Strategies to optimize the impact of nutritional surveys and epidemiological studies

The development of nutrition and health guidelines and policies requires reliable scientific information. Unfortunately, theoretical considerations and empirical evidence indicate that a large percentage of science-based claims rely on studies that fail to replicate. The session "Strategies to Optimize the Impact of Nutrition Surveys and Epidemiological Studies" focused on the elements of design, interpretation, and communication of nutritional surveys and epidemiological studies to enhance and encourage the production of reliable, objective evidence for use in developing dietary guidance for the public. The speakers called for more transparency of research, raw data, consistent data-staging techniques, and improved data analysis. New approaches to collecting data are urgently needed to increase the credibility and utility of findings from nutrition epidemiological studies. Such studies are critical for furthering our knowledge and understanding of the effects of diet on health.

The impact of late career job loss on myocardial infarction and stroke: a 10 year follow up using the health and retirement survey.

BACKGROUND: Involuntary job loss is a major life event associated with social, economic, behavioural, and health outcomes, for which older workers are at elevated risk. OBJECTIVE: To assess the 10 year risk of myocardial infarction (MI) and stroke associated with involuntary job loss among workers over 50 years of age. METHODS: Analysing data from the nationally representative US Health and Retirement Survey (HRS), Cox proportional hazards analysis was used to estimate whether workers who suffered involuntary job loss were at higher risk for subsequent MI and stroke than individuals who continued to work. The sample included 4301 individuals who were employed at the 1992 study baseline. RESULTS: Over the 10 year study frame, 582 individuals (13.5% of the sample) experienced involuntary job loss. After controlling for established predictors of the outcomes, displaced workers had a more than twofold increase in the risk of subsequent MI (hazard ratio (HR) = 2.48; 95% confidence interval (CI) = 1.49 to 4.14) and stroke (HR = 2.43; 95% CI = 1.18 to 4.98) relative to working persons. CONCLUSION: Results suggest that the true costs of late career unemployment exceed financial deprivation, and include substantial health consequences. Physicians who treat individuals who lose jobs as they near retirement should consider the loss of employment a potential risk factor for adverse vascular health changes. Policy makers and programme planners should also be aware of the risks of job loss, so that programmatic interventions can be designed and implemented to ease the multiple burdens of joblessness.

The association of HIV counseling and testing with HIV risk behaviors in a random population-based survey in Kisumu, Kenya.

HIV testing has been promoted as a key HIV prevention strategy in low-resource settings, despite studies showing variable impact on risk behavior. We sought to examine rates of HIV testing and the association between testing and sexual risk behaviors in Kisumu, Kenya. Participants were interviewed about HIV testing and sexual risk behaviors. They then underwent HIV serologic testing. We found that 47% of women and 36% of men reported prior testing. Two-thirds of participants who tested HIV-positive in this study reported no prior HIV test. Women who had undergone recent testing were less likely to report high-risk behaviors than women who had never been tested; this was not seen among men. Although rates of HIV testing were higher than seen in previous studies, the majority of HIV-infected people were unaware of their status. Efforts should be made to increase HIV testing among this population.

A map of North America : from the latest surveys and maps /

Relief shown pictorially.

Children's health and indoor air quality in primary schools and homes in Portugal-Study design

The main aim of the research project "On the Contribution of Schools to Children's Overall Indoor Air Exposure" is to study associations between adverse health effects, namely, allergy, asthma, and respiratory symptoms, and indoor air pollutants to which children are exposed to in primary schools and homes. Specifically, this investigation reports on the design of the study and methods used for data collection within the research project and discusses factors that need to be considered when designing such a study. Further, preliminary findings concerning descriptors of selected characteristics in schools and homes, the study population, and clinical examination are presented. The research project was designed in two phases. In the first phase, 20 public primary schools were selected and a detailed inspection and indoor air quality (IAQ) measurements including volatile organic compounds (VOC), aldehydes, particulate matter (PM2.5, PM10), carbon dioxide (CO2), carbon monoxide (CO), bacteria, fungi, temperature, and relative humidity were conducted. A questionnaire survey of 1600 children of ages 8-9 years was undertaken and a lung function test, exhaled nitric oxide (eNO), and tear film stability testing were performed. The questionnaire focused on children's health and on the environment in their school and homes. One thousand and ninety-nine questionnaires were returned. In the second phase, a subsample of 68 children was enrolled for further studies, including a walk-through inspection and checklist and an extensive set of IAQ measurements in their homes. The acquired data are relevant to assess children's environmental exposures and health status.

Cultural and social factors and quality of life of Maori in advanced age. Te puawaitanga o nga tapuwae kia ora tonu - Life and living in advanced age: a cohort study in New Zealand (LiLACS NZ)

AIM: To establish 1) the socioeconomic and cultural profile and 2) correlates of quality of life (QOL) of Maori in advanced age. METHOD: A cross sectional survey of a population based cohort of Maori aged 80-90 years, participants in LiLACS NZ, in the Rotorua and Bay of Plenty region of New Zealand. Socioeconomic and cultural engagement characteristics were established by personal interview and QOL was assessed by the SF-12. RESULTS: In total 421 (56%) participated and 267 (63%) completed the comprehensive interview. Maori lived with high deprivation areas and had received a poor education in the public system. Home ownership was high (81%), 64% had more than 3 children still living and social support was present for practical tasks and emotional support in 82%. A need for more practical help was reported by 21%. Fifty-two percent of the participants used te reo Maori me nga tikanga (Maori language and culture) daily. One in five had experienced discrimination and one in five reported colonisation affecting their life today. Greater frequency of visits to marae/sacred gathering places was associated with higher physical health-related QOL. Unmet need for practical help was associated with lower physical health-related QOL. Lower mental health-related QOL was associated with having experienced discrimination. CONCLUSION: Greater language and cultural engagement is associated with higher QOL for older Maori and unmet social needs and discrimination are associated with lower QOL.

The prevalence and characteristics associated with excessive daytime sleepiness among Australian workers

OBJECTIVE: To estimate the prevalence of excessive daytime sleepiness (EDS) and its associated factors in a mixed population of employed Australian workers. METHODS: Study participants (n = 707) were volunteers from various Melbourne workplaces, participating in a workplace physical activity program in 2008. Daytime sleepiness was assessed using the Epworth Sleepiness Scale (ESS), with EDS defined as ESS scores >10. RESULTS: In this population of adult employees (40.0% male; mean age 40.2 ± 10.4 years), prevalence of EDS was 16.0%. Characteristics associated with EDS and higher ESS scores were age, higher body mass index, markers of poorer diet, and markers of poorer mental health. CONCLUSIONS: Excessive daytime sleepiness is potentially an important contributor to lower productivity and poorer mental health in the workplace. Our finding suggests that workplace health programs aimed at improving diet and body weight may also help alleviate EDS.

The mediating role of dietary factors and leisure time physical activity on socioeconomic inequalities in body mass index among Australian adults

BACKGROUND: The relationship between socioeconomic position and obesity has been clearly established, however, the extent to which specific behavioural factors mediate this relationship is less clear. This study aimed to ascertain the contribution of specific dietary elements and leisure-time physical activity (LTPA) to variations in obesity with education in the baseline (1990-1994) Melbourne Collaborative Cohort Study (MCCS).

METHODS: 18, 489 women and 12, 141 men were included in this cross-sectional analysis. A series of linear regression models were used in accordance with the products of coefficients method to examine the mediating role of alcohol, soft drink (regular and diet), snacks (healthy and sweet), savoury items (healthy and unhealthy), meeting fruit and vegetable guidelines and LTPA on the relationship between education and body mass index (BMI).

RESULTS: Compared to those with lowest educational attainment, those with the highest educational attainment had a 1 kg/m2 lower BMI. Among men and women, 27% and 48%, respectively, of this disparity was attributable to differences in LTPA and diet. Unhealthy savoury item consumption and LTPA contributed most to the mediated effects for men and women. Alcohol and diet soft drink were additionally important mediators for women.

CONCLUSIONS: Diet and LTPA are potentially modifiable behavioural risk factors for the development of obesity that contribute substantially to inequalities in BMI. Our findings highlight the importance of specific behaviours which may be useful to the implementation of effective, targeted public policy to reduce socioeconomic inequalities in obesity.

Measuring the accuracy of self-reported height and weight in a community-based sample of young people

BACKGROUND: Self-reported anthropometric data are commonly used to estimate prevalence of obesity in population and community-based studies. We aim to: 1) Determine whether survey participants are able and willing to self-report height and weight; 2) Assess the accuracy of self-reported compared to measured anthropometric data in a community-based sample of young people.

METHODS: Participants (16-29 years) of a behaviour survey, recruited at a Melbourne music festival (January 2011), were asked to self-report height and weight; researchers independently weighed and measured a sub-sample. Body Mass Index was calculated and overweight/obesity classified as ≥25 kg/m². Differences between measured and self-reported values were assessed using paired t-test/Wilcoxon signed ranks test. Accurate report of height and weight were defined as <2 cm and <2 kg difference between self-report and measured values, respectively. Agreement between classification of overweight/obesity by self-report and measured values was assessed using McNemar's test.

RESULTS: Of 1405 survey participants, 82% of males and 72% of females self-reported their height and weight. Among 67 participants who were also independently measured, self-reported height and weight were significantly less than measured height (p=0.01) and weight (p<0.01) among females, but no differences were detected among males. Overall, 52% accurately self-reported height, 30% under-reported, and 18% over-reported; 34% accurately self-reported weight, 52% under-reported and 13% over-reported. More females (70%) than males (35%) under-reported weight (p=0.01). Prevalence of overweight/obesity was 33% based on self-report data and 39% based on measured data (p=0.16).

CONCLUSIONS: Self-reported measurements may underestimate weight but accurately identified overweight/obesity in the majority of this sample of young people.

Risk of cardiovascular disease and diabetes in a working population with sedentary occupations

OBJECTIVE: To assess the prevalence of risk factors and risk for cardiovascular disease and Type 2 diabetes in employees with sedentary occupations enrolled in a workplace health-promotion program. METHODS: Participants (n = 762) were recruited from ten Melbourne workplaces, participating in a physical activity program. Demographic, behavioral, biomedical, and physical measurements were collected. RESULTS: The majority of employees were not meeting recommended guidelines for physical activity (62%), fruit intake (70%), vegetable intake (86%), body mass index (58%), or waist circumference (53%). Most had intermediate (53%) or high (7%) risk of developing Type 2 diabetes. CONCLUSIONS: The majority of Australian adults in sedentary occupations were not meeting guidelines for a number of chronic disease risk factors and a substantial proportion were unaware of their increased risk. This study supports the potential of chronic disease risk factor detection and intervention programs in the workplace.

Self-efficacy, imagery use, and adherence during injury rehabilitation

Previous observational studies examining imagery, self-efficacy, and adherence during injury rehabilitation have been cross-sectional and thus have not provided a clear representation of what occurs over the course of the rehabilitation period. The objectives of this research were (1) to examine the temporal patterns of imagery, self-efficacy, and rehabilitation adherence during an 8-week rehabilitation program and (2) to identify the time-order relationships between imagery, self-efficacy, and adherence. The design of the study was prospective and observational. 90 injured people (n=57 males; n=33 females) aged 18-78 years attending an injury rehabilitation clinic participated. The main outcome measures were imagery (cognitive, motivational, and healing), self-efficacy (task and coping), and rehabilitation adherence (duration, quality, and frequency). Results indicated that task efficacy, imagery use, and adherence levels remained stable, while coping efficacy declined over time. During the course of rehabilitation, moderate to strong reciprocal relationships existed between self-efficacy and adherence to rehabilitation. Weak to moderate relationships were found between imagery use and rehabilitation adherence. The results of this study can be used to inform the development of interventions steeped in self-efficacy and imagery aimed at improving rehabilitation adherence and treatment outcome.

Overweight among New Zealand adolescents: associations with ethnicity and deprivation

OBJECTIVES: The objectives of the current study are: to describe the prevalence of overweight/obesity among New Zealand adolescents and to describe the demographic characteristics, including neighbourhood deprivation, associated with overweight/obesity. METHODS: Data for the current study were collected as part of Youth'07, a national survey of the health and well-being of 9 107 New Zealand secondary school students (approximate ages 13 to 17 years). Students answered a comprehensive, multimedia survey about their health and wellbeing and were weighed and measured for height. Small area deprivation was measured by the New Zealand Deprivation Index, based on the student's residential address. RESULTS: One in ten adolescents was obese and an additional 24% were overweight. Body size was significantly associated with small area deprivation (p<0.001) and ethnicity (p<0.001). Furthermore, the association between socioeconomic deprivation and body mass index (BMI) was moderated by ethnicity (p=0.035 for interaction term.) A positive association between BMI and socioeconomic deprivation was observed for Pacific students, Māori students and European students, but not for Asian students and students of other ethnicities. CONCLUSIONS: Our findings demonstrate a high prevalence of overweight/obesity among New Zealand adolescents, particularly for Pacific Island adolescents, Māori adolescents, and those living in areas of high deprivation.