The benefits of sportfish consumption and omega-3 fatty acid (omega3-FA) intake for cardiovascular risk factors were evaluated in a sample of 112 male fishers from the St. Lawrence River in the Montreal area during the 1996 winter and fall fishing seasons. A questionnaire on fishing practices and fish consumption was administered, and fasting blood samples were collected for lipid and phospholipid determination. Linear regression analyses, which considered the confounding effect of major risk factors, did not show any significant association between measured omega3-FAs or reported fish intake and blood lipids or blood pressure. This study is limited by its low statistical power due to the small sample size and the possibility that the fish eaten by the participants were low in omega3-FAs or that the participants diets contained foods high in cholesterol-raising fat.
Little attention has been devoted to the effects on children's respiratory health of exposure to sulphur dioxide (SO2) in ambient air from local industrial emissions. Most studies on the effects of SO(2) have assessed its impact as part of the regional ambient air pollutant mix.
To examine the association between exposure to stack emissions of SO(2) from petroleum refineries located in Montreal's (Quebec) east-end industrial complex and the prevalence of active asthma and poor asthma control among children living nearby.
The present cross-sectional study used data from a respiratory health survey of Montreal children six months to 12 years of age conducted in 2006. Of 7964 eligible households that completed the survey, 842 children between six months and 12 years of age lived in an area impacted by refinery emissions. Ambient SO(2) exposure levels were estimated using dispersion modelling. Log-binomial regression models were used to estimate crude and adjusted prevalence ratios (PRs) and 95% CIs for the association between yearly school and residential SO(2) exposure estimates and asthma outcomes. Adjustments were made for child's age, sex, parental history of atopy and tobacco smoke exposure at home.
The adjusted PR for the association between active asthma and SO(2) levels was 1.14 (95% CI 0.94 to 1.39) per interquartile range increase in modelled annual SO(2). The effect on poor asthma control was greater (PR=1.39 per interquartile range increase in modelled SO(2) [95% CI 1.00 to 1.94]).
Results of the present study suggest a relationship between exposure to refinery stack emissions of SO(2) and the prevalence of active and poor asthma control in children who live and attend school in proximity to refineries.
The Health and Social Survey of Quebec Children and Youth, conducted on representative samples of children nine, 13 and 16 years of age, provided data on the prevalence and determinants of asthma and allergic rhinitis in Quebec.
To determine the prevalence of asthma and allergic rhinitis among children in the province of Quebec and to identify the determinants of these pathologies.
Three groups of more than 1100 children aged nine, 13 and 16 years were recruited. Respiratory symptoms were documented using the International Study of Asthma and Allergies in Childhood questionnaire. Questions enquiring about family income, smoking, degree of urbanization of the child's school's location and various variables related to indoor air were also included. The comparisons of proportions were done using the chi2 test.
The prevalence rates for reported history of asthma varied from 14% to 15% depending on the age group. The prevalence of wheezing in the past year was 7% to 8%. Asthma was the primary cause of the limitation of activities due to a health problem in nine- and 13-year-old Quebecers, and the second most common cause in 16-year-old Quebecers. The prevalence of rhinitis, rhinoconjunctivitis and reported history of hay fever increased with age, reaching 28.0%, 15.9% and 21.1%, respectively, in the 16-year-old group. The prevalence of asthma and wheezing was associated with family history and allergies, and inversely related to family income.
The prevalence of childhood asthma is high in the province of Quebec. It is a major cause of the limitation of activities due to a health problem for young Quebecers. A family history of asthma and an atopic predisposition are important determinants in the development of asthma in Quebec.
To share four Canadian cities' experiences with bed bug infestations and to explore public health roles in managing them.
We summarize presentations from a workshop at the 2010 Canadian Public Health Association Conference which examined the re-emergence of bed bugs in Canada and compared management approaches of municipal and public health authorities in four large Canadian cities. We include updates on their activities since the workshop.
Cities across Canada have observed an increase in complaints of bed bug infestations over recent years. Toronto Public Health considers bed bugs to be a threat to health and has been heavily involved in the front-line response to bed bug complaints. In Winnipeg, Montreal and Vancouver, city inspectors are responsible for investigating complaints, and public health plays a supporting or secondary role. We identified factors that may contribute to successful management of bed bugs: sufficient funding, partnerships among many stakeholders, training and education, and surveillance and evaluation.
Various public health agencies in Canadian cities have played key roles in the fight against bed bugs through new initiatives, education, and encouragement and support for others. By working with the public, owners, tenants, the health sector and other stakeholders, public health practitioners can begin to curb the resurgence of bed bugs and the social strains associated with them.
The absence of ongoing surveillance for childhood asthma in Montreal, Quebec, prompted the present investigation to assess the validity and practicality of administrative databases as a foundation for surveillance.
To explore the consistency between cases of asthma identified through physician billings compared with hospital discharge summaries.
Rates of service use for asthma in 1998 among Montreal children aged one, four and eight years were estimated. Correspondence between the two databases (physician billing claims versus medical billing claims) were explored during three different time periods: the first day of hospitalization, during the entire hospital stay, and during the hospital stay plus a one-day margin before admission and after discharge ('hospital stay +/- 1 day').
During 1998, 7.6% of Montreal children consulted a physician for asthma at least once and 0.6% were hospitalized with a principal diagnosis of asthma. There were no contemporaneous physician billings for asthma 'in hospital' during hospital stay +/- 1 day for 22% of hospitalizations in which asthma was the primary diagnosis recorded at discharge. Conversely, among children with a physician billing for asthma 'in hospital', 66% were found to have a contemporaneous in-hospital record of a stay for 'asthma'.
Both databases of hospital and medical billing claims are useful for estimating rates of hospitalization for asthma in children. The potential for diagnostic imprecision is of concern, especially if capturing the exact number of uses is more important than establishing patterns of use.
Cites: Annu Rev Public Health. 2001;22:213-3011274519
Cites: Can J Public Health. 2001 May-Jun;92(3):228-3211496637
Little information is available concerning the level of consumption and degree of contaminant exposure for North American women of childbearing age who eat sport fish. The authors reanalyzed a 1995-1996 study of Montreal-area (Canada) sport fishers. The authors focused on women sport fishers of childbearing age and male sport fishers who had spouses of childbearing age. The primary research involved an on-site questionnaire about fish consumption, with follow-up assessment of sport fishers estimated to have either the highest or lowest levels of fish-based contaminant exposure. Among the 1,654 interviewees were 100 women less than 45 yr of age who had eaten sport fish for an average of 11 yr; 45% ate fish less than once a month. From the follow-up subsample of high- and low-level consumers, the authors identified 17 women less than 45 yr of age and 25 males whose spouses who were less than 45 yr of age and who consumed similar quantities of sport fish. Among this group of 42, the high-exposure women differed from the low-exposure women with respect to their yearly consumption of freshwater fish, blood mercury levels (median = 6.4 vs. 1.4 microgram/l), and plasma polychlorinated biphenyl congener 99 (median = 10.5 vs. 5.9 microgram/kg plasma lipids). Few Montreal-area women of childbearing age consume local sport fish frequently or for extended periods. However, among the small proportion that consumes sport fish frequently or for extended periods, blood mercury concentrations approach levels of concern for fetal protection.
Extreme ambient heat is a serious public health threat, especially for the elderly and persons with pre-existing health conditions. Although much of the excess mortality and morbidity associated with extreme heat is preventable, the adoption of effective preventive strategies is limited. The study reported here tested the predictive power of selected components of the Health Belief Model for air-conditioning (AC) use among 238 non-institutionalized middle-aged and older adults with chronic heart failure and/or chronic obstructive pulmonary disease living in Montréal, Canada. Respondents were recruited through clinics (response rate 71%) and interviews were conducted in their homes or by telephone. Results showed that 73% of participants reported having a home air conditioner. The average number of hours spent per 24-hour period in air-conditioned spaces during heat waves was 14.5 hours (SD = 9.4). Exploratory structural equation modeling showed that specific beliefs about the benefits of and drawbacks to AC as well as internal cues to action were predictive of its level of use, whereas the perceived severity of the effects of heat on health was not. The findings are discussed in light of the need to adequately support effective response to extreme heat in this vulnerable population.
Unprecedentedly hot weather during the summer of 2009 resulted in considerable excess mortality in Greater Vancouver, Canada. Local municipalities and public health authorities requested a rapid, evidence-based recommendation for the temperature above which emergency action plans should be triggered to reduce potentially-avoidable mortality during future events.
Candidate trigger temperatures were identified by examining the coincidence of extreme mortality days with extreme temperature days, using temperatures observed at two regional airports. Days when the two coincided between 2005 and 2009 were defined as historical heat health emergencies. Forecast and observed temperatures were combined in multiple early warning scenarios to retrospectively test the capacity to predict those heat health emergency dates, and results were expressed in terms of true positive (emergency predicted when one occurred) and false positive (emergency predicted when one did not occur) triggers.
Extreme mortality was observed when the 2-day average of maximum temperatures was > or =31 degrees C at the coastal airport and > or =36 degrees C at the inland airport. When observed and forecast temperatures were combined in different early warning scenarios, all historical heat health emergencies were correctly identified in four of twelve cases, with a minimum of two false positive triggers.
A heat health emergency should be triggered for Greater Vancouver when the average of the current day's 14:00 observed temperature and the next day's forecast high is > or =29 degrees C on the coast and/or > or =34 degrees C inland. This condition provided 19 hours of lead time for preparation and was clearly understood by emergency responders and other users.
Temperature-mortality analyses are challenging in rural and remote communities with small populations, but this information is needed for climate change and emergency planning. The geographic health areas of British Columbia, Canada were aggregated into four ecoregions delineated by microclimatic conditions. Time series models were used to estimate the effect of maximum apparent temperature on daily non-traumatic mortality. The population of the coldest ecoregion was most sensitive to hot weather, while the population of the hottest ecoregion was least sensitive. The effects were consistently strongest in decedents aged less than 75 years. A province-wide total of 815 deaths was attributed to hot weather over the 25-year study period, with 735 deaths in the most populous ecoregion. The framework described could be adapted to other climatically variable regions with urban, rural, and remote populations.
*Environmental Health Services, British Columbia Centre for Disease Control, 655 West 12th Avenue, Vancouver, BC V5Z 4R4, Canada; †School of Population and Public Health, The University of British Columbia, 2206 East Mall, Vancouver, BC V5T 1Z3, Canada.
Residential exposure to radon gas is associated with increased risk of lung cancer, especially in smokers. Most evidence about the health effects of radon has been derived from meta-analyses on global epidemiologic studies, but administrative data can help public health authorities to explore the local impacts. Eighty health units in British Columbia (BC), Canada, were classified as having low, moderate, or high radon risk using more than 3,800 residential measurements. Vital statistics records were used to identify deaths due to lung cancer and to all natural causes. The annual ratio of lung cancer mortality to all natural mortality was plotted for the 1986-2012 study period for each radon classification. Visualizations were stratified by gender and by smoking prevalence. The overall ratio increased throughout the study period in high radon areas and remained stable in low and moderate radon areas. The increase was most pronounced for females, especially when plots were stratified by smoking prevalence. These limited but interesting findings confirm that radon is one risk factor for lung cancer mortality in BC and that its effects differ across gender and smoking strata. The results would be strengthened by replication, and more rigorous methods are required to assess other contributing factors.