadmium levels, blood pressure and hypertension. However, the significance and direction of this association differs by sex, smoking status, and body mass index category.

Cadmium levels and sources of exposure among Canadian adults.

BACKGROUND: Cadmium is a heavy metal found naturally in the environment that has been associated with negative health outcomes. The present study examines levels of blood cadmium (BCd), urinary cadmium (UCd), and the main sources of cadmium exposure among Canadians aged 20 to 79. DATA AND METHODS: The data are from cycles 1 (2007 to 2009) and 2 (2009 to 2011) of the Canadian Health Measures Survey (CHMS), including measures of BCd and UCd, markers of smoking status (self-reported and second-hand smoke exposure), and self-reported consumption of foods known to be high in cadmium. The relationship between sources of exposure and cadmium levels was examined descriptively. The magnitude of the contribution of different exposure sources was examined in regression models. RESULTS: Age and smoking status were the greatest contributors to BCd and UCd: older people and current smokers had the highest cadmium levels. Dietary exposure, while significant, was a modest contributor overall, but a more important source of cadmium among never-smokers. INTERPRETATION: Smoking was the greatest contributor to cadmium levels among Canadians aged 20 to 79. Dietary differences explained a small percentage of variation in cadmium levels.

Dynamics of smoking cessation and health-related quality of life among Canadians.

BACKGROUND: People who smoke are at increased risk of lung and other cancers, heart attack, stroke, chronic lung disease and premature death. After smoking cessation, these risks diminish, but little is known about the time required to regain the level of health of people who have never smoked. This analysis describes trajectories of health-related quality of life (HRQL) in relation to smoking status, focusing on the time required for former smokers to achieve an HRQL level similar to that of never-smokers. METHODS: Data were from nine cycles (1994/1995 through 2010/2011) of the National Population Health Survey. Analyses were based on longitudinal data for 3,341 men and 4,143 women aged 40 or older in 1994/1995. Multi-level growth modelling was used to describe HRQL trajectories over the 16-year follow-up period in relation to smoking status, which was updated every two years. RESULTS: Across all ages and for both sexes, persistent smokers had lower HRQL than did never-smokers. Among men, HRQL improved after 5 years of quitting; after 20 years, HRQL was similar to that of never-smokers. Among women, after 10 years of cessation, the HRQL of former smokers was clinically similar to that of those who had never smoked. INTERPRETATION: At any age, and for both men and women, long-term smoking cessation results in improvements in HRQL.

Health among caregivers of children with health problems: findings from a Canadian population-based study.

OBJECTIVES: We used population-based data to evaluate whether caring for a child with health problems had implications for caregiver health after we controlled for relevant covariates. METHODS: We used data on 9401 children and their caregivers from a population-based Canadian study. We performed analyses to compare 3633 healthy children with 2485 children with health problems. Caregiver health outcomes included chronic conditions, activity limitations, self-reported general health, depressive symptoms, social support, family functioning, and marital satisfaction. Covariates included family (single-parent status, number of children, income adequacy), caregiver (gender, age, education, smoking status, biological relationship to child), and child (age, gender) characteristics. RESULTS: Logistic regression showed that caregivers of children with health problems had more than twice the odds of reporting chronic conditions, activity limitations, and elevated depressive symptoms, and had greater odds of reporting poorer general health than did caregivers of healthy children. CONCLUSIONS: Caregivers of children with health problems had substantially greater odds of health problems than did caregivers of healthy children. The findings are consistent with the movement toward family-centered services recognizing the link between caregivers' health and health of the children for whom they care.

Changes in the prevalence of asthma among Canadian children.

The prevalence of childhood asthma is rising, particularly among boys, among 0- to 5-year-olds and 10- to 11-year-olds, and among children in households where adults smoke. Whether the increase is due to an improvement in physicians' ability to recognize and diagnose asthma, or whether the underlying causes are becoming more widespread, cannot be determined from this analysis and warrant further study.