The impact of updated clinical blood pressure guidelines on hypertension prevalence among children and adolescents.

Background: To date, population estimates of hypertension prevalence among children and adolescents in Canada have been based on clinical guidelines in the National High Blood Pressure Education Program's 2004 Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents (NHBPEP 2004). In 2017, the American Academy of Pediatrics published updated guidelines in Clinical Practice Guideline for Screening and Management of High Blood Pressure in Children and Adolescents (AAP 2017), followed by Hypertension Canada in 2020 with its publication of Comprehensive Guidelines for the Prevention, Diagnosis, Risk Assessment, and Treatment of Hypertension in Adults and Children (HC 2020). This study compares national child and adolescent hypertension prevalence estimates based on NHBPEP 2004, AAP 2017 and HC 2020. Data and methods: Six cycles of data spanning 2007 to 2019 from the Canadian Health Measures Survey were used to compare blood pressure (BP) categories and the prevalence of hypertension by sex and age group under all sets of guidelines for children and adolescents aged 6 to 17. The impact of applying AAP 2017 across time and selected characteristics, the resulting reclassification into a higher BP category under AAP 2017, and differences in hypertension prevalence resulting from applying HC 2020 versus AAP 2017 were examined. Results: Prevalence of Stage 1 hypertension was higher among children and adolescents aged 6 to 17 under AAP 2017 and HC 2020 than under NHBPEP 2004. Overall hypertension prevalence was also higher, and obesity was a major factor associated with being reclassified into a higher BP category under AAP 2017. Interpretation: Implementation of AAP 2017 and HC 2020 is associated with significant changes in the epidemiology of hypertension. Understanding the impact of applying updated clinical guidelines may help inform population surveillance efforts to track hypertension prevalence among Canada's children and adolescents.

Intersecting risk factors for physical inactivity among Canadian adults.

Background: On average, 45% of Canadian adults meet the recommended 150 minutes per week of moderate-to-vigorous physical activity. This singular statistic masks a wide range of adherence levels among different groups within the population. The purpose of this paper is to determine how sex, age, and family arrangement intersect with known risk factors for physical inactivity to identify groups within the Canadian population most at risk of not meeting the physical activity recommendation. Methods: Using six combined cycles of the Canadian Health Measures Survey (from 2007 to 2019), this study examines how the percentage of Canadian males and females aged 18 to 79 years meeting the physical activity recommendation differs across sociodemographic, family arrangement, and health factors. Logistic regression was used to examine whether the association between specific factors and adherence to the physical activity recommendation differed by sex. Latent class analysis was used to identify sex-specific combinations of sociodemographic, family arrangement and health-related factors within the Canadian population that are associated with varying levels of adherence to the physical activity recommendation. Results: More males met the physical activity recommendation compared with females (49% versus 38%). Latent classes with the lowest adherence to the physical activity recommendation (19% among females and 29% among males) primarily included those who were single or married with no children and who had a high probability of having many risk factors for physical inactivity, including being older, having a lower education, having lower income, smoking, having central adiposity, and having poor or fair self-rated general health. Latent classes with the highest adherence to the physical activity recommendation (61% among females and 67% among males) primarily included individuals with no spouse and no children and who had a low probability of having any risk factors for physical inactivity. For females, an additional class (32% of which met the physical activity recommendation) comprised young single mothers who had several risk factors for physical inactivity, including having low income, smoking and having central adiposity. Interpretation: Understanding how risk factors for physical inactivity intersect with sex, age, and family arrangement may inform strategies aimed at increasing physical activity among those who are most vulnerable.

Differences in birthweight by maternal and paternal nativity status in Canada.

BACKGROUND: Parental nativity, as well as duration of residence of foreign-born parents in the host country, has been shown to be associated with size at birth. However, most studies have focused on maternal nativity status only and have not accounted for important characteristics of both parents. OBJECTIVE: To explore whether maternal and paternal nativity and length of residence (LOR) are independently associated with birthweight for gestational age in a representative sample of infants in Canada. METHODS: We compared mean differences in sex- and gestational age-standardised birthweight z-score by nativity status of both parents in a nationally representative sample of 130,532 singleton infants born between May 2004 and May 2006 to mothers residing in Canada. We categorised parental nativity status into four groups (both parents Canada-born, mother only foreign-born, father only foreign-born and both parents foreign-born) and parents' LOR into three (both ≤10 years, only one parent ≤10 years and both >10 years). We estimated mean differences in birthweight z-score and their 95% confidence intervals in linear regression models adjusted for parity, parents' ages, education, ethnicity and marital status of the mother. RESULTS: Compared with babies of Canada-born couples, those of two foreign-born parents had on average smaller birthweight z-score, -0.23 (95% CI -0.28, -0.25). However, after adjustment, the mean difference in z-score was -0.02 (95% CI -0.05, 0.00). Infants born to parents who had both resided in Canada for ≤10 years had a unadjusted mean difference in z-score of -0.27 (95% CI -0.29, -0.26), compared infants whose parents were both Canada-born, but the difference became negligible (-0.02, 95% CI -0.04, 0.01) after adjustment. CONCLUSION: The birthweight differences by parental nativity or length of residence observed in our study population could be attributed to differences in the distribution of other parental characteristics that affect birthweight.

Compliance with precautions to reduce the spread of COVID-19 in Canada.

Background: Throughout the COVID-19 pandemic, Canadian public health officials have mandated and recommended precautions to slow the spread of COVID-19. This study examined which population groups were less compliant with precautions, such as mask-wearing and self-isolating, and where they were located in Canada. Data and methods: Results are from the Canadian COVID-19 Antibody and Health Survey, a national survey aimed at estimating how many Canadians who were older than one year and living in private households had antibodies in their blood against the SARS-CoV-2 virus. Questionnaire data were collected in the 10 provinces and 3 territorial capitals, from November 2020 to April 2021. Respondents were asked about compliance with precautions related to COVID-19. Weighted prevalences and logistic regression models were used to identify which population groups were less compliant with precautions to prevent the spread of COVID-19, and where they were located in Canada. Results: Significant differences in compliance with precautions were found by sex, region, urban versus rural location, age, income, presence of chronic conditions, household size and work status. With covariate adjustment, Canadians who were less compliant with precautions were males, those living in the territorial capitals, those in rural areas, and people aged 34 and younger (compared with people aged 65 and older). Additional differences were found when analyzing compliance with consistently recommended precautions compared with those usually recommended. Interpretation: As Canada continues to navigate the waves of the pandemic, and with the emergence of new variants, precautions are still being mandated or recommended in many jurisdictions and locations. Continuing to understand which population groups were less compliant in earlier waves and where they were located in Canada can be beneficial to ongoing and future public health efforts to slow the transmission of COVID-19.

COVID-19 infection in the Canadian household population.

Background: Certain population groups face a disproportionate burden of exposure to COVID-19. This study examined characteristics of Canadians living in private households in fall 2020 and winter 2021 who had been infected with COVID-19. Data and Methods: With an online questionnaire and an at-home finger-prick blood test, the Canadian COVID-19 Antibody and Health Survey was designed to estimate the seroprevalence of COVID-19 infection among people in private households in Canada. Data were collected from respondents aged 1 or older in the 10 provinces and the three territorial capitals, from November 2020 to April 2021. Descriptive statistics and logistic regression were used to identify characteristics that were associated with being seropositive for a past COVID-19 infection. Gender differences in observed associations were examined. Results: After covariate adjustment, younger age and visible minority status were associated with an increased likelihood of being seropositive for a past COVID-19 infection. For males, having a visible minority status, having less education and living in a multi-unit dwelling increased the likelihood of being seropositive. Females were more likely to have been seropositive if they worked in health care in direct contact with others. Interpretation: As Canada navigates the fifth and possibly a sixth wave of the pandemic, understanding who was more likely to be infected in earlier waves can help ongoing public health efforts to stop the transmission of COVID-19.

Data profile: Expanding the research potential of the Canadian Health Measures Survey using paired respondent data.

The family environment is an important influence on the health and behaviours of children. Few large-scale datasets include detailed and objectively measured health data about multiple individuals from the same family who are living in the same household. The Canadian Health Measures Survey (CHMS) is a repeating, cross-sectional survey that selects two members of a household-a child and a randomly selected older member of the household aged 12 to 79 years-with at least one child aged 3 to 11 years in residence. These paired respondent records, available in the CHMS relationship files, provide unique opportunities to researchers interested in examining associations between two members of the same household for health behaviours and outcomes. A range of pairings are captured in the relationship files (e.g., parent and child, siblings, grandchild and grandparent) with birth parent-child pairs being the most common. These paired respondent data are an important analytical asset of the CHMS and enhance the research potential of the survey significantly.

Perinatal health among foreign versus native-born mothers in Canada: variations across outcomes and cohorts.

BACKGROUND: To examine perinatal health differences between foreign-born and native-born mothers in Canada across multiple outcomes and two cohorts 10 years apart. METHODS: Using 94 896 and 131 271 births in the 1996 and 2006 Canadian Census-Birth Cohort, respectively, we estimated risk ratios and risk differences of preterm birth (PTB), small-for-gestational age (SGA), large-for-gestational age (LGA), stillbirth and infant mortality between foreign-born and Canadian-born mothers. RESULTS: In the 1996 cohort, we observed no important differences in adverse outcomes between foreign-born and native-born mothers. In the 2006 cohort, however, foreign-born mothers had lower risks of PTB, LGA, stillbirth, and infant mortality and a higher risk of SGA on both the relative and absolute scales. Lowered risk of PTB among foreign-born mothers in the 2006 cohort was also observed within Caucasian, East Asian, Southeast Asian and South Asian mothers. Favourable outcomes associated with foreign-born status in the 2006 cohort were negatively graded by duration of residence in Canada among immigrant mothers. CONCLUSIONS: Differences in perinatal health by maternal foreign-born status varied across cohorts and a more pronounced 'healthy migrant' effect was observed among more recent migrants. The native-born mothers' perinatal health over time and a more restrictive/selective immigration policy in recent years would explain our results.

Changing trends in thyroid cancer incidence in Canada: A histologic examination, 1992 to 2016.

BACKGROUND: Age-standardized incidence rates (ASIRs) of thyroid cancer (TC) have increased in many parts of the world, primarily because of increased papillary TC detection. While rapid increases in TC incidence have also been reported in Canada, an analysis of incidence and survival by histologic subtype has been lacking. Moreover, recent data points in Canada suggest that the era of rapid annual increases may have ended. DATA AND METHODS: Data are from the Canadian Cancer Registry, the Canadian Vital Statistics-Death Database and an analytic file linking the two. Annual percent changes (APCs) in incidence and mortality rates are estimated using Joinpoint regression. Net survival (NS) is derived using the Pohar Perme estimator. RESULTS: Among females, TC ASIRs decreased by 3.0% annually from 2012 to 2016, following years of rapid growth. Among males, a long period of rapid increase ended in 2012 with no subsequent decline. For both sexes the overall incidence trend was driven by changes over time in papillary TC and incidence trends in non-papillary TC varied significantly. From 1992 to 2016, TC mortality rates were stable among females and increased slightly among males (APC = 1.2). Five-year NS was higher among papillary cases (99%) than among non-papillary cases (80%) and among females (99%) than among males (94%). Overall, five-year NS increased by 2.1 percentage points from the period from 1992 to 1996 to the period from 2010 to 2014. DISCUSSION: The results of this study confirm the central role of papillary TC cases in TC incidence and survival trends in Canada. Given recent changes in trend and TC management guidelines, projected increases in TC rates after 2016 could be re-examined.

Exercise and screen time during the COVID-19 pandemic.

BACKGROUND: The objective of this paper is to describe the exercise and changes in screen time habits, and their relationship with health, among participants of the Canadian Perspectives Survey Series (CPSS). DATA AND METHODS: Between March 29th and April 3rd 2020, CPSS participants (n = 4,524) reported whether they were exercising outdoors or indoors and whether they increased, decreased or maintained their TV, Internet and video game use. Participants also reported their self-perceived general and mental health. RESULTS: More women reported very good or excellent mental health if they were exercising outdoors (54%) compared with those who were not (41%). More women reported very good or excellent general health if they were exercising outdoors (75%) compared with those who were not (49%), with the same trend evident for those exercising indoors (69%) compared to those who were not (62%). More men (65%) and women (62%) rated their mental and general health as very good or excellent if they maintained or decreased TV time compared with those who increased TV time (57% and 43%, respectively), with the same evident for Internet use in women only (maintained/decreased: 61% versus increased: 44%). More men (63%) and women (52%) rated their mental health as very good or excellent if they maintained or decreased video game time compared with those who increased video game time (48% and 29%, respectively). More men and women reported very good or excellent mental and general health if they increased none or one type of screen and/or were exercising outdoors compared with those who increased 2 or 3 types of screens and who were not exercising outdoors, with the exception of general health among men. DISCUSSION: Maintaining opportunities for outdoor exercise and limiting screen time may promote better mental and general health during periods of confinement.

Socioeconomic disparities in life and health expectancy among the household population in Canada.

BACKGROUND: Life expectancy (LE) and health expectancy have increased throughout much of the world. However, these gains have not been shared equally across all population groups. Socioeconomic disparities exist, though varied methodologies and data sources have made it difficult to ascertain changes over time in Canada. DATA AND METHODS: The 1996 and 2011 Canadian Census Health and Environment Cohorts, with a five-year mortality follow-up, were used to estimate the LE of the household population at ages 25 and 65, according to individual-level education and income. Health status was measured by the Health Utilities Index Mark 3 instrument in two national population health surveys and was used to adjust LE to estimate health-adjusted life expectancy (HALE). Disparities in LE and HALE, and differences between cohorts, were examined. RESULTS: LE, HALE and the ratio of HALE to LE were greater at higher levels of education or income. A stepwise gradient was also observed by level of education within and across income quintiles, with people in the lowest combined education and income categories at the greatest disadvantage. Disparities were wider in the 2011 cohort compared with the 1996 cohort, but not necessarily to the same extent for both sexes or at different ages. DISCUSSION: In Canada, education-related and income-related disparities in life and health expectancy persist and may be wider than they were in the past. This underscores the importance of ongoing data development for routine monitoring of trends in mortality and morbidity, which can, in turn, inform policy development and planning to advance health equity.

Life expectancy of First Nations, Métis and Inuit household populations in Canada.

BACKGROUND: The Truth and Reconciliation Commission of Canada has called upon the federal government to provide data on a number of health indicators, including life expectancy among First Nations people, Métis and Inuit. In Canada, estimating the life expectancy of Indigenous populations is methodologically challenging since death registrations do not usually collect information on whether the deceased was Indigenous. For the first time in Canada, a series of census-mortality linked datasets has been created that can be used to estimate life expectancies among Indigenous household populations enumerated by a census. DATA AND METHODS: Life expectancy is the average number of years a person at a given age would be expected to live if the mortality rates observed for a specific period persisted into the future. For this study, abridged period life tables (based on five-year age groups) were calculated for self-reported First Nations, Métis, Inuit and non-Indigenous males and females. RESULTS: Life expectancy was substantially and consistently shorter for First Nations, Métis and Inuit household populations compared with the non-Indigenous household population across all time periods. In 2011, life expectancy at age 1 for the male household population was 72.5 years for First Nations, 76.9 years for Métis, 70.0 years for Inuit and 81.4 years for non-Indigenous people. Among the female household population, life expectancy at age 1 was 77.7 years for First Nations, 82.3 years for Métis, 76.1 years for Inuit and 87.3 for non-Indigenous people. DISCUSSION: With the creation of a series of census-mortality linked datasets, it is now possible to produce national mortality and life expectancy estimates starting at age 1 for Indigenous household populations. The routine monitoring of longevity by population group can inform policy development and planning intended to advance health equity.

Trends in mortality inequalities among the adult household population.

BACKGROUND: The routine measurement of population health status indicators like mortality is important to assess progress in the reduction of inequalities. Previous studies of mortality inequalities have relied on area-based measures of socioeconomic indicators. A new series of census-mortality linked datasets has been created in Canada to quantify mortality inequalities based on individual-level data and examine whether these inequalities have changed over time. DATA AND METHODS: This study used the 1991, 1996, 2001, 2006, and 2011 Canadian Census Health and Environment Cohorts (CanCHECs) with five years of mortality follow-up. It estimated age-standardized mortality rates by sex according to income quintile and highest level of educational attainment categories for the household population aged 25 or older. Absolute and relative measures of mortality inequality were also estimated. RESULTS: Men had a greater reduction in mortality rates over time compared with women, regardless of income or education level. Absolute income-related mortality inequality decreased for men but increased for women over time, while relative income-related inequality increased for both sexes. Education-related mortality inequality for women followed the same pattern as income, though the absolute mortality difference for men remained roughly unchanged over the period. DISCUSSION: Mortality inequalities by income and education persist in Canada, and have increased for women. Further research to determine the mechanisms underlying these trends could help address the complex challenge of reducing health inequalities in Canada.

Cohort profile: The Canadian Census Health and Environment Cohorts (CanCHECs).

The Canadian Census Health and Environment Cohorts (CanCHECs) are population-based linked datasets of the household population at the time of census collection. The CanCHECs combine data from respondents to the long-form census or the National Household Survey between 1991 and 2011 with administrative health data (e.g., mortality, cancer incidence, hospitalizations, emergency ambulatory care) and annual mailing address postal codes. The CanCHEC datasets are rich national data resources that can be used to measure and examine health inequalities across socioeconomic and ethnocultural dimensions for different periods and locations. These datasets can also be used to examine the effects of exposure to environmental factors on human health. Because of their large size, the CanCHECs are an excellent resource for examining rare health outcomes and small population groups. They are ideally suited for environmental health research because of their geographic coverage across all regions of Canada, their long follow-up periods and their linkage to annual postal code history.

Blood pressure and hypertension.

BACKGROUND: Hypertension, or high blood pressure, is a major cause of disability and the leading risk factor for death around the world. Ongoing surveillance is necessary to monitor and assess the population burden of hypertension in Canada. DATA AND METHODS: Using measured data from the Canadian Health Measures Survey, this analysis estimates average systolic blood pressure (BP), average diastolic BP, and hypertension prevalence, awareness, treatment and control in the population aged 20 to 79 years in the period from 2012 to 2015 by sex and age group. Crude and age-standardized overall estimates for 2007-2009, 2009-2011, 2012-2013 and 2014-2015 are also presented. RESULTS: Among adults aged 20 to 79 years, 24% of males and 23% of females had hypertension, defined as measured BP ≥140/90 mm Hg or past-month use of antihypertensive medication. Hypertension prevalence increased to 40% for males and 32% for females when the BP threshold was lowered to ≥130/80 mm Hg. Among adults, 84% of people with hypertension were aware of their condition, 80% of hypertensive people were treated for their condition, and 66% had controlled hypertension (measured BP ⟨140/90 mm Hg), though those aged 20 to 39 were less likely than older age groups to be aware, treated or controlled. Crude and age-standardized rates remained fairly stable during the period from 2007-2009 to 2014-2015. DISCUSSION: Hypertension prevalence among adults has remained stable over time in Canada, and hypertension awareness, treatment and control have remained high. However, rates of awareness, treatment and control are lower among younger adults. This finding highlights the importance of initiatives to encourage this population to have their blood pressure checked and treated.

Risk factors for hypertension in Canada.

BACKGROUND: Hypertension (or high blood pressure) affects almost one in four adults in Canada. Quantifying risk factors associated with hypertension may help to inform prevention efforts. DATA AND METHODS: Data from the first four cycles of the Canadian Health Measures Survey (including 13,407 respondents) were used to identify hypertension status by systolic and diastolic blood pressure levels and the use of antihypertensive medications. Logistic regression analysis was employed to estimate the association between six cardiovascular risk factors (individually and as a composite score) and hypertension. RESULTS: Engaging in less than 150 minutes per week of moderate-to-vigorous physical activity, eating fruits and vegetables fewer than five times per day, being overweight or obese, having diabetes, and having chronic kidney disease were all independently associated with an increased risk of hypertension. When these factors were combined into a risk score, there was a linear increase in the predicted risk of hypertension with each additional risk factor. The predicted prevalence of hypertension for those with all six risk factors was 55% in women and 44% in men aged 20 to 39 years, and 80% in women and 76% in men aged 70 to 79 years. Being overweight or obese, consuming fruits and vegetables less often, being inactive, and having diabetes contributed to the largest attributable fractions for hypertension in the Canadian population. DISCUSSION: Physical activity, diet, body mass index, the presence of diabetes, and the presence of chronic kidney disease were strong risk factors for hypertension. Many of these risk factors are modifiable and highlight targets for future prevention strategies.

Sociodemographic characteristics associated with thyroid cancer risk in Canada.

BACKGROUND: Thyroid cancer incidence in Canada has increased rapidly over the past 25 years. This study examines thyroid cancer incidence and relative risk according to individual-level sociodemographic characteristics in two population-based cohorts. DATA AND METHODS: The analysis uses data from the 1991 and 2001 Canadian Census Health and Environment Cohorts (CanCHECs). Using nine years of cancer follow-up for both time periods, age-standardized incidence rates of thyroid cancer were estimated by sex-with sex-specific estimates produced by immigrant status, ethnicity, educational attainment and family income-and by histology type. All characteristics were included in sex-specific standard Cox proportional hazard models to examine the relative risk of thyroid cancer and the relative risk of papillary versus non-papillary thyroid cancer. RESULTS: A significant increase over time in thyroid cancer incidence was observed for both sexes, and across all characteristics. Immigrant status and ethnicity were each independently associated with the risk of thyroid cancer, with immigrant men and women and East and Southeast Asian women at higher risk. Men and women who had a postsecondary diploma or higher or who were in the highest income quintile were at increased risk of being diagnosed with papillary thyroid cancer, but not with non-papillary thyroid cancer. DISCUSSION: While increased detection has played a role in the rising incidence of thyroid cancer in Canada, it does not fully account for the greater relative risk among the immigrant population and certain ethnic groups. More research is needed to better understand the determinants of the increased risk in these populations.

Health-adjusted life expectancy in Canada.

BACKGROUND: Over the past century, life expectancy at birth in Canada has risen substantially. However, these gains in the quantity of life say little about gains in the quality of life. DATA AND METHODS: Health-adjusted life expectancy (HALE), an indicator of quality of life, was estimated for the household and institutional populations combined every four years from 1994/1995 to 2015. Health status was measured by the Health Utilities Index Mark 3 instrument in two national population health surveys, and was used to adjust life expectancy. The percentage of the population living in health-related institutions was estimated based on the Census of Population. Attribute-deleted HALE was calculated to determine how various aspects of health status contributed to the differences between life expectancy and HALE. RESULTS: HALE has increased in Canada. Greater gains among males have narrowed the gap between males and females. The ratio of HALE to life expectancy changed little for males, and a marginal improvement was observed for females aged 65 or older. Mobility problems and pain, the latter mainly among females, accounted for an increased share of the burden of ill health over time. Exclusion of the institutional population significantly increased the estimates of HALE and yielded higher ratios of HALE to life expectancy. DISCUSSION: Although people are living longer, the share of years spent in good functional health has remained fairly constant. Data for both the household and institutional populations are necessary for a complete picture of health expectancy in Canada.

Factors associated with hypertension control among older Canadians.

BACKGROUND: In Canada, hypertension control is significantly less likely in older women taking antihypertensive medication than in older men. This study examines factors that may explain some of the differences in hypertension control between women and men. DATA AND METHODS: The analysis is based on data collected for 2,111 adults aged 60 to 79 who were treated for hypertension in the first four cycles of the Canadian Health Measures Survey. Hypertension, treatment and control were estimated based on measured systolic and diastolic blood pressure and on the Drug Identification Numbers of antihypertensive medications. Risk factors included health behaviours, comorbidities and a family history of hypertension. Sex-specific logistic regression models examined associations between risk factors and hypertension control. RESULTS: The systolic blood pressure of women taking antihypertensive medication was higher than that of men, regardless of hypertension control. For women, older age and diabetes were significantly associated with poorer hypertension control, while older age, ethnicity, diabetes, no cardiovascular disease, and nonsteroidal anti-inflammatory drug use were significant for men. DISCUSSION: Based on current blood pressure targets, women and men aged 60 to 79 taking antihypertensive medication in Canada continue to differ in control and factors associated with control. Further research to better understand the underlying cause of these associations may help reduce disparities in hypertension control rates between women and men in Canada.

Parent-Child association in body weight status.

BACKGROUND: The prevalence of overweight and obesity among children and adults has risen in Canada. Studies suggest that parent obesity is a risk factor for overweight and obesity in children. This analysis examines associations between biological parent and child body mass index (BMI) in a nationally representative sample of Canadian children. DATA AND METHODS: The analysis is based on data collected for 1,563 children aged 6 to 10 in the first three cycles of the Canadian Health Measures Survey (2007 to 2013). BMI was calculated using measured height and weight. Pearson correlation, logistic, and linear regression analyses examined associations between biological parent and child BMI and obesity status, controlling for other risk factors. RESULTS: Biological parent and child BMI were correlated. When risk factors were taken into account, a child's average BMI increased as their parent's BMI increased. Parent BMI explained 2% of the variance in boys' BMI and 12% of the variance in girls' BMI. Boys and girls with a biological parent who was obese were at increased risk of being overweight or obese. Girls were also at increased risk of being overweight or obese if a biological parent was overweight. INTERPRETATION: Children's body weight status is associated with that of at least one of their biological parents. Having an obese parent increases the risk of overweight or obesity among children in Canada.

Parent-Child association in physical activity and sedentary behaviour.

BACKGROUND: Parents influence the physical activity and sedentary behaviour of their children. This analysis examines associations between parental role modeling and support and children's physical activity and sedentary behaviour. DATA AND METHODS: The sample consists of 1,328 biological parent-child pairs from the first three cycles of the Canadian Health Measures Survey (2007 through 2013). Data on physical activity and sedentary behaviour were collected using a questionnaire and by accelerometer. Pearson correlation and linear regression analyses were completed to examine associations between parents' and children's measured physical activity and sedentary time and reported screen-based activities. Analyses were adjusted for variables indicating parental support and household lifestyle characteristics. RESULTS: Accelerometer-measured physical activity and sedentary time were correlated in all parent-child pairs. Parents' measured moderate-to-vigorous physical activity (MVPA) was associated with children's MVPA (ß = 0.28, p < 0.001). For every 20-minute increase in a parent's MVPA, the child's MVPA increased by 5 to 10 minutes. Parents' measured sedentary time was associated with that of their daughters on weekends, and with that of their sons during the after-school period. Parents' reported screen time was associated with that of their daughters. INTERPRETATION: This study confirms parents' influence on their children's physical activity. Parental role modeling and support have independent effects on a child's level of physical activity.