Prospective associations of four nutrient profiles with weigh gain, overweight and obesity risk

Background

Nutrient Profiling Systems (NPSs), including the UK Food Standards Agency NPS and its variants are used to classify foods according to their nutritional composition for nutrition policies. The prospective validity of these NPSs requires however further investigation. The study investigates the associations of the original Food Standards Agency (FSA)-NPS and three variants - the Food Standards Australia New Zealand Nutrient Profiling Scoring Criterion (NPSC), the Health Star Rating (HSR) system NPS and the French NPS (HCSP-NPS) -, which are used as a basis for nutrition policies, with weight status.

Methods

Dietary indices based on each of the four investigated NPSs applied at the food level were computed at the individual level to characterize the diet quality of 71,178 French individuals from the NutriNet-Santé cohort. Associations of these Dietary Indices (DIs) (as tertiles) with weight gain were assessed using multivariable mixed models, and with overweight and obesity risks using multivariable Cox models.

Results

For the four NPSs, participants with a lower diet nutritional quality were more likely to have an increase in body mass index over time (median follow-up of 3.14 ± 2.76 years, beta coefficients positive, all p ≤ 0.0001), and an increased risk of overweight (HRT3vs.T1=1.27 [1.17-1.37] for the HCSP-DI, followed by the original FSA-DI with HRT3vs.T1=1.18 [1.09-1.28], the NPSC-DI with HRT3vs.T1=1.14 [1.06-1.24] and the HSR-DI, HRT3vs.T1=1.12 [1.04-1.21]). Whilst differences were small, the HCSP-DI appeared to show significantly greater association with risk of overweight compared to other NPS.

Conclusions

Less healthy diets defined using the Food Standards Agency-NPS and related systems were all associated with weight gain and overweight risk. Demonstrating this association with health outcomes is an important indicator of one validity dimension of NPSs and supports their use in public policies for the prevention of diet-related chronic diseases.

Key messages

Nutrient profile models of foods and beverages allow capturing the nutritional quality of diets and are prospectively associated with weight gain and obesity. The French NPS which underpins the front-of-pack Nutri-Score appeared to have a small but significant higher performance.

Kids in space: Measuring children's residential neighborhoods and other destinations using activity space GPS and wearable camera data

INTRODUCTION

Defining the boundary of children's 'neighborhoods' has important implications for understanding the contextual influences on child health. Additionally, insight into activities that occur outside people's neighborhoods may indicate exposures that place-based studies cannot detect. This study aimed to 1) extend current neighborhood research, using data from wearable cameras and GPS devices that were worn over several days in an urban setting; 2) define the boundary of children's neighborhoods by using leisure time activity space data; and 3) determine the destinations visited by children in their leisure time, outside their neighborhoods.

METHOD

One hundred and fourteen children (mean age 12y) from Wellington, New Zealand wore wearable cameras and GPS recorders. Residential Euclidean buffers at incremental distances were paired with GPS data (thereby identifying time spent in different places) to explore alternative definitions of neighborhood boundaries. Children's neighborhood boundary was at 500 m. A newly developed software application was used to identify 'destinations' visited outside the neighborhood by specifying space-time parameters. Image data from wearable cameras were used to determine the type of destination.

RESULTS

Children spent over half of their leisure time within 500 m of their homes. Children left their neighborhood predominantly to visit school (for leisure purposes), other residential locations (e.g. to visit friends) and food retail outlets (e.g. convenience stores, fast food outlets). Children spent more time at food retail outlets than at structured sport and in outdoor recreation locations combined.

CONCLUSION

Person-centered neighborhood definitions may serve to better represent children's everyday experiences and neighborhood exposures than previous methods based on place-based measures. As schools and other residential locations (friends and family) are important destinations outside the neighborhood, such destinations should be taken into account. The combination of image data and activity space GPS data provides a more robust approach to understanding children's neighborhoods and activity spaces.

Children's everyday exposure to food marketing: an objective analysis using wearable cameras

Background

Over the past three decades the global prevalence of childhood overweight and obesity has increased by 47%. Marketing of energy-dense nutrient-poor foods and beverages contributes to this worldwide increase. Previous research on food marketing to children largely uses self-report, reporting by parents, or third-party observation of children’s environments, with the focus mostly on single settings and/or media. This paper reports on innovative research, Kids’Cam, in which children wore cameras to examine the frequency and nature of everyday exposure to food marketing across multiple media and settings.

Methods

Kids’Cam was a cross-sectional study of 168 children (mean age 12.6 years, SD = 0.5) in Wellington, New Zealand. Each child wore a wearable camera on four consecutive days, capturing images automatically every seven seconds. Images were manually coded as either recommended (core) or not recommended (non-core) to be marketed to children by setting, marketing medium, and product category. Images in convenience stores and supermarkets were excluded as marketing examples were considered too numerous to count.

Results

On average, children were exposed to non-core food marketing 27.3 times a day (95% CI 24.8, 30.1) across all settings. This was more than twice their average exposure to core food marketing (12.3 per day, 95% CI 8.7, 17.4). Most non-core exposures occurred at home (33%), in public spaces (30%) and at school (19%). Food packaging was the predominant marketing medium (74% and 64% for core and non-core foods) followed by signs (21% and 28% for core and non-core). Sugary drinks, fast food, confectionary and snack foods were the most commonly encountered non-core foods marketed. Rates were calculated using Poisson regression.

Conclusions

Children in this study were frequently exposed, across multiple settings, to marketing of non-core foods not recommended to be marketed to children. The study provides further evidence of the need for urgent action to reduce children’s exposure to marketing of unhealthy foods, and suggests the settings and media in which to act. Such action is necessary if the Commission on Ending Childhood Obesity’s vision is to be achieved.

Electronic supplementary material

The online version of this article (doi:10.1186/s12966-017-0570-3) contains supplementary material, which is available to authorized users.

Dietary under-reporting: what foods and which meals are typically under-reported?

Little objective information exists regarding which foods and meals are typically under-reported during retrospective self-reported dietary assessments. Automated wearable cameras record dietary behaviours in free-living settings and allow the context of under-reporting to be explored. As part of a study to validate image-assisted dietary assessment, 40 participants wore a wearable camera on days before three image-assisted 24-h dietary recalls. The foods and meals were typically under-reported, and the environmental and social contexts of under-reporting were assessed. Under-reporting occurred most frequently during afternoon snacks (75/265 foods), dinner (54/265 foods) and breakfast (44/265 foods). Snack foods were most frequently unreported during afternoon snacks, and condiments were most frequently under-reported at breakfasts. No clear pattern of social or environmental contexts for under-reporting was observed. Wearable cameras can identify when specific foods are likely to be under-reported during retrospective dietary assessments. Problematic foods and meals identified could be given additional attention during dietary assessments.

Kelston Beverages Pilot Study: Rationale, design and implementation of a community and school based intervention to reduce sugary drink consumption among children and youth

The Kelston Beverages Study was designed to increase awareness of the sugar content of sugary drinks, the poor health consequences that high intake of these drinks have, and inform on ways to reduce intake of students. The aims of this pilot study were to refine interventions and processes designed to raise awareness of the harms that sugar sweetened beverages (SSBs) have on health, and to reduce their consumption among the youth of a small West Auckland suburb. There were three arms to this interventional study, one in schools, another in community organisations (churches, sports clubs and community groups), and the final arm is in the local retail sector. The school arm was the most extensive component and initially involved a survey of children's knowledge and consumption of sugar sweetened beverages (SSBs) using a brief questionnaire. The study evaluated any SSB policies in schools and for schools that did not have policies, opportunities were scoped to develop and implement them; a canteen AUDIT focussed particularly on beverages was carried out; and finally a student partnered social marketing exercise was undertaken that comprised 2 competitions, one to design a poster, and another to write and perform a rap. Children were re-surveyed at the completion of the intervention (7 months later) to determine change in knowledge and self-reported consumption of SSBs. Both the community organisations and retail arms of this study focussed on raising awareness into the harmful effects of SSBs and establishing healthy beverage policy in the respective organisations. Promising results with regards to acceptability, feasibility, and recruitment as well as valuable learnings with regard to process support the development of a proposal to conduct a cluster randomised trial of the interventions successfully tested in this pilot study.

Sweetened and unsweetened non-alcoholic beverages in New Zealand: assessment of relative availability, price, serve size, and sugar content

BACKGROUND

Sweetened beverages are a major contributor to sugar intakes in New Zealand, yet little information exists regarding the retail environment and the characteristics of sweetened and unsweetened beverages available for purchase.

AIM

Our aim was to assess the availability, price, serve size and sugar content of sweetened and unsweetened non-alcoholic beverages available for purchase in New Zealand supermarkets. We also review and summarise the evidence for policy options relating to beverage availability, price, serve size and sugar content.

METHODS

Data on all non-alcoholic beverages available for purchase in two large Auckland supermarkets were sourced from Nutritrack, a brand- specific packaged food composition database.

RESULTS

Of 680 beverages available for sale in 2012, less than one in five (17%) was low-energy or unsweetened. However, low-energy options were cheaper, on average, than their sugar-sweetened counterparts (by approximately one third). The sugar content of beverages available ranged from zero to 23 g/100 mL. Some beverages contained more than 80 g of sugar (16 teaspoons) per single serve. National and international evidence suggests that increasing prices of fizzy drinks could reduce consumption, but long-term impacts on obesity and population health are unknown. Little evidence exists regarding other strategies to create healthier retail food environments.

CONCLUSION

The vast majority of beverages available for purchase in New Zealand supermarkets are either sugar-sweetened or contain naturally occurring sugars. Options to decrease availability and reduce consumption of sweetened beverages should be urgently explored.

Under-reporting remains a key limitation of self-reported dietary intake: an analysis of the 2008/09 New Zealand Adult Nutrition Survey

BACKGROUND/OBJECTIVES

The most recent New Zealand Adult Nutrition Survey 2008/09 (ANS 08/9) revealed a decrease in reported energy intakes (EIs) compared with the previous 1997 National Nutrition Survey (NNS97). Conversely, measured body weights increased over the same period. We conducted an analysis on the ANS 08/9 data sets to evaluate reported EIs.

SUBJECTS/METHODS

Analysis was conducted on data from 3919 (1715 men and 2204 women aged > or = 15 years) survey participants who completed the 24-h dietary recall in the ANS 08/9. Under-reporting was assessed using the ratio of reported EI to estimated resting metabolic rate (EI:RMRest), and a cutoff limit of <0.9 (EI:RMRest) was used to identify low energy reporters (LERs). Results were examined by gender, body size, age and ethnicity.

RESULTS

The mean EI:RMRest (s.e.m.) was 1.34 (0.02) for men, and 1.23 (0.02) for women. Overall, 21% of men and 25% of women were classified as LERs. There was a greater prevalence of LERs among people with overweight (25%), or obesity (30%) than people with normal body weight (16%, P<0.001). The oldest age group (> or =65 years) had a greater prevalence of LERs (33%) compared with all other age groups (19-24%, P<0.001). Pacific people had a greater prevalence of LERs (33%) compared with Maori (26%, P=0.007) and European (23%, P<0.001). Compared with the NNS97, a substantial increase in the prevalence of LERs was evident in most subgroups.

CONCLUSIONS

Under-reporting of EI will continue to be a major limitation of nutrition surveys without technological innovation. Care should be taken when interpreting EI data.

Monitoring the health-related labelling of foods and non-alcoholic beverages in retail settings

Food labelling on food packaging has the potential to have both positive and negative effects on diets. Monitoring different aspects of food labelling would help to identify priority policy options to help people make healthier food choices. A taxonomy of the elements of health-related food labelling is proposed. A systematic review of studies that assessed the nature and extent of health-related food labelling has been conducted to identify approaches to monitoring food labelling. A step-wise approach has been developed for independently assessing the nature and extent of health-related food labelling in different countries and over time. Procedures for sampling the food supply, and collecting and analysing data are proposed, as well as quantifiable measurement indicators and benchmarks for health-related food labelling.

Monitoring the availability of healthy and unhealthy foods and non-alcoholic beverages in community and consumer retail food environments globally

Retail food environments are increasingly considered influential in determining dietary behaviours and health outcomes. We reviewed the available evidence on associations between community (type, availability and accessibility of food outlets) and consumer (product availability, prices, promotions and nutritional quality within stores) food environments and dietary outcomes in order to develop an evidence-based framework for monitoring the availability of healthy and unhealthy foods and non-alcoholic beverages in retail food environments. Current evidence is suggestive of an association between community and consumer food environments and dietary outcomes; however, substantial heterogeneity in study designs, methods and measurement tools makes it difficult to draw firm conclusions. The use of standardized tools to monitor local food environments within and across countries may help to validate this relationship. We propose a step-wise framework to monitor and benchmark community and consumer retail food environments that can be used to assess density of healthy and unhealthy food outlets; measure proximity of healthy and unhealthy food outlets to homes/schools; evaluate availability of healthy and unhealthy foods in-store; compare food environments over time and between regions and countries; evaluate compliance with local policies, guidelines or voluntary codes of practice; and determine the impact of changes to retail food environments on health outcomes, such as obesity.

Monitoring the price and affordability of foods and diets globally

Food prices and food affordability are important determinants of food choices, obesity and non-communicable diseases. As governments around the world consider policies to promote the consumption of healthier foods, data on the relative price and affordability of foods, with a particular focus on the difference between 'less healthy' and 'healthy' foods and diets, are urgently needed. This paper briefly reviews past and current approaches to monitoring food prices, and identifies key issues affecting the development of practical tools and methods for food price data collection, analysis and reporting. A step-wise monitoring framework, including measurement indicators, is proposed. 'Minimal' data collection will assess the differential price of 'healthy' and 'less healthy' foods; 'expanded' monitoring will assess the differential price of 'healthy' and 'less healthy' diets; and the 'optimal' approach will also monitor food affordability, by taking into account household income. The monitoring of the price and affordability of 'healthy' and 'less healthy' foods and diets globally will provide robust data and benchmarks to inform economic and fiscal policy responses. Given the range of methodological, cultural and logistical challenges in this area, it is imperative that all aspects of the proposed monitoring framework are tested rigorously before implementation.

Feasibility of a SenseCam-assisted 24-h recall to reduce under-reporting of energy intake

BACKGROUND/OBJECTIVES

The SenseCam is a camera worn on a lanyard around the neck that automatically captures point-of-view images in response to movement, heat and light (every 20-30 s). This device may enhance the accuracy of self-reported dietary intake by assisting participants' recall of food and beverage consumption. It was the objective of this study to evaluate if the wearable camera, SenseCam, can enhance the 24-h dietary recall by providing visual prompts to improve recall of food and beverage consumption.

SUBJECT/METHODS

Thirteen volunteer adults in Oxford, United Kingdom, were recruited. Participants wore the SenseCam for 2 days while continuing their usual daily activities. On day 3, participants' diets were assessed using an interviewer-administered 24-h recall. SenseCam images were then shown to the participants and any additional dietary information that participants provided after viewing the images was recorded. Energy and macronutrient intakes were compared between the 24-h recall and 24-h recall+SenseCam.

RESULTS

Data from 10 participants were included in the final analysis (8 males and 2 females), mean age 33 ± 11 years, mean BMI 25.9 ± 5.1 kg/m(2). Viewing the SenseCam images increased self-reported energy intake by approximately 1432 ± 1564 kJ or 12.5% compared with the 24-h recall alone (P=0.02). The increase was predominantly due to reporting of 41 additional foods (241 vs 282 total foods) across a range of food groups. Eight changes in portion size were made, which resulted in a negligible change to energy intake.

CONCLUSIONS

Wearable cameras are promising method to enhance the accuracy of self-reported dietary assessment methods.

Use of electronic sales data to tailor nutrition education resources for an ethnically diverse population

BACKGROUND

Nutrition education may be most effective when personally tailored. Individualised electronic supermarket sales data offer opportunities to tailor nutrition education using shopper's usual food purchases. The present study aimed to use individualised electronic supermarket sales data to tailor nutrition resources for an ethnically diverse population in a large supermarket intervention trial in New Zealand.

METHODS

Culturally appropriate nutrition education resources (i.e. messages and shopping lists) were developed with the target population (through two sets of focus groups) and ethnic researchers. A nutrient database of supermarket products was developed using retrospective sales data and linked to participant sales to allow tailoring by usual food purchases. Modified Heart Foundation Tick criteria were used to identify 'healthier' products in the database suitable for promotion in the resources. Rules were developed to create a monthly report listing the tailored and culturally targeted messages to be sent to each participant, and to produce automated, tailored shopping lists.

RESULTS

Culturally targeted nutrition messages (n = 864) and shopping lists (n = 3 formats) were developed. The food and nutrient database (n = 3000 top-selling products) was created using 12 months of retrospective sales data, and comprised 60%'healthier' products. Three months of baseline sales data were used to determine usual food purchases. Tailored resources were successfully mailed to 123 Māori, 52 Pacific and 346 non-Māori non-Pacific participants over the 6-month trial intervention period.

CONCLUSIONS

Electronic supermarket sales data can be used to tailor nutrition education resources for a large number of ethnically diverse supermarket shoppers.

Children and television watching: a qualitative study of New Zealand parents' perceptions and views

BACKGROUND

Television (TV) viewing is one of the most pervasive sedentary pursuits among children and adolescents. Research studies have shown that higher TV viewing hours are associated with a number of negative effects such as being overweight and obese, attention and behavioural problems, and impaired academic performance. Most interventions to reduce time spent watching TV have been school-based and little is known about the strategies that families use to control TV watching time.

METHODS

Six focus groups with Māori, Pacific and non-Māori non-Pacific parents were conducted to examine New Zealand parents' perceptions of their children's TV watching. Focus groups explored attitudes towards TV viewing, strategies used to reduce viewing, and opinion on two different electronic monitors that can be used to restrict TV viewing. Focus group discussions were transcribed and a content analysis was conducted.

RESULTS

Parents described TV as playing a dominant role in their family's lives, and highlighted several barriers to reducing children's TV viewing, such as parents not willing to reduce their own TV watching, a lack of safe alternatives to TV and the need to use TV as a babysitting tool. Limiting access to TV, making TV viewing a reward and finding alternative activities were current strategies parents employed to limit TV viewing; however, the barriers highlighted by parents make implementing such strategies difficult. Attitudes towards electronic monitor use to reduce TV viewing were mixed, but suggest further investigation of these devices is needed.

CONCLUSIONS

Electronic devices that restrict the amount and content of TV viewing have some potential to support interventions and merit further investigation. It is imperative for interventions aimed at reducing TV viewing to consider the role TV plays within a family context, ensuring parental perceptions around the benefits and barriers of reducing TV are accounted for.

An evaluation of metabolic risks for coronary death in the Asia Pacific region

AIM

To investigate the generalizability of current definitions of the metabolic syndrome in Asia-Pacific populations, and whether information on metabolic risk factors could be better used to discriminate fatal coronary heart disease (CHD) risk.

METHODS AND RESULTS

Analyses were performed on individual participant data from 26 cohorts involving 329, 166 participants from the Asia Pacific region. Sensitivity and specificity estimates for CHD death associated with cut-points as defined by the U.S. National Cholesterol Education Panel (NCEP) were determined for component risk factors of a modified NCEP-defined metabolic syndrome. Five cohorts (6437 subjects, 53 CHD deaths) measuring all five risk factors at baseline were used to evaluate the association between the metabolic syndrome and CHD, and to compare risk discrimination using a definition including each risk factor as a continuous variable. Sensitivity and specificity estimates for risk factor cut-points varied considerably by region (Asia versus Australia/New Zealand) and moderately by sex. The adjusted hazard ratio for CHD death associated with the modified NCEP-defined metabolic syndrome was 2.05 (95%CI, 1.13-3.72). On receiver operator characteristic analysis, the area-under-the-curve for CHD death was 0.586 (95%CI: 0.439-0.732) for the modified NCEP-defined metabolic syndrome, and 0.733, 95%CI: 0.664-0.802) for a definition including each of the metabolic risk factors in their continuous form.

CONCLUSION

Specific cut-points for metabolic risk factors are not generalizable between populations. This finding is not restricted to measures of central obesity. A multivariable definition of the metabolic syndrome including all risk factors as continuous variables improves CHD risk discrimination substantially.

Chitosan for overweight or obesity

BACKGROUND

Chitosan, a deacetylated chitin, is a dietary supplement reported to decrease body weight. It is widely available over the counter worldwide and although evaluated in a number of trials its efficacy remains in dispute.

OBJECTIVES

To assess the effects of chitosan as a treatment for overweight and obesity.

SEARCH STRATEGY

We searched electronic databases (MEDLINE, EMBASE, BIOSIS, CINAHL, The Cochrane Library), specialised web sites (Controlled Trials, IBIDS, SIGLE, Reuter's Health Service, Natural Alternatives International, Pharmanutrients), bibliographies of relevant journal articles, and contacted relevant authors and manufacturers. Last searches were completed in March 2004.

SELECTION CRITERIA

Trials were included in the review if they were randomised controlled trials of chitosan a minimum of four weeks duration in adults who were overweight or obese. Authors of included studies were contacted for additional information where appropriate.

DATA COLLECTION AND ANALYSIS

Details from eligible trials were extracted independently by two reviewers using a standardised data extraction form. Differences in data extraction were resolved by consensus. Continuous data were expressed as weighted mean differences and standard deviations. The pooled effect size was computed by using the inverse variance weighted method.

MAIN RESULTS

Fourteen trials including a total of 1131 participants met the inclusion criteria. No trial to date has measured the effect of chitosan on mortality or morbidity. Analyses including all trials indicated that chitosan preparations result in a significantly greater weight loss (weighted mean difference -1.7 kg; 95% confidence interval (CI) -2.1 to -1.3 kg; P < 0.00001), decrease in total cholesterol (-0.2 mmol/L; 95% CI -0.3 to -0.1; P < 0.00001), decrease in systolic (-5.9 mmHg; 95% CI -7.3 to -4.6; P < 0.0001) and diastolic (-3.4 mmHg; 95% CI -4.4 to -2.4; P < 0.00001) blood pressure compared with placebo. There were no clear differences between intervention and control groups in terms of frequency of adverse events or in faecal fat excretion. However, the quality of many studies was sub-optimal and analyses restricted to studies that met allocation concealment criteria, were larger, or of longer duration showed that such trials produced substantially smaller decreases in weight and total cholesterol.

AUTHORS' CONCLUSIONS

There is some evidence that chitosan is more effective than placebo in the short-term treatment of overweight and obesity. However, many trials to date have been of poor quality and results have been variable. Results obtained from high quality trials indicate that the effect of chitosan on body weight is minimal and unlikely to be of clinical significance.

Effect of chitosan on weight loss in overweight and obese individuals: a systematic review of randomized controlled trials

This article aims to determine whether chitosan, a popular, over-the-counter, weight loss supplement, is an effective treatment for overweight and obesity. It is designed as a systematic review of randomized controlled trials. The data sources include the electronic databases Medline, EMBASE, Biosis, CINAHL and Cochrane Central Register of Controlled Trials (CCTR); the specialized websites Controlled Trials, International Bibliographic Information on Dietary Supplements (IBIDS), System for Information on Grey Literature in Europe (SIGLE), Reuter's Health Service, Natural Alternatives International and Pharmanutrients; and bibliographies of relevant journal articles. Included were randomized controlled trials of chitosan with a minimum duration of 4 weeks in adults who were overweight or obese and/or had hypercholesterolaemia at baseline. Fourteen trials involving a total of 1071 participants were included in the review. Analyses involving all trials indicated that chitosan preparations result in a small but statistically significant greater reduction in body weight (weighted mean difference -1.7 kg; 95% confidence interval -2.1, -1.3 kg, P < 0.00001) compared with placebo. Analyses restricted to high-quality studies showed that reductions in weight [-0.6 (-1.2, 0.1) kg, P = 0.11] were less than in lower quality studies [-2.3 (-2.7, -1.8) kg, P < 0.00001]. Results obtained from high-quality trials indicate that the effect of chitosan on body weight is minimal and unlikely to be of clinical significance.

The effect of the dietary supplement, Chitosan, on body weight: a randomised controlled trial in 250 overweight and obese adults

CONTEXT

Chitosan, a deacetylated chitin, is a widely available dietary supplement purported to decrease body weight and serum lipids through gastrointestinal fat binding. Although evaluated in a number of trials, its efficacy remains in dispute.

OBJECTIVE

To evaluate the efficacy of chitosan for weight loss in overweight and obese adults.

DESIGN AND SETTING

A 24-week randomised, double-blind, placebo-controlled trial, conducted at the University of Auckland between November 2001 and December 2002.

PARTICIPANTS

A total of 250 participants (82% women; mean (s.d.) body mass index, 35.5 (5.1) kg/m(2); mean age, 48 (12) y)

INTERVENTIONS

Participants were randomly assigned to receive 3 g chitosan/day (n=125) or placebo (n=125). All participants received standardised dietary and lifestyle advice for weight loss. Adherence was monitored by capsule counts.

MAIN OUTCOME MEASURES

The primary outcome measure was change in body weight. Secondary outcomes included changes in body mass index, waist circumference, body fat percentage, blood pressure, serum lipids, plasma glucose, fat-soluble vitamins, faecal fat, and health-related quality of life.

RESULTS

In an intention-to-treat analysis with the last observation carried forward, the chitosan group lost more body weight than the placebo group (mean (s.e.), -0.4 (0.2) kg (0.4% loss) vs +0.2 (0.2) kg (0.2% gain), P=0.03) during the 24-week intervention, but effects were small. Similar small changes occurred in circulating total and LDL cholesterol, and glucose (P<0.01). There were no significant differences between groups for any of the other measured outcomes.

CONCLUSION

In this 24-week trial, chitosan treatment did not result in a clinically significant loss of body weight compared with placebo.

Body mass index and cardiovascular disease in the Asia-Pacific Region: an overview of 33 cohorts involving 310 000 participants

BACKGROUND

Few prospective data from the Asia-Pacific region are available relating body mass index (BMI) to the risks of stroke and ischaemic heart disease (IHD). Our objective was to assess the age-, sex-, and region-specific associations of BMI with cardiovascular disease using individual participant data from prospective studies in the Asia-Pacific region.

METHODS

Studies were identified from literature searches, proceedings of meetings, and personal communication. All studies had at least 5000 person-years of follow-up. Hazard ratios were calculated from Cox models, stratified by sex and cohort, and adjusted for age at risk and smoking. The first 3 years of follow-up were excluded in order to reduce confounding due to disease at baseline.

RESULTS

A total of 33 cohort studies, including 310 283 participants, contributed 2 148 354 person-years of follow-up, during which 3332 stroke and 2073 IHD events were observed. There were continuous positive associations between baseline BMI and the risks of ischaemic stroke, haemorrhagic stroke, and IHD, with each 2 kg/m(2) lower BMI associated a 12% (95% CI: 9, 15%) lower risk of ischaemic stroke, 8% (95% CI: 4, 12%) lower risk in haemorrhagic stroke, and 11% (95% CI: 9, 13%) lower risk of IHD. The strengths of all associations were strongly age dependent, and there was no significant difference between Asian and Australasian cohorts.

CONCLUSIONS

This overview provides the most reliable estimates to date of the associations between BMI and cardiovascular disease in the Asia-Pacific region, and the first direct comparisons within the region. Continuous relationships of approximately equal strength are evident in both Asian and Australasian populations. These results indicate considerable potential for cardiovascular disease reduction with population-wide lowering of BMI.

Hormonal factors and risk of aneurysmal subarachnoid hemorrhage: an international population-based, case-control study

BACKGROUND AND PURPOSE

Subarachnoid hemorrhage (SAH) is more common in women than in men, but the role of hormonal factors in its etiology remains uncertain. The aim of this study was to examine the relationship between hormonal factors and risk of SAH in women.

METHODS

This was a prospective, multicenter, population-based, case-control study performed in 4 major urban centers in Australia and New Zealand. Two hundred sixty-eight female cases of first-ever aneurysmal SAH occurred during 1995-1998. Controls were 286 frequency-matched women from the general population of each center. Outcome measures included risk of SAH associated with use of oral contraceptive pills (OCPs), hormone replacement therapy (HRT), and various endogenous hormonal factors including menstrual patterns, parity, age at birth of first child, and breast-feeding practices.

RESULTS

Cases and controls did not differ with regard to menstrual and reproductive history except in age at birth of first child, where older age was associated with reduced risk of SAH (odds ratio [OR], 0.63; 95% CI, 0.43, 0.91). Relative to never use of HRT, the adjusted OR for ever use of HRT was 0.64 (95% CI, 0.41, 0.98), which did not alter significantly after further adjustment for possible confounding factors. Borderline evidence of an inverse association was detected for past use of HRT (adjusted OR, 0.59; 95% CI, 0.30, 1.13) and current use of HRT (adjusted OR, 0.67; 95% CI, 0.40, 1.13), but there was no evidence of an association for use of OCPs (adjusted OR, 0.97; 95% CI, 0.58, 1.60).

CONCLUSIONS

The risks of SAH are lower in women whose first pregnancy is at an older age and women who have ever used HRT but not OCPs. The findings suggest an independent etiologic role for hormonal factors in the pathogenesis of aneurysmal SAH and provide support for a protective role for HRT on risk of SAH in postmenopausal women.

Randomized, placebo-controlled trial of the angiotensin-converting enzyme inhibitor, ramipril, in patients with coronary or other occlusive arterial disease. PART-2 Collaborative Research Group. Prevention of Atherosclerosis with Ramipril

OBJECTIVES

The primary objective of this study was to investigate the effects of the angiotensin-converting enzyme (ACE) inhibitor, ramipril, on carotid atherosclerosis in patients with coronary, cerebrovascular or peripheral vascular disease.

BACKGROUND

Angiotensin-converting enzyme inhibitors have been shown to reduce the risk of coronary events in various patient groups and to prevent the development of atherosclerosis in animal models. It has been hypothesized that the clinical benefits of ACE inhibitors may, therefore, be mediated by effects on atherosclerosis.

METHODS

Six hundred seventeen patients were randomized in equal proportions to ramipril (5-10 mg daily) or placebo. At baseline, two years and four years, carotid atherosclerosis was assessed by B-mode ultrasound, and left ventricular mass was assessed by M-mode echocardiography.

RESULTS

Blood pressure (BP) was reduced by a mean of 6 mm Hg systolic and 4 mm Hg diastolic in the ramipril group compared with the placebo group (p<0.001). There was no difference between groups in the changes in common carotid artery wall thickness (p = 0.58) or in carotid plaque (p = 0.93). Left ventricular mass index decreased by 3.8 g/m2 (4%) in the ramipril group compared with the placebo group (2p = 0.04).

CONCLUSIONS

The results provide no support for the hypothesis that reduced atherosclerosis is responsible for the beneficial effects of ACE inhibitors on major coronary events. It is more likely that the benefits are due to lower BP, reduced left ventricular mass or other factors such as reversal of endothelial dysfunction.

Home or hospital for stroke rehabilitation? results of a randomized controlled trial : I: health outcomes at 6 months

BACKGROUND AND PURPOSE

We wished to examine the effectiveness of an early hospital discharge and home-based rehabilitation scheme for patients with acute stroke.

METHODS

This was a randomized, controlled trial comparing early hospital discharge and home-based rehabilitation with usual inpatient rehabilitation and follow-up care. The trial was carried out in 2 affiliated teaching hospitals in Adelaide, South Australia. Participants were 86 patients with acute stroke (mean age, 75 years) who were admitted to hospital and required rehabilitation. Forty-two patients received early hospital discharge and home-based rehabilitation (median duration, 5 weeks), and 44 patients continued with conventional rehabilitation care after randomization. The primary end point was self-reported general health status (SF-36) at 6 months after randomization. A variety of secondary outcome measures were also assessed.

RESULTS

Overall, clinical outcomes for patients did not differ significantly between the groups at 6 months after randomization, but the total duration of hospital stay in the experimental group was significantly reduced (15 versus 30 days; P<0.001). Caregivers among the home-based rehabilitation group had significantly lower mental health SF-36 scores (mean difference, 7 points).

CONCLUSIONS

A policy of early hospital discharge and home-based rehabilitation for patients with stroke can reduce the use of hospital rehabilitation beds without compromising clinical patient outcomes. However, there is a potential risk of poorer mental health on the part of caregivers. The choice of this management strategy may therefore depend on convenience and costs but also on further evaluations of the impact of stroke on caregivers.

Home or hospital for stroke Rehabilitation? Results of a randomized controlled trial : II: cost minimization analysis at 6 months

BACKGROUND AND PURPOSE

The goal of the present study was to examine the resource and economic implications of an early hospital discharge and home-based rehabilitation scheme for patients with acute stroke.

METHODS

A cost minimization analysis in conjunction with a randomized controlled trial was carried out at 2 affiliated teaching hospitals in the southern metropolitan region of Adelaide, South Australia, between 1997 and 1998. Eighty-six hospitalized patients with acute stroke who required rehabilitation were randomized to receive both early hospital discharge and home-based rehabilitation, or conventional in-hospital rehabilitation and community care. Direct and indirect costs related to stroke rehabilitation were calculated, including hospital bed days, home-based intervention program, community services, and personal expenses during the 6 months after randomization.

RESULTS

The mean cost per patient was lower for patients randomized to the early hospital discharge and home-based rehabilitation ($8040) compared with those who received conventional care ($10 054). This cost saving was not statistically significant (P=0.14). However, sensitivity analyses indicated that the cost of home-based rehabilitation was consistently lower than that of conventional care except when hospital costs were assumed to be 50% less than those used in the main analysis. Multiple regression analysis demonstrated that the cost of the home-based program was significantly related to a patient's level of disability after adjustment for age, comorbidity, and the presence or absence of a caregiver.

CONCLUSIONS

The early hospital discharge and home-based rehabilitation scheme was less costly than conventional hospital care for patients with stroke. Limitation of the provision of such services to patients with mild disability is likely to be most cost effective.

1999 World Health Organization-International Society of Hypertension Guidelines for the management of hypertension. Guidelines sub-committee of the World Health Organization

The present Guidelines were prepared by the Guidelines Sub-Committee of the World Health Organization-International Society of Hypertension (WHO-ISH) Mild Hypertension Liaison Committee, the members of which are listed at the end of the text. These guidelines represent the fourth revision of the WHO-ISH Guidelines and were finalised after presentation and discussion at the 7th WHO-ISH Meeting on Hypertension, Fukuoka, Japan, 29th Sept-1st Oct, 1998. Previous versions of the Guidelines were published in Bull WHO 1993, 71:503-517 and J Hypertens 1993, 11:905-918.

The associations of diastolic blood pressure with the risk of stroke in Western and Eastern populations

This paper reviews evidence from two overviews of prospective, observational studies of the association of diastolic blood pressure (DBP) with the risk of stroke in populations from the US and Europe and populations from China and Japan. The Western overview included seven studies involving a total of 405,511 individuals. During a mean follow-up period of 11 years, 843 strokes were observed. The Eastern overview included 18 cohorts involving a total of 124,774 participants. During a mean follow-up duration of 9 years, 1,798 strokes were observed. The shape of the association between usual DBP and the risk of stroke was similar in Western and Eastern populations, but in Eastern populations the size of the association was about 50% steeper than that in Western populations. This may be due, at least in part, to cerebral haemorrhage comprising a greater proportion of total stroke in Eastern populations. This finding, together with the high stroke rates in many Eastern Asian populations, suggests that the potential benefits of blood pressure lowering may be greater in Eastern Asia.

Applying the stages-of-change model to dietary change

The transtheoretical model of behavior change ("Stages of Change") was first proposed by Prochaska and DiClemente 14 years ago. It was originally developed by observing smokers who were planning or attempting to give up smoking. It has since been applied to behaviors other than smoking, and several recently published papers have examined its application in the area of dietary change. The complexity of dietary change, however, has made it more difficult to apply the model in this area. Studies applying the model to diet have differed in terms of the aspect of diet being examined, as well as the staging algorithms and dietary assessment methodology used. Such differences in methodology have led to variable results and have made it difficult to interpret results obtained. This review summarizes the studies in this area and makes recommendations for future research.