Airflow obstruction in young adults in Canada.

OBJECTIVE: Airflow obstruction is relatively uncommon in young adults, and may indicate potential for the development of progressive disease. The objective of the present study was to enumerate and characterize airflow obstruction in a random sample of Canadians aged 20 to 44 years. SETTING: The sample (n=2962) was drawn from six Canadian sites. DESIGN: A prevalence study using the European Community Respiratory Health Survey protocol was conducted. Airflow obstruction was assessed by spirometry. Bronchial responsiveness, skin reactivity to allergens and total serum immunoglobulin E were also measured. Logistic regression was used for analysis. RESULTS: Airflow obstruction was observed in 6.4% of the sample, not associated with sex or age. The risk of airflow obstruction increased in patients who had smoked and in patients who had lung trouble during childhood. Adjusted for smoking, the risk of airflow obstruction was elevated for subjects with past and current asthma, skin reactivity to allergens, elevated levels of total immunoglobulin E and bronchial hyper-responsiveness. Of the subjects with airflow obstruction, 21% were smokers with a history of asthma, 50% were smokers without asthma, 12% were nonsmokers with asthma and 17% were nonsmokers with no history of asthma. Bronchial hyper-responsiveness increased the prevalence of airflow obstruction in each of these groups. CONCLUSION: Smoking and asthma, jointly and individually, are major determinants of obstructive disorders in young adults. Bronchial hyper-responsiveness contributes to obstruction in both groups.

Widespread micronutrient inadequacies among adults in prince edward island.

PURPOSE: The prevalence of micronutrient inadequacies was assessed among adult residents of Prince Edward Island (PEI) in the PEI Nutrition Survey. METHODS: A peer-reviewed protocol was used in this cross-sectional survey, in which 24-hour recalls were administered during in-home interviews. A stratified random sample of 1,995 adults aged 18 to 74 participated. Median nutrient intakes with and without supplements were calculated; intakes were adjusted for day-to-day variability. Chi-square testing was used to assess differences in prevalence of inadequacy by age and sex. RESULTS: Most of the sample (more than 90%) had folate intakes below the Estimated Average Requirement (EAR). Magnesium and vitamin C intakes were low in more than 50% of the sample. Iron intakes were adequate in all groups except women aged 19 to 50, 29% of whom had intakes below the EAR. Women were more likely than men to have inadequate intakes. Median calcium intakes fell below recommendations for all age and sex groups. Supplement use had little impact on dietary adequacy in this sample. CONCLUSIONS: This study underscores the need for public health interventions designed to reduce the very high prevalence of nutrient inadequacies in the PEI adult population. In addition, education is needed on the selection of appropriate vitamin and mineral supplements.

How soon after a prior tetanus-diphtheria vaccination can one give adult formulation tetanus-diphtheria-acellular pertussis vaccine?

BACKGROUND: Adult formulation tetanus and diphtheria toxoids and acellular pertussis vaccines (Tdap) have been developed to prevent pertussis in adolescents and adults. There are concerns that unacceptable rates of severe injection site reactions, including Arthus-type reactions might occur if Tdap is administered too soon after a previous tetanus and diphtheria toxoid-containing vaccine formulated for infants and younger children (TD) or older children and adults (Td). METHODS: To evaluate whether adverse reactions after Tdap might be related to time since last receipt of TD/Td, we performed an open label, province-wide, clinical trial comparing the reactogenicity of Tdap given 18 months-9 years versus > or = 10 years after a previous TD/Td. RESULTS: Seven thousand one hundred fifty-six children and adolescents were enrolled in the study (464-963 subjects per cohort), and 7001 had documented dates of the previous immunization within the specified intervals; adverse event data were provided by 5931 (84.7%). No whole limb swelling, Arthus-like reactions or serious adverse events related to vaccination were reported. No differences in reports of fever were found by interval since last immunization. Injection site erythema and swelling were slightly and statistically significantly increased among those participants with most recent prior TD/Td. Compared with the 10-year interval group, the maximum increase for any other group was < or = 8.6% for any erythema, < or = 6% for erythema > 10 mm, < or = 10.3% for any swelling, < or = 6.9% for swelling > 10 mm, < or = 5.2% for any pain and < or = 3.7% for moderate/severe pain. CONCLUSION: Although there is a slight increase in injection site events with decreasing interval since a previous immunization, Tdap can be safely administered at intervals of > or = 18 months since a previous TD/Td vaccine.

Geographic and gender variability in the prevalence of bronchial responsiveness in Canada.

OBJECTIVES: Geographic variability in reported prevalences of asthma worldwide could in part relate to interpretation of symptoms and diagnostic biases. Bronchial responsiveness measurements provide objective evidence of a common physiologic characteristic of asthma. We measured bronchial responsiveness using the standardized protocol of the European Community Respiratory Health Survey (ECRHS) in six sites in Canada, and compared prevalences across Canada with international sites. DESIGN: Samples of 3,000 to 4,000 adults aged 20 to 44 years were randomly selected in Vancouver, Winnipeg, Hamilton, Montreal, Halifax, and Prince Edward Island, and a mail questionnaire was completed by 18,616 individuals (86.5%). Preselected random subsamples (n = 2,962) attended a research laboratory for examination including more detailed questionnaires, lung function testing including methacholine challenge, and skin testing with 14 allergens. RESULTS: Prevalences of bronchial hyperresponsiveness, measured as cumulative dose of methacholine required to produce a 20% fall from the post-saline solution FEV1 < or = 1 mg, ranged from 4.9% (95% confidence interval [CI], 1.6 to 8.5) in Halifax to 22.0% (95% CI, 18.1 to 26.0) in Hamilton (median, 10.7%). In all Canadian sites, bronchial hyperresponsiveness was more prevalent in women than in men. Neither the geographic nor gender differences were accounted for by differences in age, smoking, skin test reactivity, or baseline FEV1. Geographic- and gender-related variability changed little when only bronchial hyperresponsiveness associated with asthma-like symptoms was considered. CONCLUSIONS: A wide variability in bronchial responsiveness can occur within one country, almost as wide as the range found across all international sites participating in the ECRHS study and not explained by differences in gender, smoking, skin test reactivity, and FEV1. While gender variability in the prevalence of bronchial responsiveness is likely due to hormonal and immunologic factors, geographic variability is likely to result from environmental factors.

Measured weights in PEI adults reveal higher than expected obesity rates.

BACKGROUND: The increasing prevalence of obesity and overweight in Canada is a significant health concern. Unfortunately, we know very little about the actual weight status and associated health risks in our population since most surveys use only self-reported body weights and heights and typically do not include a measure of body fat distribution. This paper summarizes the findings of the Prince Edward Island Nutrition Survey. METHODS: A random sample of 1,995 adults aged 18-74 were interviewed in their homes and weights, heights and waist circumference measurements were obtained. Relative health risks, population proportions and their corresponding 95% confidence intervals were calculated. RESULTS: Overall, almost one third of PEI adults are obese (BMI > or = 30). This is almost double that reported in the 1995 National Population Health Survey using self-reported heights and weights. More women were classified as being very severely obese (Class III) than men, but for both men and women there appears to be a trend of increased mild obesity with age. Based on BMI and waist circumference, over one third of the population is considered to be at high to extremely high risk for health problems. CONCLUSION: Self-reported height and weight data appear to result in significant underestimation of the problem of obesity. Given the serious health consequences associated with this condition, it is critical that measured heights and weights be collected in future population-based surveys to ensure that public health interventions are based on accurate prevalence data.

Canada's first universal varicella immunization program: Lessons from Prince Edward Island.

A live attenuated varicella vaccine was licensed in Canada in December 1998. The first universal varicella immunization program in Canada was initiated in Prince Edward Island in 2000. Students in grades one to six without a history of varicella were offered the vaccine, administered by Public Health Nurses, in school clinics during February and March 2000. The acceptance rate ranged from 29.1% of all grade one students to 9.8% of all grade six students; overall, 18.8% of students received the vaccine. A universal program for children 12 months of age was introduced on April 1, 2000 and catch-up clinics for those between 12 months of age and those in grade one were introduced in June 2000. Repeated media announcements and the cooperation of staff in schools and daycare facilities assisted in informing parents about the availability of the vaccine. Vaccine-associated adverse events have been uncommon and the vaccine has been well accepted.

Canadian hepatitis C look-back investigation to detect transmission from an infected general surgeon.

BACKGROUND: In February 2007, a general surgeon in Charlottetown, Prince Edward Island, tested positive for hepatitis C virus (HCV). The surgeon's infection onset date could not be determined; however, episodic hepatic enzyme elevations were first detected in November 2004 and again in February 2007. HCV transmission during surgery, alhough rare, has been documented. A phased look-back HCV screening program was conducted to detect HCV transmission from this surgeon to patients who underwent the highest-risk procedures in the three years before his positive test. METHODS: Highest-risk procedures were defined as exposure-prone procedures (EPP) in which exposure to the surgeon's blood was most likely. EPP patients from January 2004 to February 2007 were identified using hospital and administrative records. Linkages with the provincial notifiable disease for HCV was performed, and death records for deceased EPP patients were reviewed. Eligible patients were invited for screening. RESULTS: Of 6248 patients seen in phase 1, 272 (4.4%) were identified to be EPP. Of the 272 patients, 248 (91.1%) were invited for HCV testing and 24 (8.8%) were deceased. To date, 231 of 248 (93.1%) patients have presented for screening. Two patients (one alive, one deceased) were HCV positive before their EPP. Viral sequence of the surgeon's isolate is unrelated to the first patient; the second individual has a resolved infection (polymerase chain reaction negative). No new transmission events were identified in the screened patients. The 95% CI of the transmission probability was estimated to be 0 to 0.016. INTERPRETATION: HCV transmission from the surgeon during a 38-month look back was unlikely. In the absence of protocols for investigating HCV transmission from infected health care workers, screening was initially prioritized to the highest-risk patients. The investigation has been satisfactorily terminated based on these results.