The association between neighbourhood walkability and blood lipids: a Canadian population study.

We examined the association between walkability and blood lipids in a nationally representative sample of 29,649 participants aged 3-79 years who participated in the Canadian Health Measures Survey (CHMS) cycles 1 to 6. We focused on seven lipid biomarkers: apolipoprotein A (Apo A), apolipoprotein B (Apo B), triglycerides (TG), high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL), total cholesterol (TC), and TC/HDL. Cross-sectional associations were analyzed using generalized linear mixed models incorporating survey-specific sampling weights. An increase in the Canadian Active Living Environments Index, a measure of neighborhood walkability, equivalent to the magnitude of its interquartile range (IQR) was associated with the following percentage (95% confidence intervals (CI)) changes in lipids: decreased TG, -2.85 (-4.77, -0.93) and TC/HDL, -1.68 (-2.80, -0.56), and increased HDL, 1.68 (0.93, 2.42). Significant effects were largely restricted to adults (aged 17 to 79). In the younger age group there were no significant associations between walkability and lipids in the fully adjusted model. Significant associations were more frequently seen in females than males. For females, fully adjusted significant inverse associations were observed for TG, LDL, and TC/HDL, and there were positive associations with HDL and Apo A. Canadians living in more walkable neighborhoods have more favorable lipid profiles, suggesting that the built environment has the potential to influence the risk profile for cardiovascular health, especially among adults and females.

Cumulative Health Risk from Exposure Load (CHREL): Looking at multi-chemical exposures through the lens of biomonitoring guidance values.

Exposure load (EL) is an indicator of multiple chemical exposures based on human biomonitoring data. We used EL methodology and human biomonitoring health-based guidance values (HB2GVs) as exposure thresholds to create a new metric called Cumulative Health Risk from Exposure Load (CHREL). HB2GVs are derived by calculating the concentration of a biomarker consistent with a health protective exposure guidance value. CHREL analysis was conducted using Canadian Health Measures Survey (CHMS) cycle 3 and 4 biomonitoring data. Based on 18 chemicals, more than half of the Canadian population had an estimated CHRELTOTAL of 1 or more, indicative of chemical exposures potentially above selected exposure guidance values. Females had a significantly lower CHRELTOTAL compared to males, 12-19 year olds had a lower CHRELTOTAL compared to older age groups (significant compared to 40-59 year olds), and nonsmokers had a significantly lower CHRELTOTAL than smokers. Small segments of the population had a CHRELLIVER or a CHRELNERV of 1 or more, indicating exposures potentially above guideline levels for chemicals affecting the liver or nervous system. CHRELCANC was calculated based on 6 chemicals with HB2GVs derived for cancer endpoints. At the 10-5 risk level, most people had an estimated CHRELCANC of 3, indicative of multiple chemicals that may exceed negligible cancer risk. The most important contributors to exposures above HB2GVs were inorganic arsenic, mercury, acrylamide, xylenes, benzene and triclosan. Keeping certain assumptions, uncertainties and limitations in mind, the CHREL indicator can be used to obtain a picture of potential cumulative health risks from combined chemical exposures in a population, and as a comparative measure between subpopulations, including vulnerable subgroups.

Analysis of chemical exposures in racial populations in Canada: An investigation based on the Canadian health measures survey.

Despite demonstrated disparities in environmental chemical exposures by racial identity, no Canadian study has systematically assessed the feasibility of using a nationally representative dataset to examine differences in chemical concentrations by race. We assessed the feasibility and constraints of analysing chemical exposures in racial populations, including visible minorities and populations of Indigenous identity, using biomonitoring data collected through the Canadian Health Measures Survey (CHMS). Our primary objectives were to assess the ability to 1) generate geometric means and percentiles of chemical concentrations for racial populations by age or sex, 2) statistically compare concentrations among racial populations, and 3) calculate time trends of concentrations by race. We conducted these analyses for several priority chemicals: lead, cadmium, benzene, bisphenol A (BPA), and di(2-ethylhexyl) phthalate (DEHP). Survey participants self-identified as one of the following: White, Black, East and Southeast Asian, South Asian, Middle Eastern, Latin American, First Nations, Metis, and Inuit. Analyses were conducted for individual and combined cycles of the CHMS. Using data from the latest CHMS cycle in which each chemical was measured, we observed that sample sizes were sufficient to report geometric mean concentrations for all races except Inuit. Due to privacy considerations associated with small sample sizes, the 5th and 95th percentile concentrations could not be consistently reported for all racial populations in this analysis. While we were able to statistically compare concentrations among racial populations, the analysis was constrained by the limited number of statistical degrees of freedom available in a single CHMS cycle. Both of these constraints were alleviated by combining multiple cycles of data. The analysis of time trends was less subject to privacy and statistical limitations; we were able to calculate time trends of chemical concentrations for all racial populations. Our findings provide an important baseline for follow-up investigations of descriptive and etiological analyses of environmental chemical exposures and race in the CHMS.

Harmonizing the assessment of allostatic load across cycles of the Canadian Health Measures Survey: Variable selection and calculation method.

Background: The availability of measures to operationalize allostatic load - the cumulative toll on the body of responding to stressor demands - in population health surveys may differ across years or surveys, hampering analyses on the entire sampled population. Here, impacts of variable selection and calculation method were evaluated to generate an allostatic load index applicable across all cycles of the Canadian Health Measures Survey (CHMS). Methods: Data from CHMS cycles 1 to 4 were used to compare allostatic load scores when replacing the most prevalent risk factor, waist-to-hip ratio - available in cycles 1 to 4 but not 5 and 6 - with body mass index (BMI), waist circumference, waist circumference within BMI groups (classified as normal, overweight, or obese), or waist-to-height ratio. Indexes were generated using clinical or sex-specific empirically defined risk thresholds and as count-based or continuous scores. Logistic regression models that included age and sex were used to relate each potential index to socioeconomic indicators (educational attainment, household income). Results: Of the variables assessed, waist-to-height ratio and waist circumference were closest to waist-to-hip ratio according to an individual's percentile ranking and in classifying "at risk" using either clinical or empirically defined cut-offs. Allostatic load profiles generated using waist-to-height ratios most closely resembled profiles constructed using waist-to-hip ratios. Sex-dependent associations with educational attainment and household income were maintained across constructs whether indexes were count-based or continuous. Interpretation: Allostatic load profiles and associations with socioeconomic indicators were robust to variable substitution and method of calculation, supporting the use of a harmonized index across survey cycles to assess the cumulative toll on health of stressor exposure.

Proportions of trans fatty acids in erythrocytes of Canadian adults before the prohibition of partially hydrogenated oils in foods: results from the Canadian Health Measures Survey 2012-2015.

BACKGROUND: The partially hydrogenated oil (PHO) prohibition came into effect in Canada in September 2018 to reduce the intakes of total trans fatty acids (t-TFAs) and industrially produced TFAs (i-TFAs). OBJECTIVES: We aimed to estimate the red blood cell (RBC) proportions of t-TFA (primary objective) and total 18:1 TFA (secondary objective) of adults in Canada before the PHO prohibition and to identify the population subgroups at risk of higher TFA intakes. METHODS: We pooled data from 4025 adult participants of the cross-sectional Canadian Health Measures Survey cycles 3 and 4 (2012-2015). We estimated mean proportions, relative to total fatty acids (FAs), of RBC t-TFA and 18:1 TFA and their associations with sociodemographic, health, and lifestyle characteristics using multiple linear regression models. RESULTS: The nonadjusted mean RBC proportions of t-TFA and total 18:1 TFA were 0.59% (95% CI: 0.54, 0.63) and 0.27% (95% CI: 0.25, 0.29), respectively. In the adjusted models, the same participant characteristics were associated with t-TFA and 18:1 TFA but differences were generally smaller for 18:1 TFA than for t-TFA. Race, BMI, and alcohol intake were independently associated with RBC t-TFA and 18:1 TFA. Asian and Black participants had lower RBC t-TFA (-0.05% and -0.10% of total FA, respectively) than White participants. Obesity and high risk alcohol drinking were associated with slightly lower (≤0.06%) t-TFA proportions than lower adiposity and alcohol intake concentrations, respectively. CONCLUSIONS: Pre-PHO prohibition in food in Canada, t-TFA proportions were relatively low compared with a proposed threshold of 1% of total RBC FAs, over which cardiovascular disease risk may be higher. Previous voluntary initiatives to reduce i-TFA in the food supply may explain these relatively low RBC t-TFA concentrations. Some population subgroups had higher baseline RBC TFA than other subgroups, but the physiological implications of these small differences, at relatively low baseline RBC TFA proportions, remain to be determined.

Do blood metals influence lipid profiles? Findings of a cross-sectional population-based survey.

Dyslipidemia, an imbalance of lipids and a major risk factor for cardiovascular disease, has been associated with elevated blood and urine levels of several heavy metals. Using data from a Canadian Health Measures Survey (CHMS), we tested associations between blood levels of cadmium, copper, mercury, lead, manganese, molybdenum, nickel, selenium, and zinc, and the lipids triglycerides (TG), total cholesterol (TC), low density lipoproteins (LDL), high density lipoproteins (HDL) and apolipoproteins A1 (APO A1), and B (APO B). All adjusted associations between single metals and lipids were positive and significant, except for APO A1 and HDL. The joint effect of an interquartile range increase in heavy metals was positively associated with percentage increases of TC, LDL and APO B of 8.82% (95%CI: 7.06, 10.57), 7.01% (95%CI: 2.51, 11.51) and 7.15% (95%CI: 0.51, 13.78), respectively. Future studies are warranted to determine if reducing environmental exposure to heavy metals favorably influences lipid profiles and the risk of cardiovascular disease.

Achievement of the ABC goal among Canadians with type 2 diabetes and the influence of physical activity: data from the Canadian Health Measures Survey.

Achieving the three therapeutics targets known as ABC (A1c ≤ 7.0%, LDL-C < 2.0 mmol/L, and resting BP < 130/80 mmHg), limiting sedentary behaviors as well as accumulating a total of 150 min/week of moderate-to-vigorous aerobic exercise reduce the risk of cardiovascular disease in type 2 diabetes (T2D) individuals. However, more recent data regarding the achievement of ABC over time in Canada is needed and it remains to be determined how sedentary behaviors and physical activity levels can influence its achievement. Analyses were performed using a total of 17 582 individuals (18-79 years) from the 2007-2017 Canadian Health Measures Survey. Sedentary behaviors and physical activity levels were estimated using an accelerometer for a total of 7 consecutive days and quartiles of physical activity were used to categorize individuals. The prevalence of T2D has increased from 2007 to 2017 in the Canadian population (from 4.80% to 8.38%) with a considerable number of undiagnosed patients. The achievement of ABC went from 11.53% [11.49%-11.57%] in 2007 to 14.84% [14.80%-14.89%] in 2017 in T2D individuals. Moderate-to-vigorous physical activity (MVPA) levels were positively but weakly correlated to the achievement of the ABC (r = 0.044; p = 0.001), while sedentary time and light physical activity were not (r < -0.014; p = 0.266). Only 8.8% of individuals with the lowest level of MVPA (Q1) reached the ABC while 15.1% of the most active individuals (Q4) reached the triple target. In addition to physical activity, other important factors such as body mass index and medication use should also be considered as modifiable contributing factors.

Iron Status and Associated Factors among Canadian Women: Results from the Canadian Health Measures Survey.

BACKGROUND: Iron deficiency and overload may negatively impact women's health. There has been limited assessment of iron status and its associated factors among Canadian women. OBJECTIVES: This study investigated associations of various sociodemographic, lifestyle, medication, and dietary factors with body iron stores among pre- and postmenopausal women in Canada. METHODS: Analyses were conducted using cross-sectional, nationally representative survey and biomarker data from women aged 20-79 y (n = 6362) in the Canadian Health Measures Survey (2009-2017). Body iron stores were assessed by measuring serum concentrations of ferritin (SF). Information on potential correlates was collected during an in-home interview. Multivariable linear regression analyses were performed to evaluate associations with SF concentration, and logistic regression was used to estimate associations with iron deficiency (SF <15 µg/L) or elevated iron stores (SF >150 µg/L). RESULTS: Geometric mean SF concentrations were significantly higher in postmenopausal than in premenopausal women (73.2 versus 33.8 µg/L; P < 0.001). The prevalence of iron deficiency among pre- and postmenopausal women was 16.0% and 4.0%, respectively, whereas that of elevated iron stores was 2.7% and 21.0%, respectively. After simultaneous adjustment for multiple factors, including high-sensitivity CRP (inflammation marker), we found that age, East/Southeast Asian (versus White) race/ethnicity, alcohol, and red meat consumption were positively associated with SF concentration among pre- and postmenopausal women. In addition, aspirin use and dairy consumption were inversely associated with SF concentration among postmenopausal women only. Similar patterns were observed for associations with elevated iron stores among postmenopausal women, whereas higher grain consumption was associated with an increased prevalence of iron deficiency among premenopausal women. CONCLUSIONS: Sociodemographic, lifestyle, medication, and dietary factors are correlated with iron status determined by SF concentration among Canadian women. The findings may have implications for intervention strategies aimed at optimizing body iron stores in pre- and postmenopausal women.

Health Utilities Index Mark 3 scores for children and youth: Population norms for Canada based on cycles 5 (2016 and 2017) and 6 (2018 and 2019) of the Canadian Health Measures Survey.

Background: Utility scores are an important tool for evaluating health-related quality of life. Utility score norms have been published for Canadian adults, but no nationally representative utility score norms are available for children and youth. Data and methods: Health Utilities Index Mark 3 (HUI3) data from two recent cycles of the Canadian Health Measures Survey (i.e., 2016 and 2017, and 2018 and 2019) were used to provide utility score norms for children aged 6 to 11 years and adolescents aged 12 to 17 years. Children younger than 14 years answered the HUI3 under the supervision of an adult, while older children answered without supervision. Utility scores were reported as a weighted average (95% confidence intervals [CIs]) and median values (interquartile range). Utility scores were stratified by sociodemographic and medical characteristics of the child or adolescent. Regression analyses were used to identify predictors of utility scores. All results were weighted using sampling weights provided by Statistics Canada. Results: Among the 2,297,136 children aged 6 to 11 years and the 2,329,185 adolescents aged 12 to 17 years in the weighted sample, the average utility scores were 0.95 (95% CI: 0.94 to 0.95) and 0.89 (95% CI: 0.87 to 0.90), respectively. Approximately 60% of the children and 34% of the adolescents had a utility score of 1.00. Analyses identified several factors associated with utility scores (e.g., age, chronic condition and income levels), although differences were observed between children and adolescents. Interpretation: This study provides utility score estimates based on a nationally representative sample of Canadian children and youth. Further research examining the determinants of utility scores of children and adolescents is warranted.

Sociodemographic and endogenous factors associated with access to eye care in Canada, 2016 to 2019.

Introduction: Eye care is important, but it is not always promoted as much as other aspects of health. A visit to an eye care professional is made when need, stimulus, access and availability exist. Data and methods: Data from cycles 5 and 6 (2016 to 2019) of the Canadian Health Measures Survey were used. Analyzed variables were related to sociodemographic characteristics, general health, behaviour and eye health. Estimates were obtained using survey weights, and 95% confidence intervals were obtained with bootstrap weights. Results: From 2016 to 2019, 75% of people diagnosed with diabetes visited an eye care professional during the previous year. For people not diagnosed with diabetes, the rate varied, at 57% for those aged 6 to 18 years, 40% for those aged 19 to 64, and 63% for those aged 65 to 79. For those aged 6 to 64, wearing glasses and having access to a family doctor were the main factors associated with a visit to an eye care professional in the previous year. For those aged 65 to 79, cataracts, sex, marital status and self-perceived quality of life were the most significant factors. Interpretation: Although wearing glasses or having eye diseases was associated with a visit to an eye care professional, this study revealed additional emerging associated factors: access to a family doctor for people aged 6 to 64, and an excellent or very good self-perceived quality of life for those aged 65 to 79.

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 association between blood PFAS concentrations and clinical biochemical measures of organ function and metabolism in participants of the Canadian Health Measures Survey (CHMS).

Per- and poly-fluoroalkyl substances (PFAS) are ubiquitous and may persist in human tissue for several years. Only a small proportion of PFAS have been studied for human health effects. We tested the association between human blood levels of six PFAS and several clinical measures of organ and metabolic function in a nationally representative sample of 6768 participants aged 3-79 years old who participated in the Canadian Health Measures Survey. Cross-sectional associations were assessed by generalized linear mixed models incorporating survey-specific sampling weights. An increase in perfluorooctanoic acid (PFOA) equivalent to the magnitude of its geometric mean (GM) of 2.0 µg/L was associated with percentage (95% CI) increases in serum enzymes reflecting liver function: aspartate aminotransferase (AST) 3.7 (1.1, 6.4), gamma-glutamyl transferase (GGT) 11.8 (2.5, 21.8), alanine aminotransferase (ALT) 3.2 (0.5, 5.9), and bilirubin 3.6 (2.7, 4.5). A GM increase in perfluorodecanoic acid (PFDA) of 0.2 µg/L was positively associated with percentage increases in GGT, triglycerides, low-density lipoprotein (LDL) cholesterol, total cholesterol, and calcium with respective increases of 15.5 (2.2, 30.4), 7.0 (1.0, 13.2), 10.7 (5.5, 16.1), 2.8 (0.2, 5.3), and 0.8 (0.3, 1.3). PFOA, perfluorooctane sulfonate (PFOS), PFDA and perfluorononanoic acid (PFNA) were positively associated with GGT. All six congeners were positively associated with at least one biomarker of lipid metabolism, and 5 of 6, PFOA, PFOS, PFDA, perfluorohexane sulfonate (PFHxS) and PFNA were positively associated with serum calcium. Exposure to selected PFAS is associated with clinical blood tests reflecting metabolism and the function of several organ systems. These relatively small changes may possibly indicate early pathology that is clinically inapparent and may possibly be of significance in a general population or in individuals exposed to very high levels of PFAS.

Hypertension associated with hearing health problems among Canadian adults aged 19 to 79 years.

BACKGROUND: Hypertension is a common condition experienced by close to one-quarter of the adult population in Canada. There is evidence that this condition or the medications used to treat it may lead to hearing health problems (defined in this study as having hearing loss, tinnitus or both conditions). DATA AND METHODS: Data from the Canadian Health Measures Survey from 2012 to 2015 were used to estimate the prevalence of hypertension and hearing health problems for individuals aged 19 to 79 years (n=6,198). Data from cycles 3 (n=3,072) and 4 (n=3,126) were combined. The relationship of hypertension to hearing health problems was assessed with multivariate logistic regression. RESULTS: An estimated 40% of the adult population were free of hearing health problems, while the remaining 60% had either hearing loss (23%), tinnitus (22%) or both conditions (14%); 22% of the adult population had hypertension. Hearing health problems were significantly more prevalent among adults with hypertension (79%) than among those without hypertension (54%). Hypertension was associated with greater odds of hearing health problems in both males (adjusted odds ratio [AOR]=1.7) and females (AOR=1.6), even after accounting for age, sociodemographic, health-related and noise exposure variables. INTERPRETATION: This study adds to the body of evidence that identifies hypertension as a potentially modifiable risk factor for hearing loss and tinnitus. Males and females with hypertension had a higher risk of experiencing hearing health problems, demonstrating the importance of screening those with hypertension for hearing health.

Urinary Fluoride Levels among Canadians with and without Community Water Fluoridation.

Drinking water is a major source of dietary fluoride intake in communities with water fluoridation. We examined the association between urinary fluoride adjusted for specific gravity (UFSG) and tap water fluoride levels, by age and sex, among individuals living in Canada. Participants included 1629 individuals aged 3 to 79 years from Cycle 3 (2012-2013) of the Canadian Health Measures Survey. We used multiple linear regression to estimate unique associations of tap water fluoride levels, age, sex, ethnicity, body mass index (BMI), use of fluoride-containing dental products, smoking in the home, and tea consumption with UFSG. UFSG concentration was significantly higher among participants who received fluoridated drinking water (mean = 1.06 mg/L, standard deviation = 0.83) than among those who did not (M = 0.58 mg/L, SD = 0.47), p < 0.01. UFSG increased over adulthood (ages 19 to 79). Higher UFSG concentration was associated with being female, tea drinking, and smoking in the home. In conclusion, community water fluoridation is a major source of contemporary fluoride exposure for Canadians. Lifestyle factors including tea consumption, as well as demographic variables such as age and sex, also predict urinary fluoride level, and are therefore important factors when interpreting population-based fluoride biomonitoring data.

Trends in environmental chemical concentrations in the Canadian population: Biomonitoring data from the Canadian Health Measures Survey 2007-2017.

Ten years of nationally representative biomonitoring data collected between 2007 and 2017 are available from the Canadian Health Measures Survey (CHMS). These data establish baseline environmental chemical concentrations in the general population. Here we sought to evaluate temporal trends in environmental chemical exposures in the Canadian population by quantifying changes in biomarker concentrations measured in the first five two-year cycles of the CHMS. We identified 39 chemicals that were measured in blood or urine in at least three cycles and had detection rates over 50% in the Canadian population. We calculated geometric mean concentrations for each cycle using the survey weights provided. We then conducted analyses of variance to test for linear trends over all cycles. We also calculated the percent difference in geometric means between the first and most recent cycle measured. Of the 39 chemicals examined, we found statistically significant trends across cycles for 21 chemicals. Trends were decreasing for 19 chemicals from diverse chemical groups, including metals and trace elements, phenols and parabens, organophosphate pesticides, per- and polyfluoroalkyl substances, and plasticizers. Significant reductions in chemical concentrations included di-2-ethylhexyl phthalate (DEHP; 75% decrease), perfluorooctane sulfate (PFOS; 61% decrease), perfluorooctanoic acid (PFOA; 58% decrease), dimethylphosphate (DMP; 40% decrease), lead (33% decrease), and bisphenol A (BPA; 32% decrease). Trends were increasing for two pyrethroid pesticide metabolites, including a 110% increase between 2007 and 2017 for 3-phenoxybenzoic acid (3-PBA). No significant trends were observed for the remaining 18 chemicals that included arsenic, mercury, fluoride, acrylamide, volatile organic compounds, and polycyclic aromatic hydrocarbons. National biomonitoring data indicate that concentrations, and therefore exposures, have decreased for many priority chemicals in the Canadian population. Concentrations for other chemical groups have not changed or have increased, although average concentrations remain below thresholds of concern derived from human exposure guidance values. Continued collection of national biomonitoring data is necessary to monitor trends in exposures over time.

Prescription medication use among Canadian children and youth, 2012 to 2017.

BACKGROUND: Prescription medications are used throughout the life course, including among children and youth. Prescribing practices may be influenced by emerging medical conditions, the availability of new medications, changing clinical practices, and evolving knowledge of the safety and effectiveness of medications. The Canadian Health Measures Survey (CHMS) provides national-level information to help monitor the use of prescribed medications in the population. DATA AND METHODS: Based on data from the CHMS (2012 to 2017), this article describes prescription medication use in the past month among those aged 3 to 19 years. Information on up to 45 prescription medications was recorded and classified according to Health Canada's Anatomical Therapeutic Chemical classification. Frequencies and bivariate analyses examined medication use by sociodemographic and health-related factors. The most common medication classes were identified for each age group. RESULTS: An estimated 23% of Canadian children and youth (1.5 million) had used at least one prescription medication in the past month and 9% had used two or more prescription medications.Prescription medication use was more common among those who reported lower levels of general and mental health, as well as among those with asthma (51%), a mood disorder (71%), attention deficit disorder (60%) or a learning disability (43%). Medications for the respiratory and nervous systems were among those most commonly prescribed. Of youth aged 14 years or older, 4% had misused prescription medications for non-medicinal purposes, for the experience, for the feeling they cause or to get high. DISCUSSION: Prescription medication use among children and youth is common in Canada. It is associated with lower levels of self-reported health and the presence of chronic conditions. The estimates provide a benchmark to help monitor prescription drug use in Canada.

Proportions of long-chain ω-3 fatty acids in erythrocyte membranes of Canadian adults: Results from the Canadian Health Measures Survey 2012-2015.

BACKGROUND: The Omega-3 Index (OI) is a proposed marker of coronary artery disease (CAD) risk. Another index, the EPA/arachidonic acid (AA) ratio has also been proposed as a possible risk marker for CAD. OBJECTIVE: Our primary objective was to characterize the Canadian population subgroups that have an undesirable OI (<4%, associated with high CAD risk) and to identify the participants' characteristics most strongly associated with the OI. Our secondary objective was to identify the characteristics most strongly associated with the EPA/AA ratio. DESIGN: Data from 4025 adult participants of cycles 3 and 4 (2012-2015) of the cross-sectional Canadian Health Measures Survey were pooled. Adjusted mean proportions of erythrocyte membrane ω-3 (n-3) fatty acids, total ω-6 fatty acids, and ratios were analyzed by sociodemographic, health, and lifestyle characteristics using covariate-adjusted models. RESULTS: The mean OI was 4.5%. Almost 40% of Canadians had an undesirable (<4%) OI. ω-3 supplement use, fish intake, and race were the variables most strongly associated with OI scores. The prevalence of undesirable OI was significantly higher among participants consuming fish less than twice a week (43.8%; 95% CI: 39.0%, 48.6%) than among those consuming more fish (12.7%; 95% CI: 7.8%, 19.9%), among smokers (62.7%; 95% CI: 52.9%, 71.7%) than nonsmokers (33.4%; 95% CI: 29.4%, 37.7%), in whites (42.7%; 95% CI: 38.2%, 47.4%) than in Asians (23.0%; 95% CI: 15.4%, 33.0%), and in adults aged 20-39 y (49.6%; 95% CI: 42.3%, 56.9%) than in those aged 60-79 y (24.4%; 95% CI: 21.0%, 28.1%). ω-3 supplement intake and fish intake were the characteristics most strongly associated with EPA/AA. All P ≤ 0.05. CONCLUSIONS: An important proportion of Canadian adults has an undesirable (<4%) OI, with higher prevalence in some subgroups. Further assessment is required to determine the value and feasibility of an increase in the population's OI to the currently proposed target of ≥8% as a potential public health objective.

Exposure to tobacco smoke among Canadian nonsmokers based on questionnaire and biomonitoring data.

BACKGROUND: Secondhand smoke exposure (SHSe) is associated with numerous adverse health effects and is a major burden for those who do not smoke. SHSe has been primarily characterized via questionnaire, but exposure levels can also be estimated using a specific biomarker, such as cotinine (COT). DATA AND METHODS: Urinary COT measurements and questionnaire data from three cycles (2007 to 2013) of the Canadian Health Measures Survey were combined and analyzed as indicators of regular SHSe for nonsmokers aged 6 to 79 years. Exposure extent was examined by demographic and socioeconomic variable, dwelling type, and exposure location. RESULTS: Among Canadian nonsmokers, 22% reported having been regularly exposed to smoke; of those, 26% had detectable COT. The range of SHSe significantly differed by age group and exposure location. While the most frequently reported location category was "outside their home" (16%), the most important contributor to elevated COT was exposure "at home". The creatinine-adjusted COT geometric mean (C_COT-GM) for the nonsmokers aged 6 to 79 reporting regular home exposure was 3.7 µg/g, but the C_COT-GM was almost three times higher for those living in an apartment than for those in a single-detached home. Some discrepancy appeared between self-reported SHSe and detectable COT estimates for the assessed subpopulations. DISCUSSION: Surveillance by questionnaire and biomonitoring both have their own advantages and are fundamental in identifying the subpopulations most susceptible to SHSe. Using a biomarker provides a quantitative estimate of relative exposure that can be compared over time and with other studies, and this is of particular interest for effective public health interventions.

Opportunities and Challenges From Leading Trends in a Biomonitoring Project: Canadian Health Measures Survey 2007-2017.

Background: Biomonitoring can be conducted by assessing the levels of chemicals in human bodies and their surroundings, for example, as was done in the Canadian Health Measures Survey (CHMS). This study aims to report the leading increasing or decreasing biomarker trends and determine their significance. Methods: We implemented a trend analysis for all variables from CHMS biomonitoring data cycles 1-5 conducted between 2007 and 2017. The associations between time and obesity were determined with linear regressions using the CHMS cycles and body mass index (BMI) as predictors. Results: There were 997 unique biomarkers identified and 86 biomarkers with significant trends across cycles. Nine of the 10 leading biomarkers with the largest decreases were environmental chemicals. The levels of 1,2,3-trimethyl benzene, dodecane, palmitoleic acid, and o-xylene decreased by more than 60%. All of the 10 chemicals with the largest increases were environmental chemicals, and the levels of 1,2,4-trimethylbenzene, nonanal, and 4-methyl-2-pentanone increased by more than 200%. None of the 20 biomarkers with the largest increases or decreases between cycles were associated with BMI. Conclusions: The CHMS provides the opportunity for researchers to determine associations between biomarkers and time or BMI. However, the unknown causes of trends with large magnitudes of increase or decrease and their unclear impact on Canadians' health present challenges. We recommend that the CHMS plan future cycles on leading trends and measure chemicals with both human and environmental samples.

Regional variations in human chemical exposures in Canada: A case study using biomonitoring data from the Canadian Health Measures Survey for the provinces of Quebec and Ontario.

The Canadian Health Measures Survey (CHMS), an ongoing national health survey conducted in two-year cycles, collects extensive biomonitoring data that is used to assess the exposure of Canadians to environmental chemicals of concern. Combining data from multiple cycles of the CHMS allows for the calculation of robust regional estimates of chemical concentrations in blood and urine. The objective of this work was to compare biomarkers of exposure to several environmental chemicals for the provinces of Quebec and Ontario, two major CHMS regions, as well as the entire CHMS (representing Canada) minus Quebec (CMQ), and the entire CHMS minus Ontario (CMO), and to interpret differences between regions. Geometric means and 95th percentiles of blood and/or urinary concentrations of 45 environmental chemicals or their metabolites for Ontario, Quebec, CMQ, and CMO were calculated by combining the two most recent cycles of data available for a chemical (cycles 1 and 2, or cycles 2 and 3) from the first three cycles of the CHMS (2007-2013). Weighted one-way ANOVA was used to test the differences between regional estimates. After applying a Bonferonni-Holm adjustment for multiple comparisons, the following measures were significantly higher in Quebec as compared to Ontario and CMQ: blood lead, urinary lead and the urinary polyaromatic hydrocarbon (PAH) metabolites, 9-hydroxyfluorene, 1-hydroxyphenanthrene, 2- hydroxyphenanthrene and 3-hydroxyphenanthrene. In Quebec compared to CMQ only, urinary 2-hydroxfluorene, 3-hydroxyfluorene, 2-hydroxynaphthalene, and 4-hydroxyphenanthrene were higher. The concentration of urinary fluoride was significantly higher in Ontario as compared to Quebec and CMO. Blood manganese and urinary fluoride were significantly lower in Quebec compared to CMQ, and blood and urinary selenium were significantly lower in Ontario compared to CMO. Regional differences in tobacco use, age of dwellings and drinking water fluoridation are among the possible contributing factors to some of the observed differences. In conclusion, this is the first study where biomonitoring data from multiple cycles of CHMS were combined in order to generate robust estimates for subsets of the Canadian population. Such assessments can contribute to a regional-level prioritization of control measures to reduce the exposure of Canadians to chemicals in their environment.