Heather Orpana

BMI and mortality: results from a National Longitudinal Study of Canadian adults.

Although a clear risk of mortality is associated with obesity, the risk of mortality associated with overweight is equivocal. The objective of this study is to estimate the relationship between BMI and all‐cause mortality in a nationally representative sample of Canadian adults. A sample of 11,326 respondents aged ≥25 in the 1994/1995 National Population Health Survey (Canada) was studied using Cox proportional hazards models. A significant increased risk of mortality over the 12 years of follow‐up was observed for underweight (BMI <18.5; relative risk (RR) = 1.73, P < 0.001) and obesity class II+ (BMI >35; RR = 1.36, P <0.05). Overweight (BMI 25 to <30) was associated with a significantly decreased risk of death (RR = 0.83, P < 0.05). The RR was close to one for obesity class I (BMI 30–35; RR = 0.95, P >0.05). Our results are similar to those from other recent studies, confirming that underweight and obesity class II+ are clear risk factors for mortality, and showing that when compared to the acceptable BMI category, overweight appears to be protective against mortality. Obesity class I was not associated with an increased risk of mortality.

Long-term Association Between Leisure-time Physical Activity and Changes in Happiness: Analysis of the Prospective National Population Health Survey

Happiness is among the most fundamental of all human goals. Although the short-term association between physical activity and happiness is well known, the long-term associations are not. Data from the National Population Health Survey cycles conducted between 1994/1995 and 2008/2009 (cycles 1 through 8) were analyzed. Happy respondents were classified as physically active or inactive at baseline and then were followed up in subsequent cycles to examine their likelihood of becoming unhappy. Individuals who changed their activity level also were examined. After controlling for potential confounding factors, the authors found that leisure-time physical activity (LTPA) was associated with reduced odds of unhappiness after 2 years and 4 years. People who were inactive in 2 consecutive cycles were more than twice as likely to be unhappy as those who remained active in both cycles after 2 years. Compared with those who became active, inactive participants who remained inactive were also more likely to become unhappy. A change in LTPA from active to inactive was associated with increased odds of becoming unhappy 2 years later. This study suggests that LTPA has a long-term association with happiness. Changes in LTPA are associated with subsequent mood status.

Bodyweight, gender, and quality of life: a population-based longitudinal study

PurposeThe objective of the paper is to describe trajectories of health-related quality of life (HRQL) associated with categories of body mass index (BMI): underweight, normal weight, overweight, obese class I, and obese classes II and III.MethodsData come from the longitudinal Canadian National Population Health Survey. Analyses are based on data for 3,864 men and 4,745 women who were 40+ in 1998/1999 and followed through 2006/2007. HRQL was measured with the Health Utilities Index Mark 3. Multi-level growth modeling was used.ResultsHRQL declined with age. For men, there was a large HRQL decrement for being underweight; trajectories for all other BMI categories were very similar. For women being underweight was associated with higher HRQL at younger ages but lower at older ages. Otherwise, for women, HRQL was ordered from highest to lowest: normal, overweight, obese class I, and obese classes II and III.ConclusionsGiven that excess weight is a risk factor for mortality and the development of chronic conditions, the HRQL results for men are surprising. The HRQL results for women may reflect both the importance of body image on mental health and the health effects of excess weight.

Do stressors explain the association between income and declines in self-rated health? a longitudinal analysis of the national population health survey

Although there is considerable evidence documenting the relationship between lower socioeconomic status (SES) and poorer health, longitudinal research is needed to study mechanisms that may explain this relationship. This study investigated whether income was associated with decline in self-rated health over a 2-year period and whether stressors mediated part of this social gradient. Participants in the National Population Health Survey (NPHS) who rated their health as excellent, very good, or good in 1994 and1995 were followed over 2 years. Analyses demonstrated that individuals in the 2 lowest household income quintiles had significantly greater odds of experiencing a decline in health status as compared to the highest quintile. Seven of 8 reported stressors at baseline were each associated with a significantly increased odds of experiencing a decline in self-rated health. Furthermore, these stressors explained 16% and 10% of the relationship between the lowest and 2nd lowest income quintiles and decline in self-rated health, respectively. These results suggest that stressors may be 1 mechanism underlying the social gradient in health.

Hearing, mobility, and pain predict mortality: a longitudinal population-based study

OBJECTIVE Measures of health-related quality of life (HRQL), including the Health Utilities Index Mark 3 (HUI3) are predictive of mortality. HUI3 includes eight attributes, vision, hearing, speech, ambulation, dexterity, cognition, emotion, and pain and discomfort, with five or six levels per attribute that vary from no to severe disability. This study examined associations between individual HUI3 attributes and mortality. STUDY DESIGN AND SETTING Baseline data and 12 years of follow-up data from a closed longitudinal cohort study, the 1994/95 Canadian National Population Health Survey, consisting of 12,375 women and men aged 18 and older. A priori hypotheses were that ambulation, cognition, emotion, and pain would predict mortality. Cox proportional hazards regression models were applied controlling for standard determinants of health and risk factors. RESULTS Single-attribute utility scores for ambulation (hazard ratio [HR]=0.10; 0.04-0.22), hearing (HR=0.18; 0.06-0.57), and pain (HR=0.53; 0.29-0.96) were statistically significantly associated with an increased risk of mortality; ambulation and hearing were predictive for the 60+ cohort. CONCLUSION Few studies have identified hearing or pain as risk factors for mortality. This study is innovative because it identifies specific components of HRQL that predict mortality. Further research is needed to understand better the mechanisms through which deficits in hearing and pain affect mortality risks.

Intentions and actual physical activity behavior change in a community‐based sample of middle‐aged women: Contributions from the theory of planned behavior and self‐determination theory

Abstract This two‐study research assessed intentions and actual physical activity behavior change in a community‐based sample of Canadian middle‐aged women by integrating concepts from two strong and complimentary psychological theories: the Theory of Planned Behavior (TPB) and Self‐Determination Theory (SDT). Specific objectives were 1) to examine associations among TPB variables, motivation, and intention to increase physical activity and 2) to examine the relative influence of intentions and motivation on reported physical activity behavior change over time. First, in a cross‐sectional study, French‐speaking women (n = 109) recruited from community‐based facilities completed validated measures of TPB variables (attitudes, perceived behavioral control, subjective norms, and intentions) and motivation (autonomous and controlled). In a follow‐up longitudinal study, one hundred and forty‐nine English‐speaking women from similar facilities completed these measures and reported on actual physical activity at baseline and at six months. In the first study, attitudes, perceived behavioral control, and autonomous motivation were significantly associated with physical activity intentions. In the second study, attitudes, subjective norms, and autonomous motivation were significantly related to intentions to increase physical activity. In turn, intentions predicted change in physical activity behavior over time; however, the relationship was modest. Results highlight the role of intentions in physical activity behavior change among middleaged women and are discussed in light of current research and theory. Future research directions are proposed

Trajectories of health-related quality of life by socio-economic status in a nationally representative Canadian cohort

Background Mortality and morbidity have been shown to follow a ‘social gradient’ in Canada and many other countries around the world. Comparatively little, however, is known about whether ageing amplifies, diminishes or sustains socio-economic inequalities in health. Methods Growth curve analysis of seven cycles of the Canadian National Population Health Survey (n=13 682) for adults aged 20 and older at baseline (1994/95). The outcome of interest is the Health Utilities Index Mark 3, a measure of health-related quality of life (HRQL). Models include the deceased so as not to present overly optimistic HRQL values. Socio-economic position is measured separately by household-size-adjusted income and highest level of education attained. Results HRQL is consistently highest for the most affluent and the most highly educated men and women, and is lower, in turn, for middle and lower income and education groups. HRQL declines with age for both men and women. The rate of the decline in HRQL, however, was related neither to income nor to education for men, suggesting stability in the social gradient in HRQL over time for men. There was a sharper decline in HRQL for upper-middle and highest-income groups for women than for the poorest women. Conclusion HRQL is graded by both income and education in Canadian men and women. The grading of HRQL by social position appears to be ‘set’ in early adulthood and is stable through mid- and later life.

Neighborhood Walkability and Body Mass Index Trajectories: Longitudinal Study of Canadians

OBJECTIVES To assess the impact of neighborhood walkability on body mass index (BMI) trajectories of urban Canadians. METHODS Data are from Canadas National Population Health Survey (n = 2935; biannual assessments 1994-2006). We measured walkability with the Walk Score. We modeled body mass index (BMI, defined as weight in kilograms divided by the square of height in meters [kg/m(2)]) trajectories as a function of Walk Score and sociodemographic and behavioral covariates with growth curve models and fixed-effects regression models. RESULTS In men, BMI increased annually by an average of 0.13 kg/m(2) (95% confidence interval [CI] = 0.11, 0.14) over the 12 years of follow-up. Moving to a high-walkable neighborhood (2 or more Walk Score quartiles higher) decreased BMI trajectories for men by approximately 1 kg/m(2) (95% CI = -1.16, -0.17). Moving to a low-walkable neighborhood increased BMI for men by approximately 0.45 kg/m(2) (95% CI = 0.01, 0.89). There was no detectable influence of neighborhood walkability on body weight for women. CONCLUSIONS Our study of a large sample of urban Canadians followed for 12 years confirms that neighborhood walkability influences BMI trajectories for men, and may be influential in curtailing male age-related weight gain.

Canadian trends in opioid-related mortality and disabilityfrom opioid use disorder from 1990 to 2014 through thelens of the Global Burden of Disease Study

Introduction: Several regions in Canada have recently experienced sharp increases in opioid overdoses and related hospitalizations and deaths. This paper describes opioidrelated mortality and disability from opioid use disorder in Canada from 1990 to 2014 using data from the Global Burden of Disease (GBD) study.

Effectiveness of the CANRISK tool in the identification of dysglycemia in First Nations and Métis in Canada

INTRODUCTION First Nations/Métis populations develop diabetes earlier and at higher rates than other Canadians. The Canadian diabetes risk questionnaire (CANRISK) was developed as a diabetes screening tool for Canadians aged 40 years or over. The primary aim of this paper is to assess the effectiveness of the existing CANRISK tool and risk scores in detecting dysglycemia in First Nations/Métis participants, including among those under the age of 40. A secondary aim was to determine whether alternative waist circumference (WC) and body mass index (BMI) cut-off points improved the predictive ability of logistic regression models using CANRISK variables to predict dysglycemia. METHODS Information from a self-administered CANRISK questionnaire, anthropometric measurements, and results of a standard oral glucose tolerance test (OGTT) were collected from First Nations and Métis participants (n = 1479). Sensitivity and specificity of CANRISK scores using published risk score cut-off points were calculated. Logistic regression was conducted with alternative ethnicity-specific BMI and WC cut-off points to predict dysglycemia using CANRISK variables. RESULTS Compared with OGTT results, using a CANRISK score cut-off point of 33, the sensitivity and specificity of CANRISK was 68% and 63% among individuals aged 40 or over; it was 27% and 87%, respectively among those under 40. Using a lower cut-off point of 21, the sensitivity for individuals under 40 improved to 77% with a specificity of 44%. Though specificity at this threshold was low, the higher level of sensitivity reflects the importance of the identification of high risk individuals in this population. Despite altered cut-off points of BMI and WC, logistic regression models demonstrated similar predictive ability. CONCLUSION CANRISK functioned well as a preliminary step for diabetes screening in a broad age range of First Nations and Métis in Canada, with an adjusted CANRISK cutoff point for individuals under 40, and with no incremental improvement from using alternative BMI/WC cut-off points.