Opioid and Cannabis Use During Pregnancy and Breastfeeding in Relation to Sociodemographics and Mental Health Status: A Descriptive Study.

OBJECTIVE: This study of Canadian women estimates the prevalence of opioid and cannabis use during pregnancy and cannabis use during the breastfeeding period and explores the sociodemographic and mental health characteristics associated with use. METHODS: A total of 13 000 women who gave birth between January and June 2018 were invited to participate in the Survey on Maternal Health by Statistics Canada; 7111 women participated for a response rate of 54.7%. Participants were asked about their mental health, supports during pregnancy, and substance use. Multivariable logistic regression was used to describe the relationship between sociodemographic and mental health characteristics and substance use during pregnancy and while breastfeeding. RESULTS: The prevalence of self-reported opioid use during pregnancy was 1.4% (95% confidence interval [CI] 1.1%-1.8%). A higher proportion of women reported using cannabis during pregnancy and while breastfeeding, at 3.1% (95% CI 2.5%-3.6%) and 2.6% (95% CI 2.1%-3.1%), respectively. Younger age, not being in a relationship, lower level of education, and thoughts of self-harm were significantly associated with cannabis use during pregnancy. Lower level of education and thoughts of self-harm were also significantly associated with cannabis use while breastfeeding, as were symptoms of postpartum depression and/or generalized anxiety. Lower level of education and symptoms of postpartum depression and/or generalized anxiety were also significantly associated with opioid use during pregnancy. CONCLUSION: The results of this survey show relatively low levels of opioid and cannabis use during pregnancy and cannabis use while breastfeeding in Canada. Different sociodemographic and mental health characteristics are associated with the use of these substances, and public health interventions and policies should take into account these factors.

Prevalence of Positive Mental Health and Associated Factors Among Postpartum Women in Canada: Findings from a National Cross-Sectional Survey.

OBJECTIVES: The objectives of this study were to compare the prevalence of three positive mental health (PMH) outcomes (self-rated mental health, life satisfaction, sense of community belonging) in postpartum women to the general population, and to examine the relationship between protective factors and the three PMH outcomes among postpartum women. METHODS: The national cross-sectional Survey on Maternal Health (n = 6558) was analyzed. Analyses were weighted and 95% confidence intervals were calculated. Three adjusted logistic regression models were generated. To compare this sample to the general population of women, estimates from the Canadian Community Health Survey-Annual Component (2018) were used. RESULTS: Compared to the general population of women, a larger proportion of postpartum women reported a strong sense of community belonging. The odds of postpartum women with high self-rated physical health having high self-rated mental health were approximately seven times greater (aOR 6.9, 95% confidence interval [CI] 5.9, 8.1) than postpartum women with lower self-rated physical health. The absence of symptoms of postpartum depression (PPD) or generalized anxiety disorder (GAD) and high self-rated physical health were significantly associated with all three PMH outcomes. Frequent availability of maternal support was associated with greater odds of high life satisfaction (aOR 1.6, 95% CI 1.4, 1.9) and sense of community belonging (aOR 1.4, 95% CI 1.2, 1.6). CONCLUSIONS: Our study demonstrated that availability of maternal support, self-rated physical health and absence of symptoms of PPD or GAD were associated with PMH among postpartum women. As physical health had the strongest association with mental health, we encourage further examination of this relationship.

Infant bed sharing in Canada.

BACKGROUND: There is debate about the practice of bed sharing, which is defined as sharing a sleep surface with an infant. Most public health guidance in Canada, including the 2011 Joint Statement on Safe Sleep, advises parents against it because of an association with infant injury and death. However, proponents cite potential physical and psychological benefits, and evidence suggests that the risks associated with bed sharing are low in the absence of other risk factors. Until now, little has been known about the prevalence of and reasons for bed sharing in Canada. DATA AND METHODS: Canadian Community Health Survey data from 2015 and 2016 were used to estimate the prevalence of and reasons for bed sharing by selected characteristics among women aged 15 to 55 who had given birth in the past five years. Multivariate analysis examined factors independently associated with frequent bed sharing. RESULTS: An estimated 33% of women reported that their infant had frequently (every day or almost every day) shared a sleep surface with someone else; 27% had bed shared occasionally (once or twice a week, a few times a month or less than once a month) and 40% had never bed shared. Breastfeeding was the most common reason for bed sharing (39%), followed by facilitating the mother's or infant's sleep (29%). In multivariate analysis, age group, marital status, province or territory of residence, region of mother's birth and breastfeeding were significantly associated with frequent bed sharing. DISCUSSION: The data indicate that bed sharing is relatively common and suggest that parents are doing it for practical reasons. The results of this study will provide baseline data and inform policies and programs related to safe sleep practices.

Normative-referenced percentile values for physical fitness among Canadians.

BACKGROUND: This study developed age- and sex-specific normative-referenced percentile values for five physical fitness tests across a wide age range of Canadians, using a nationally representative sample. DATA AND METHODS: The data are from 5,188 Canadians (50.1% female) and were collected as part of cycle 5 of the Canadian Health Measures Survey (2016 to 2017). RESULTS: Males had slightly better cardiorespiratory fitness and substantially better grip strength, jumping height and jumping power scores than females, whereas females had better sit-and-reach flexibility. Among females, there were pronounced increases in jumping height (P50: 25%) and jumping power (P50: 58%) between ages 8 and 13, and in grip strength (P50: 193%) between ages 6 and 19. Performance gradually declined with age, beginning in adolescence for jumping ability and at approximately age 35 for grip strength. Among males, there were pronounced increases in jumping height (P50: 69%) and jumping power (P50: 233%) between ages 8 and 20, and in grip strength (P50: 365%) between ages 6 and 20. Performance gradually declined with age, beginning immediately after adolescence for jumping ability and at approximately age 30 for grip strength. Sit-and-reach flexibility remained relatively stable with age in both sexes. Cardiorespiratory fitness scores in both sexes declined steadily with age beginning (generally) at age 8, with a larger decline evident in females until age 18. DISCUSSION: These normative-referenced values for physical fitness could be useful for screening in public health and clinical practice.

Multiple sclerosis: Prevalence and impact.

This article provides new information about multiple sclerosis (MS) using the 2010/2011 Neurological Conditions Prevalence File, the 2011/2012 Survey of Neurological Conditions in Institutions in Canada, and the 2011 Survey on Living with Neurological Conditions in Canada. An estimated 93,500 Canadians living in private households and 3,800 residents of long-term care institutions had been diagnosed with MS. Prevalence estimates were 159 and 418 cases per 100,000 population for men and women, respectively; 2.6 women reported MS for every man with the condition. Among the household population, MS was generally diagnosed between the ages of 20 and 49 (82%). For the majority (68%), MS was their only neurological condition. The impact of MS included pain that prevented activities, impairments in mobility, cognition or sleep, and limitations in social functioning. Almost two-thirds (64%) stated that MS affected their lives at least moderately.

Duration and quality of sleep among Canadians aged 18 to 79.

This article provides recent estimates of the duration and quality of sleep of Canadian adults and of the percentage who adhere to sleep duration guidelines (7 to 9 hours per night at ages 18 to 64, and 7 to 8 hours per night at age 65 or older). The study is based on 10,976 respondents aged 18 to 79 from the 2007-to-2013 Canadian Health Measures Survey, a nationally representative, cross-sectional survey. Sleep duration and quality were self-reported. Mean sleep duration was 7.12 hours per night at ages 18 to 64 and 7.24 hours per night at ages 65 to 79. An estimated 65% of 18- to 64-year-olds and 54% of seniors slept the recommended number of hours per night. However, short sleep duration and poor sleep quality were relatively common. About a third slept fewer hours than recommended. At ages 18 to 64, an estimated 43% of men and 55% of women reported trouble going to sleep or staying asleep "sometimes/most of the time/all of the time"; the corresponding percentages at ages 65 to 79 were 40% and 59%.

Grip strength reference values for Canadians aged 6 to 79: Canadian Health Measures Survey, 2007 to 2013.

BACKGROUND: Grip strength is a measure of overall muscular strength and has been associated with disability, morbidity and mortality. Normative data are used to interpret an individual's grip strength measurements, but Canadian reference values are not available for a wide age range. DATA AND METHODS: The data pertain to 11,108 respondents aged 6 to 79 to the 2007-to-2013 Canadian Health Measures Survey, whose right-hand and left-hand grip strength were measured with a handgrip dynamometer. Quantile regression was used to develop reference equations for males and females for maximum, right-hand and left-hand grip strength for selected percentiles as a function of age, height and weight. RESULTS: Reference values for grip strength increased through childhood and adolescence, peaked around age 40, and then declined. Reference values were higher for males than for females; differences between the sexes were smaller during childhood than in adolescence and adulthood. Differences between reference values for maximum, right-hand and left-hand grip strength varied by age and sex. INTERPRETATION: Based on a large, healthy, nationally representative sample, reference equations were developed for grip strength of Canadians from childhood to older adulthood. These equations can be used to determine the reference values that correspond to an individual of a given age, sex, height and weight.

Reduced muscular strength among Canadians aged 60 to 79: Canadian Health Measures Survey, 2007 to 2013.

BACKGROUND: Reduced muscular strength is associated with an increased risk of all-cause, cardiovascular and non-cardiovascular mortality, heart attack and stroke. At older ages, reduced strength is associated with impaired mobility, risk of falls, and disability. Various criteria are used to determine reduced strength. DATA AND METHODS: Data on grip strength among 3,181 respondents aged 60 to 79 from the 2007 to 2013 Canadian Health Measures Survey were used to calculate the prevalence of reduced strength based on sex-specific percentile and t-score cut-points and cut-points of the Foundation for the National Institutes of Health. Logistic regression was used to identify significant associations between reduced strength and mobility, disability and self-rated health. RESULTS: Based on stricter criteria, the prevalence of reduced strength among household residents aged 60 to 79 ranged from 3% to 5%; based on less strict criteria, the prevalence ranged from 10% to 18%. Compared with people with normal strength, those with reduced strength had higher odds of impaired mobility (ranging from 3.40 to 8.33, depending on the cut-point), poor or fair self-rated health (2.19 to 4.20), and moderate-to-severe disability (2.21 to 2.60). INTERPRETATION: Estimates of the prevalence of reduced grip strength varied by cut-point. Reduced strength was significantly associated with impaired mobility, moderate-to-severe disability, and poor or fair self-rated health. Further research is required to determine if associations between reduced strength and other health outcomes vary by cut-point.

Epilepsy in Canada: Prevalence and impact.

This article provides information about the prevalence and impact of epilepsy, based on the 2010 and 2011 Canadian Community Health Surveys, the 2011/2012 Survey of Neurological Conditions in Institutions in Canada, and the 2011 Survey on Living with Neurological Conditions in Canada. An estimated 139,200 Canadians had epilepsy. Among the household population, epilepsy was generally diagnosed before age 30 (75%). For the majority of these people (64%), epilepsy was their only neurological condition. People with epilepsy were more than twice as likely to have been diagnosed with a mood disorder, compared with the general population (17% versus 7%), and eight times as likely to experience incontinence (34% versus 4%). Overall, an estimated 18% reported that their life was affected quite a bit or extremely by epilepsy; 44% felt that their life was impacted a little bit or moderately; and 39% felt that their life was not impacted at all. This study examined the impact of epilepsy on interactions with others, sleep, driving, education, and employment.

Exposure to industrial air pollutant emissions and lung function in children: Canadian Health Measures Survey, 2007 to 2011.

BACKGROUND: Long-term exposure to ambient air pollution has been associated with adverse effects on children's lung function. Few studies have examined lung function in relation to industrial emissions of air pollutants. DATA AND METHODS: This cross-sectional study was based on 2,833 respondents aged 6 to 18 for whom spirometry data were collected by the Canadian Health Measures Survey, 2007 to 2011. The weighted sum of industrial air emissions of nitrogen oxides (NOₓ) and fine particulate matter (PM2.5) within 25 km of the respondent's residence was derived using National Pollutant Release Inventory data. Multivariate linear regression was used to examine the relationship between NOₓ and PM2.5 emissions and forced vital capacity (FVC), the forced expiratory volume in 1 sec (FEV1), and the ratio of the two (FEV1/FVC). RESULTS: Industrial air emissions of NOₓ were not significantly associated with lung function among males or females. Emissions of PM2.5 were negatively associated with FEV1 and FEV1/FVC, but not FVC, among males. PM2.5 was not significantly related to lung function among females. INTERPRETATION: The associations that emerged between lung function and industrial emissions of PM2.5 among males were consistent with airway obstruction. Further research is warranted to investigate the gender differences observed in this study.

Alzheimer's disease and other dementias in Canada.

This article provides information on Alzheimer's disease and other dementias, using the 2010/2011 Canadian Community Health Survey, the 2011/2012 Survey of Neurological Conditions in Institutions in Canada, and the 2011 Survey on Living with Neurological Conditions in Canada. Among Canadians aged 45 or older, an estimated 0.8% in private households and 45% in long-term residential care facilities had a diagnosis of dementia. Prevalence rose with age. The vast majority of people with dementia in private households received assistance with medical care (81%), housework and home maintenance (83%), meal preparation (88%), emotional support (90%), transportation (92%), and managing care (92%). Among those receiving assistance, 85% relied, at least in part, on family, friends or neighbours. The primary caregiver tended to be a spouse (46%) or an adult child (44%), most of whom were daughters (71%). The majority of primary caregivers lived in the same household (83%) and provided daily care (86%).

Biochemical marker reference values across pediatric, adult, and geriatric ages: establishment of robust pediatric and adult reference intervals on the basis of the Canadian Health Measures Survey.

BACKGROUND: Biological covariates such as age and sex can markedly influence biochemical marker reference values, but no comprehensive study has examined such changes across pediatric, adult, and geriatric ages. The Canadian Health Measures Survey (CHMS) collected comprehensive nationwide health information and blood samples from children and adults in the household population and, in collaboration with the Canadian Laboratory Initiative on Pediatric Reference Intervals (CALIPER), examined biological changes in biochemical markers from pediatric to geriatric age, establishing a comprehensive reference interval database for routine disease biomarkers. METHODS: The CHMS collected health information, physical measurements, and biosamples (blood and urine) from approximately 12 000 Canadians aged 3-79 years and measured 24 biochemical markers with the Ortho Vitros 5600 FS analyzer or a manual microplate. By use of CLSI C28-A3 guidelines, we determined age- and sex-specific reference intervals, including corresponding 90% CIs, on the basis of specific exclusion criteria. RESULTS: Biochemical marker reference values exhibited dynamic changes from pediatric to geriatric age. Most biochemical markers required some combination of age and/or sex partitioning. Two or more age partitions were required for all analytes except bicarbonate, which remained constant throughout life. Additional sex partitioning was required for most biomarkers, except bicarbonate, total cholesterol, total protein, urine iodine, and potassium. CONCLUSIONS: Understanding the fluctuations in biochemical markers over a wide age range provides important insight into biological processes and facilitates clinical application of biochemical markers to monitor manifestation of various disease states. The CHMS-CALIPER collaboration addresses this important evidence gap and allows the establishment of robust pediatric and adult reference intervals.

Complex reference values for endocrine and special chemistry biomarkers across pediatric, adult, and geriatric ages: establishment of robust pediatric and adult reference intervals on the basis of the Canadian Health Measures Survey.

BACKGROUND: Defining laboratory biomarker reference values in a healthy population and understanding the fluctuations in biomarker concentrations throughout life and between sexes are critical to clinical interpretation of laboratory test results in different disease states. The Canadian Health Measures Survey (CHMS) has collected blood samples and health information from the Canadian household population. In collaboration with the Canadian Laboratory Initiative on Pediatric Reference Intervals (CALIPER), the data have been analyzed to determine reference value distributions and reference intervals for several endocrine and special chemistry biomarkers in pediatric, adult, and geriatric age groups. METHODS: CHMS collected data and blood samples from thousands of community participants aged 3 to 79 years. We used serum samples to measure 13 immunoassay-based special chemistry and endocrine markers. We assessed reference value distributions and, after excluding outliers, calculated age- and sex-specific reference intervals, along with corresponding 90% CIs, according to CLSI C28-A3 guidelines. RESULTS: We observed fluctuations in biomarker reference values across the pediatric, adult, and geriatric age range, with stratification required on the basis of age for all analytes. Additional sex partitions were required for apolipoprotein AI, homocysteine, ferritin, and high sensitivity C-reactive protein. CONCLUSIONS: The unique collaboration between CALIPER and CHMS has enabled, for the first time, a detailed examination of the changes in various immunochemical markers that occur in healthy individuals of different ages. The robust age- and sex-specific reference intervals established in this study provide insight into the complex biological changes that take place throughout development and aging and will contribute to improved clinical test interpretation.

Complex biological profile of hematologic markers across pediatric, adult, and geriatric ages: establishment of robust pediatric and adult reference intervals on the basis of the Canadian Health Measures Survey.

BACKGROUND: In a collaboration between the Canadian Laboratory Initiative on Pediatric Reference Intervals (CALIPER) and the Canadian Health Measures Survey (CHMS), we determined reference value distributions using an a priori approach and created a comprehensive database of age- and sex-stratified reference intervals for clinically relevant hematologic parameters in a large household population of children and adults. METHODS: The CHMS collected data and blood samples from 11 999 respondents aged 3-79 years. Hematology markers were measured with either the Beckman Coulter HmX or Siemens Sysmex CA-500 Series analyzers. After applying exclusion criteria and removing outliers, we determined statistically relevant age and sex partitions and calculated reference intervals, including 90% CIs, according to CSLI C28-A3 guidelines. RESULTS: Hematology marker values showed dynamic changes from childhood into adulthood as well as between sexes, necessitating distinct partitions throughout life. Most age partitions were necessary during childhood, reflecting the hematologic changes that occur during growth and development. Hemoglobin, red blood cell count, hematocrit, and indices (mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration) increased with age, but females had lower hemoglobin and hematocrit starting at puberty. Platelet count gradually decreased with age and required multiple sex partitions during adolescence and adulthood. White blood cell count remained relatively constant over life, whereas fibrinogen increased slightly, requiring distinct age and sex partitions. CONCLUSIONS: The robust dataset generated in this study has allowed observation of dynamic biological profiles of several hematology markers and the establishment of comprehensive age- and sex-specific reference intervals that may contribute to accurate monitoring of pediatric, adult, and geriatric patients.

Patterns of sedentary time and cardiometabolic risk among Canadian adults.

OBJECTIVE: The aim of this study is to examine the associations of total sedentary time and patterns of sedentary time with cardiometabolic biomarkers in a large representative sample of Canadian adults. METHODS: The study is based on 4935 adults aged 20-79years, from the 2007/09 and 2009/11 Canadian Health Measures Survey. Total sedentary time, patterns of sedentary time (≥20minute prolonged sedentary bouts, number of sedentary breaks), and moderate- to vigorous-intensity physical activity (MVPA) were accelerometer-derived. Waist circumference, systolic and diastolic blood pressure, high-density lipoprotein (HDL) cholesterol, and C-reactive protein were measured. Triglycerides, low-density lipoprotein (LDL) cholesterol, insulin, and glucose were also measured in a fasting sub-sample (n=2551). RESULTS: Total sedentary time and time in ≥20minute prolonged sedentary bouts were associated with higher insulin and lower diastolic blood pressure levels (P<0.05). On average, each additional 10 breaks/day was associated with 0.83 (95%CI: 1.35, 0.31) cm lower waist circumference, 0.32 (0.62, 0.02) mmHg lower systolic blood pressure, 0.01 (0.00, 0.02) mmol/l higher HDL-cholesterol, 3.72 (1.34, 6.13) % lower triglycerides, 0.57 (0.23, 0.92) % lower glucose, and 4.19 (1.80, 6.63) % lower insulin. CONCLUSION: These findings in a large representative sample of Canadian adults indicate that breaking up sedentary time may be particularly important for cardiometabolic health.

Parkinson's disease: Prevalence, diagnosis and impact.

This article provides information on Parkinson's disease, using the 2010/2011 Canadian Community Health Survey, the 2011/2012 Survey of Neurological Conditions in Institutions in Canada, and the 2011 Survey of Living with Neurological Conditions in Canada. An estimated 0.2% of Canadian adults in private households (55,000), and 4.9% of those in residential institutions (12,500), had Parkinson's disease. Younger age at symptom onset was associated with a longer period to disease diagnosis. As a result of the condition, 58% reported that social interactions were negatively affected, 61% reported out-of-pocket expenses, and 56% reported receiving assistance with activities such as housework, transportation or personal care. Among those receiving assistance, 84% relied at least in part on family, friends or neighbours. The primary informal caregiver tended to be a spouse (64%), female (62%), live in the same household (72%), and provide assistance on a daily basis (76%).

Nationally representative levels of selected volatile organic compounds in Canadian residential indoor air: population-based survey.

A comprehensive, population-based national indoor air survey was conducted in 2009-2011 in Canada. A total of 84 volatile organic carbons (VOCs) from 3218 houses, 546 apartments, and 93 other dwelling types were measured using passive sampling followed by thermal desorption GC/MS. A total of 12 VOCs were measured in both this study and the 1992 Canadian national study. Arithmetic means of VOCs in this study were 2-5 times lower than those in the 1992 study with the exception of a higher styrene level (1.13 µg · m(-3)). Comparing the geometric means of the 24 VOCs showed that levels for the VOCs in this study were comparable to those reported in Europe. They were generally within a factor of 2; 1,4-dichlorobenzene (0.21 µg · m(-3)) and 1,2,4-trimethylbenzene (0.51 µg · m(-3)) were noticeably lower in this study than in the European studies. There were 47 VOCs detected in more than 50% of Canadian households; 33 of them were higher in houses than in apartments for all nonsmoking homes, while only 4 were lower in houses than in apartments. A total of 11 of 47 VOCs were higher in smoking homes compared to nonsmoking homes, while the rest had similar levels. Principal component analysis identified several groups of VOCs with possible common sources.

Secondhand smoke exposure among Canadians: cotinine and self-report measures from the Canadian Health Measures Survey 2007-2009.

INTRODUCTION: Secondhand smoke (SHS) exposure is associated with numerous adverse health effects, including cancer, cardiovascular disease, asthma, respiratory infections, and decreased pulmonary function. This study provides population estimates of SHS exposure among the Canadian nonsmoking population based on self-report and urinary cotinine concentrations. METHODS: The 2007-2009 Canadian Health Measures Survey, a nationally representative cross-sectional survey, collected data from Canadians aged 6-79 years, and it includes self-report and urinary cotinine measures of tobacco smoke exposure (n = 4,455). RESULTS: An estimated 22% of nonsmokers reported being exposed to SHS every day or almost every day. Of those, 70% of children (6-11 years) and 48% of adolescents (12-19 years) had detectable cotinine levels compared with 23% of adults (20-79 years). An estimated 77% of nonsmokers exposed to SHS only in the home had detectable cotinine levels compared with 11% of nonsmokers exposed to SHS only outside the home. Of those exposed to SHS only in the home, a higher percentage of children (5.1%) had detectable cotinine levels compared with adults (3.1%). CONCLUSIONS: Despite well-known health risks associated with exposure to tobacco smoke, a substantial proportion of the Canadian population continues to be exposed to SHS. Higher percentages of certain subpopulations had detectable cotinine concentrations, including children, adolescents, and those exposed to SHS in the home.

The fractionalization of physical activity throughout the week is associated with the cardiometabolic health of children and youth.

BACKGROUND: The influence of the fractionalization of moderate- to vigorous- intensity physical activity (MVPA) throughout the week on the health of children is unknown. We compared cardiometabolic risk factors in physically active children who accumulated their weekly MVPA in different patterns. METHODS: We studied 745 participants aged 6-19 years. MVPA was measured using accelerometers over 7 days. Three groups were created: Insufficiently Active, <60 minutes/day of MVPA on average; Infrequently Active, ≥60 minutes/day of MVPA on average but exceeding the 60 minute target <5 days; and Frequently Active, ≥60 minutes/day MVPA on average and exceeding the 60 minute target ≥5 days. Percentile scores for 8 cardiometabolic risk factors were determined. RESULTS: The least favorable cardiometabolic risk factor profile was observed in the Insufficiently Active group. The Frequently Active group had more favorable (5-6 percentile unit difference) diastolic blood pressure, HDL-cholesterol, insulin resistance, and metabolic syndrome scores than the Infrequently Active group, although only the difference for insulin resistance was statistically significant (P < 0.05). These differences remained after controlling for the weekly volume of MVPA. CONCLUSION: The fractionalization of MVPA throughout the week was associated with insulin resistance.

The association between accelerometer-measured patterns of sedentary time and health risk in children and youth: results from the Canadian Health Measures Survey.

BACKGROUND: Self-reported screen time is associated with elevated health risk in children and youth; however, research examining the relationship between accelerometer-measured sedentary time and health risk has reported mixed findings. The purpose of this study was to examine the association between accelerometer-measured patterns of sedentary time and health risk in children and youth. METHODS: The results are based on 1,608 children and youth aged 6 to 19 years from the Canadian Health Measures Survey (2007-2009). Sedentary time was measured using the Actical accelerometer. Breaks in sedentary time and prolonged bouts of sedentary time lasting 20 to 120 minutes were derived for all days, weekend days and during the after-school period (i.e., after 3 pm on weekdays). Regression analyses were used to examine the association between patterns of sedentary time and body mass index (BMI), waist circumference, blood pressure and non-HDL cholesterol. RESULTS: Boys accumulated more sedentary time on weekdays after 3 pm and had a higher number of breaks in sedentary time compared to girls. Overweight/obese boys (aged 6-19 years) accumulated more sedentary time after 3 pm on weekdays (282 vs. 259 min, p < .05) and as prolonged bouts lasting at least 80 minutes (171 vs. 133 min, p < .05) compared to boys who were neither overweight nor obese. Prolonged bouts of sedentary time lasting at least 80 minutes accumulated after 3 pm on weekdays were positively associated with BMI and waist circumference in boys aged 11-14 years (p < .006). Each additional 60 min of sedentary time after 3 pm on weekdays was associated with a 1.4 kg·m-2 higher BMI and a 3.4 cm higher waist circumference in 11-14 year old boys. No sedentary pattern variables differed between girls who were not overweight or obese and those who were overweight/obese and none of the sedentary pattern variables were associated with any health markers in girls. CONCLUSIONS: The findings confirm results of other studies that reported accelerometer-measured sedentary time was not associated with health risk in children and youth. Even when the pattern and timing of sedentary time was examined relative to health markers, few associations emerged and were limited to boys aged 11-14 years.