A lack of association between increases in gastrointestinal, liver, and urologic cancers and cyanobacterial contamination of fresh water lakes in Manitoba.

Cyanobacteria or blue-green algae are becoming increasingly abundant in North American fresh water lakes. Toxins produced by cyanobacteria have been associated with gastrointestinal injury, liver failure, and nephrotoxicity. They have also been implicated in the pathogenesis of gastrointestinal and liver cancers. The purpose of the present study was to determine whether the incidence rates of gastrointestinal, liver, and urologic cancers are increasing in the province of Manitoba and, if so, whether these increases spatially and/or temporally correlate with areas where cyanobacterial contamination of fresh water lakes have been identified. Cancer incidence data were obtained from the Manitoba Cancer Registry. Cyanobacterial contamination data, as reflected by microcystin toxin concentrations, were available from the Manitoba Water Stewardship. ArcGIS mapping was employed to document spatial and temporal relationships between cancer incidence and cyanobacterial data. The results revealed that although the incidence rates for all three cancers have increased over the past 20-25 years, these increases were not disproportionally higher in zones with high microcystin toxin determinations. The results of this study argue against increased exposure to cyanotoxins as an explanation for the increase in gastrointestinal, liver and urologic cancers in Manitoba.

Examining the impact of a province-wide physical education policy on secondary students' physical activity as a natural experiment.

BACKGROUND: The purpose of this paper is to examine the impact of a province-wide physical education (PE) policy on secondary school students' moderate to vigorous physical activity (MVPA). METHODS: Policy: In fall 2008, Manitoba expanded a policy requiring a PE credit for students in grades 11 and 12 for the first time in Canada. The PE curriculum requires grades 11 and 12 students to complete a minimum of 55 h (50% of course hours) of MVPA (e.g., ≥30 min/day of MVPA on ≥5 days a week) during a 5-month semester to achieve the course credit. STUDY DESIGNS: A natural experimental study was designed using two sub-studies: 1) quasi-experimental controlled pre-post analysis of self-reported MVPA data obtained from census data in intervention and comparison [Prince Edward Island (PEI)] provinces in 2008 (n = 33,619 in Manitoba and n = 2258 in PEI) and 2012 (n = 41,169 in Manitoba and n = 4942 in PEI); and, 2) annual objectively measured MVPA in cohorts of secondary students in intervention (n = 447) and comparison (Alberta; n = 224) provinces over 4 years (2008 to 2012). ANALYSIS: In Study 1, two logistic regressions were conducted to model the odds that students accumulated: i) ≥30 min/day of MVPA, and ii) met Canada's national recommendation of ≥60 min/day of MVPA, in Manitoba versus PEI after adjusting for grade, sex, and BMI. In Study 2, a mixed effects model was used to assess students' minutes of MVPA per day per semester in Manitoba and Alberta, adjusting for age, sex, BMI, school location and school SES. RESULTS: In Study 1, no significant differences were observed in students achieving ≥30 (OR:1.13, 95% CI:0.92, 1.39) or ≥60 min/day of MVPA (OR:0.92, 95% CI: 0.78, 1.07) from baseline to follow-up between Manitoba and PEI. In Study 2, no significant policy effect on students' MVPA trajectories from baseline to last follow-up were observed between Manitoba and Alberta overall (-1.52, 95% CI:-3.47, 0.42), or by covariates. CONCLUSIONS: The Manitoba policy mandating PE in grades 11 and 12 had no effect on student MVPA overall or by key student or school characteristics. However, the effect of the PE policy may be underestimated due to the use of a nonrandomized research design and lack of data assessing the extent of policy implementation across schools. Nevertheless, findings can provide evidence about policy features that may improve the PE policy in Manitoba and inform future PE policies in other jurisdictions.

Comparison of outcome of patients with CLL who are referred or nonreferred to a specialized CLL clinic: a Canadian population-based study.

Chronic lymphocytic leukemia and small lymphocytic lymphoma (CLL/SLL) patients in Manitoba are either referred to the CLL Clinic at CancerCare Manitoba (CCMB) or are followed by other hematologists and general practitioners. However, it has been unclear whether referral to the CLL clinic influences patient outcome. Overall survival (OS) was assessed for all CLL/SLL patients diagnosed in Manitoba between 2007 and 2011. Of 555 patients, 281 (51%) were referred to the CLL clinic. Patients seen in this clinic had a twofold increased OS compared to patients who were managed by other hematologists and general practitioners (HR 2.375, P 0.0002) when adjusted for age, gender, presence of pre- or post-CLL cancer, treatment and urban/rural location. In the nonreferred population there was a striking correlation between advancing age and decreasing OS. However, this correlation was almost eliminated in the referred population who were more likely to receive chemotherapy. Patients referred and seen in the CLL clinic have an improved OS compared to nonreferred patients and this appears to be primarily related to improved OS in the elderly. Possible explanations for this finding are discussed.

The Geographic Distribution of Liver Cancer in Canada Does Not Associate with Cyanobacterial Toxin Exposure.

BACKGROUND: The incidence of liver cancer has been increasing in Canada over the past decade, as has cyanobacterial contamination of Canadian freshwater lakes and drinking water sources. Cyanotoxins released by cyanobacteria have been implicated in the pathogenesis of liver cancer. OBJECTIVE: To determine whether a geographic association exists between liver cancer and surrogate markers of cyanobacterial contamination of freshwater lakes in Canada. METHODS: A negative binomial regression model was employed based on previously identified risk factors for liver cancer. RESULTS: No association existed between the geographic distribution of liver cancer and surrogate markers of cyanobacterial contamination. As predicted, significant associations existed in areas with a high prevalence of hepatitis B virus infection, large immigrant populations and urban residences. DISCUSSION AND CONCLUSIONS: The results of this study suggest that cyanobacterial contamination of freshwater lakes does not play an important role in the increasing incidence of liver cancer in Canada.

Mammography rates for breast cancer screening: a comparison of First Nations women and all other women living in Manitoba, Canada, 1999-2008.

INTRODUCTION: First Nations (FN) women historically have low rates of preventive care, including breast cancer screening. We describe the frequency of breast cancer screening among FN women living in Manitoba and all other Manitoba (AOM) women after the introduction of a provincial, organized breast screening program and explore how age, area of residence, and time period influenced breast cancer screening participation. METHODS: The federal Indian Registry was linked to 2 population-based, provincial data sources. A negative binomial model was used to compare breast cancer screening for FN women with screening for AOM women. RESULTS: From 1999 through 2008, 37% of FN and 59% of AOM women had a mammogram in the previous 2 years. Regardless of area of residence, FN women were less likely to have had a mammogram than AOM women (relative rate [RR] = 0.69 in the north, RR = 0.55 in the rural south, and RR = 0.53 in urban areas). CONCLUSIONS: FN women living in Manitoba had lower mammography rates than AOM women. To ensure equity for all Manitoba women, strategies that encourage FN women to participate in breast cancer screening should be promoted.

Colorectal cancer screening in first nations people living in Manitoba.

BACKGROUND: Because the burden of colorectal cancer (CRC) seems to be increasing in First Nations, it is important to better understand CRC screening utilization. The objective of this study was to describe CRC screening among First Nations living in Manitoba. METHODS: The Federal Indian Register was linked to two provincial databases. A negative binomial model was used to compare the probability of First Nations having a fecal occult blood test (FOBT), colonoscopy, or flexible sigmoidoscopy (FS) with all other Manitobans. RESULTS: First Nations who lived in Winnipeg were significantly less likely to have had a FOBT in the previous 2 years than all other Manitobans who lived in Winnipeg [rate ratio (RR) = 0.40; 95% confidence intervals (CI), 0.37-0.44]. There was no difference in the likelihood of having a colonoscopy or FS for First Nations individuals who resided in northern Manitoba compared with all other Manitobans (RR, 1.04; 95% CI, 0.91-1.19). However, First Nations who lived in the rural south or urban areas were less likely than all other Manitobans to have had a colonoscopy or FS (RR, 0.81, 95% CI, 0.75-0.87, rural south; RR, 0.86, 95% CI, 0.81-0.92, urban). CONCLUSIONS: First Nations living in Winnipeg were significantly less likely to be screened for CRC using the FOBT. Colonoscopy and FS use depended on area of residence. IMPACT: First Nations experience barriers that impede the use of CRC screening. Further research is needed to understand these barriers to extend the benefit of CRC screening to this population. Cancer Epidemiol Biomarkers Prev; 24(1); 241-8. ©2014 AACR.

Pap test use and cervical cancer incidence in First Nations women living in Manitoba.

This study examined Papanicolaou (Pap) test utilization, Pap test results, and cervical cancer incidence among First Nations (FN) women living in Manitoba, Canada taking into account age group, time period, and area of residence. Six population-based data sources were linked at an individual level. Negative binomial regression was used to compare Pap test utilization and results between FN and all other Manitoba (AOM) women. Poisson regression was used to compare cervical cancer incidence. Among women younger than 25 years, FN were more likely than AOM women to have had a Pap test [rate ratio (RR) = 1.37, 95% confidence intervals (CI), 1.22-1.53, 18-19 year olds; RR = 1.17, 95% CI, 1.05-1.31, 20-24 year olds]. There was no difference in Pap test use for women 25 to 29 or 30 to 39 years. FN 40 years and older were less likely to have a Pap test than AOM women (RR = 0.84, 95% CI, 0.75-0.93, 40-49 years old; RR = 0.71, 95% CI, 0.63-0.79, 50-59 years old; RR = 0.59, 95% CI, 0.52-0.66, 60-69 years old). FN were more likely than AOM women to have a high (RR = 1.88, 95% CI, 1.65-2.13) or low-grade Pap test result (RR = 1.60, 95% CI, 1.48-1.73). The invasive cervical cancer incidence rate was double for FN women 25 to 39 years of age (21.9 per 100,000, FN; 10.2 per 100,000, AOM, P = 0.006) and 40 to 69 years of age (24.3 per 100,000, FN; 12.3 per 100,000, AOM, P = 0.007). In conclusion, cervical cancer screening among FN women over 40 years of age must be increased to address the higher cervical cancer incidence.

Geographical variation and factors associated with colorectal cancer mortality in a universal health care system.

OBJECTIVE: To investigate the geographical variation and small geographical area level factors associated with colorectal cancer (CRC) mortality. METHODS: Information regarding CRC mortality was obtained from the population-based Manitoba Cancer Registry, population counts were obtained from Manitoba's universal health care plan Registry and characteristics of the area of residence were obtained from the 2001 Canadian census. Bayesian spatial Poisson mixed models were used to evaluate the geographical variation of CRC mortality and Poisson regression models for determining associations with CRC mortality. Time trends of CRC mortality according to income group were plotted using joinpoint regression. RESULTS: The southeast (mortality rate ratio [MRR] 1.31 [95% CI 1.12 to 1.54) and southcentral (MRR 1.62 [95% CI 1.35 to 1.92]) regions of Manitoba had higher CRC mortality rates than suburban Winnipeg (Manitoba's capital city). Between 1985 and 1996, CRC mortality did not vary according to household income; however, between 1997 and 2009, individuals residing in the highest-income areas were less likely to die from CRC (MRR 0.77 [95% CI 0.65 to 0.89]). Divergence in CRC mortality among individuals residing in different income areas increased over time, with rising CRC mortality observed in the lowest income areas and declining CRC mortality observed in the higher income areas. CONCLUSIONS: Individuals residing in lower income neighbourhoods experienced rising CRC mortality despite residing in a jurisdiction with universal health care and should receive increased efforts to reduce CRC mortality. These findings should be of particular interest to the provincial CRC screening programs, which may be able to reduce the disparities in CRC mortality by reducing the disparities in CRC screening participation.

Trends in time to diagnosis of colon cancer and impact on clinical outcomes.

BACKGROUND: There has been a rapid increase in screening for colorectal cancer (CRC) over the past several years in North America. This could paradoxically lead to worsening outcomes if the system is not adapted to deal with the increased demand. For example, this could create increased wait times for endoscopy and delayed time to CRC diagnosis, which could worsen clinical outcomes such as stage at diagnosis and/or survival. No previous Canadian study has evaluated the association between time to CRC diagnosis and clinical outcomes. METHODS: The present historical cohort study used Manitoba's population-based cancer registry and Manitoba Health administrative databases. The effect of time to diagnosis on patient survival was evaluated using Cox regression analysis with adjustment for stage at diagnosis, grade of CRC, age, sex, socioeconomic status, comorbidity index score and year of CRC diagnosis. The association between time to diagnosis and CRC stage at diagnosis was evaluated using multivariate logistic regression analysis. RESULTS: The median time to CRC diagnosis increased significantly from 72 days (95% CI 61 days to 83 days) in 2004 to 105 days (95% CI 64 days to 129 days) in the first three months of 2009 (P=0.04). There was no significant association between time to diagnosis and survival. Individuals with the longest time to diagnosis were less likely to have stage III/IV CRC at diagnosis (quartile 4 versus quartile 1: OR 0.50 [95% CI 0.33 to 0.75). CONCLUSION: Time to CRC diagnosis is continuing to increase in Manitoba. Although the present study did not detect a significant negative clinical effect of increasing time to diagnosis, additional studies are required.

Providing palliative care in the ambulatory care setting.

Palliative care that provides specialized attention to pain and symptom management is important for patients with cancer. Palliative care aims to reduce pain and other symptoms through an interdisciplinary approach involving physicians, nurses, social workers, and other members of the healthcare team. Families are included in care planning. Patients and families benefit from the availability of palliative care services early in the disease process, particularly when symptoms impact quality of life. One way to implement early palliative interventions is the establishment of an ambulatory care clinic dedicated to palliative care. This article describes the experience of an outpatient palliative care clinic at a large teaching hospital by using case studies to highlight the benefits of ambulatory palliative care and concluding with recommendations for research.