Excluding whole grain-containing foods from the Nova ultraprocessed food category: a cross-sectional analysis of the impact on associations with cardiometabolic risk measures

BACKGROUND

Whole grain (WG) consumption is linked with a reduced risk of chronic disease. However, the recommendations of the Nova classification system tend to contradict this evidence as high WG-containing foods, such as bread and cereals, are considered ultraprocessed, and intake is discouraged.

OBJECTIVES

This study aimed to explore associations of cardiometabolic risk measures with ultraprocessed food (UPF) intake as classified by Nova compared with when foods with ≥25% and ≥50% WG are removed from the Nova UPF category.

METHODS

A cross-sectional analysis of the 2015-18 National Health and Nutrition Examination Survey. Nova was used to identify UPFs, and the WG Initiative's definition of a WG food and front-of-pack labeling requirements was used to identify high WG foods. Regression models were used to explore impacts on the association of UPF intake (quintiles) and cardiometabolic risk measures when high WG foods were excluded from the Nova UPF category.

RESULTS

Participants in the highest quintile of UPF intake had significantly higher weight [83.6 kg (0.8)], BMI (in kg/m2) [30.6 (0.3)], waist circumference [103.1 cm (0.6)], and weight-to-height ratio [0.63 (0.003)] compared to those in the lowest quintile (P < 0.0001 for all). The same was found when foods with ≥25% and ≥50% WG were removed. Positive associations for C-reactive protein were found when ≥25% and ≥50% WG-containing foods were removed only [2.32 mg/L (0.1), P = 0.0209; 2.37 mg/L (0.1), P = 0.0179, respectively]. Participants in the highest quintile had significantly lower total cholesterol after adjustment when foods with ≥50% WG were removed [4.98 mmol/L (0.04), P = 0.0292]. Adjusted R2 values remained relatively unchanged across each approach for all outcomes.

CONCLUSIONS

Foods high in WG may not significantly contribute to the deleterious associations previously observed between UPF intake and cardiometabolic risk factors. Consideration of their contribution to healthful dietary patterns and diet quality in the United States population should be made prior to the endorsement of Nova.

Translation of Two Healthy Eating and Active Living Support Programs for Parents of 2-6-Year-Old Children: Outcomes of the 'Time for Healthy Habits' Parallel Partially Randomised Preference Trial

This translation study assessed the effectiveness of two remotely delivered healthy eating and active living interventions for parents of 2- to 6-year-old children in improving child fruit and vegetable intake, non-core food intake, body mass index (BMI), physical activity, screen time, and sleep. Parents (n = 458) were recruited to a partially randomised preference trial comprising three intervention groups. Healthy Habits Plus comprised six telephone calls, Time2bHealthy comprised six online modules, and the active control comprised ten information sheets and a summary booklet. Data were collected from parents via a telephone questionnaire at baseline and nine months post-baseline. Data were analysed for randomised participants alone (n = 240), preference participants alone (n = 218), and all participants combined (n = 458). There was no significant improvement in fruit and vegetable intake (primary outcome) when comparing the telephone and online interventions to the control. In both the randomised only and all participants combined analyses, there was a significant improvement in non-core food intake for the telephone intervention compared to the control (p < 0.001). Differences between interventions for other outcomes were small. In conclusion, the telephone and online interventions did not improve child fruit and vegetable intake relative to written materials, but the telephone intervention did improve non-core food intake.

Statistical methods and software used in nutrition and dietetics research: A review of the published literature using text mining

AIM

Dietitians must be statistically literate to effectively interpret the scientific literature underpinning the discipline. Despite this, no study has been conducted that objectively identifies common statistical methods and packages specific to current nutrition and dietetics literature. This study aimed to identify statistical methods and software frequently used in nutrition and dietetics research.

METHODS

A text mining approach using the bag-of-words method was applied to a random sample of articles obtained from all journals in the 'Nutrition and Dietetics' subject category within the SCImago Journal and Country Rank portal and published in 2018. A list of 229 statistical terms and 19 statistical software packages was developed to define the search terms to be mined. Statistical information from the methods section of included articles was extracted into Microsoft Excel (2016) for data cleaning. Statistical analyses were conducted in R (Version 3.6.0) and Microsoft Excel (2016).

RESULTS

Seven hundred and fifty-seven journal articles were included. Numerical descriptive statistics were the most common statistical method group, appearing in 83.2% of articles (n = 630). This was followed by specific hypothesis tests (68.8%, n = 521), general hypothesis concepts (58.4%, n = 442), regression (44.4%, n = 336), and ANOVA (30.8%, n = 233). IBM SPSS statistics was the most common statistical software package, reported in 41.7% of included articles.

CONCLUSION

These findings provide useful information for educators to evaluate current statistics curricula and develop short courses for continuing education. They may also act as a starting point for dietitians to educate themselves on typical statistical methods they may encounter.

Can Parental Engagement in Social Media Enhance Outcomes of an Online Healthy Lifestyle Program for Preschool-Aged Children?

This study explored parental engagement, child BMI and secondary outcomes from the social media component of an online healthy lifestyle program for parents of preschool-aged children. Intervention group participants received access to an online program and Facebook group. Data were collected at baseline and 3- and 6-months follow-up. Facebook usage data on comments and posts were used to determine total active engagement. There was a high level of Facebook group membership and most parents actively engaged at least once. Although there were varying levels of engagement between modules and cohorts, it was modest overall. User acceptability of the Facebook group was lower than expected. Children of parents in the intervention who engaged more in the Facebook group (by posting and commenting) demonstrated greater sleep duration over time (estimate 1.79, 95% CI 0.42 to 3.17, p = .01) Children of parents who engaged more in the Facebook group also participated in less moderate- to vigorous-intensity physical activity (estimate -0.14, 95% CI -0.26 to -0.01, p = .03). This study is one of the first parent-focussed healthy lifestyle interventions to include a social media component. Further research is recommended with larger sample sizes and longer duration to further explore the potential of social media in childhood obesity interventions.

Correction to: Effectiveness of quality incentive payments in general practice (EQuIP-GP): a study protocol for a cluster-randomised trial of an outcomes-based funding model in Australian general practice to improve patient care

In the original publication of this article [1], the first name of the 3rd author is wrong.

Effectiveness of quality incentive payments in general practice (EQuIP-GP): a study protocol for a cluster-randomised trial of an outcomes-based funding model in Australian general practice to improve patient care

BACKGROUND

There is international interest in whether improved primary care, in particular for patients with chronic or complex conditions, can lead to decreased use of health resources and whether financial incentives help achieve this goal. This trial (EQuIP-GP) will investigate whether a funding model based upon targeted, continuous quality incentive payments for Australian general practices increases relational continuity of care, and lessens health-service utilisation, for high-risk patients and children.

METHODS

We will use a mixed methods approach incorporating a two-arm pragmatic cluster randomised control trial with nested qualitative case studies. We aim to recruit 36 general practices from Practice-Based Research Networks (PBRN) covering urban and regional areas of Australia, randomised into intervention and control groups. Control practices will provide usual care while intervention practices will be supported to implement a new service model incorporating incentives for relational continuity and timely access to appointments. Patients will comprise three groups: older (over 65 years); 18-65 years with chronic and/or complex conditions; and those aged less than 16 years with increased risk of hospitalisation. The funding model includes financial incentives to general practitioners (GPs) for providing longer consultations, same day access and timely follow-up after hospitalisation to enrolled patients. The payments are proportional to expected health system savings associated with improved quality of GP care. An outreach facilitator will work with practices to help incorporate the incentive model into usual work. The main outcome measure is relational continuity of care (Primary Care Assessment Tool short-form survey), with secondary outcomes including health-related quality of life and health service use (hospitalisations, emergency presentations, GP and specialist services in the community, medicine prescriptions and targeted pathology and imaging ordering). Outcomes will be initially evaluated over a period of 12 months, with ongoing data collection for 5 years.

DISCUSSION

The trial will provide robust evidence on a novel approach to providing continuous incentives for improving quality of general practice care, which can be compared to block payment incentives awarded at target quality levels of pay-for-performance, both within Australia and also internationally.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12618000105246. Registered on 23 January 2018.

An Internet-Based Childhood Obesity Prevention Program (Time2bHealthy) for Parents of Preschool-Aged Children: Randomized Controlled Trial

Background

Electronic health (eHealth) obesity programs offer benefits to traditionally delivered programs and have shown promise in improving obesity-related behaviors in children.

Objective

This study aimed to assess the efficacy of a parent-focused, internet-based healthy lifestyle program for preschool-aged children, who are overweight or at or above the fiftieth percentile for body mass index (BMI) for their age and sex, on child BMI, obesity-related behaviors, parent modeling, and parent self-efficacy.

Methods

The Time2bHealthy randomized controlled trial was conducted in Australia, during 2016 to 2017. Participants were recruited both online and through more traditional means within the community. Parent or carer, and child (aged 2-5 years) dyads were randomized into an intervention or comparison group. Intervention participants received an 11-week internet-based healthy lifestyle program, underpinned by social cognitive theory, followed by fortnightly emails for 3 months thereafter. Intervention participants set goals and received individual feedback from a dietitian. They were also encouraged to access and contribute to a closed Facebook group to communicate with other participants and the dietitian. Comparison participants received email communication only. Objectively measured child BMI was the primary outcome. Secondary outcomes included objectively measured physical activity, parent-measured and objectively measured sleep habits, and parent-reported dietary intake, screen time, child feeding, parent modeling, and parent self-efficacy. All data were collected at face-to-face appointments at baseline, 3 months, and 6 months by blinded data collectors. Randomization was conducted using a computerized random number generator post baseline data collection.

Results

A total of 86 dyads were recruited, with 42 randomized to the intervention group and 44 to the comparison group. Moreover, 78 dyads attended the 3- and 6-month follow-ups, with 7 lost to follow-up and 1 withdrawing. Mean child age was 3.46 years and 91% (78/86) were in the healthy weight range. Overall, 69% (29/42) of participants completed at least 5 of the 6 modules. Intention-to-treat analyses found no significant outcomes for change in BMI between groups. Compared with children in the comparison group, those in the intervention group showed a reduced frequency of discretionary food intake (estimate −1.36, 95% CI −2.27 to −0.45; P=.004), and parents showed improvement in child feeding pressure to eat practices (−0.30, 95% CI 0.06 to −0.00; P=.048) and nutrition self-efficacy (0.43, 95% CI 0.10 to 0.76; P=.01). No significant time by group interaction was found for other outcomes.

Conclusions

The trial demonstrated that a parent-focused eHealth childhood obesity prevention program can provide support to improve dietary-related practices and self-efficacy but was not successful in reducing BMI. The target sample size was not achieved, which would have affected statistical power.

Trial Registration

Australian New Zealand Clinical Trials Registry ANZCTR12616000119493; https://www.anzctr.org.au/ Trial/Registration/TrialReview.aspx?id=370030 (Archived by WebCite at http://www.webcitation.org/74Se4S7ZZ).

Wrist Acceleration Cut Points for Moderate-to-Vigorous Physical Activity in Youth

PURPOSE

This study aimed to examine the validity of wrist acceleration cut points for classifying moderate (MPA), vigorous (VPA), and moderate-to-vigorous (MVPA) physical activity.

METHODS

Fifty-seven children (5-12 yr) completed 15 semistructured activities. Three sets of wrist cut points (>192 mg, >250 mg, and >314 mg), previously developed using Euclidian norm minus one (ENMO192+), GENEActiv software (GENEA250+), and band-pass filter followed by Euclidian norm (BFEN314+), were evaluated against indirect calorimetry. Analyses included classification accuracy, equivalence testing, and Bland-Altman procedures.

RESULTS

All cut points classified MPA, VPA, and MVPA with substantial accuracy (ENMO192+: κ = 0.72 [95% confidence interval = 0.72-0.73], MVPA: area under the receiver operating characteristic curve (ROC-AUC) = 0.85 [0.85-0.86]; GENEA250+: κ = 0.75 [0.74-0.76], MVPA: ROC-AUC = 0.85 [0.85-0.86]; BFEN314+: κ = 0.73 [0.72-0.74], MVPA: ROC-AUC = 0.86 [0.86-0.87]). BFEN314+ misclassified 19.7% non-MVPA epochs as MPA, whereas ENMO192+ and GENEA250+ misclassified 32.6% and 26.5% of MPA epochs as non-MVPA, respectively. Group estimates of MPA time were equivalent (P < 0.01) to indirect calorimetry for the BFEN314+ MPA cut point (mean bias = -1.5%, limits of agreement [LoA] = -57.5% to 60.6%), whereas estimates of MVPA time were equivalent (P < 0.01) to indirect calorimetry for the ENMO192+ (mean bias = -1.1%, LoA = -53.7% to 55.9%) and GENEA250+ (mean bias = 2.2%, LoA = -56.5% to 52.2%) cut points. Individual variability (LoA) was large for MPA (min: BFEN314+, -60.6% to 57.5%; max: GENEA250+, -42.0% to 104.1%), VPA (min: BFEN314+, -238.9% to 54.6%; max: ENMO192+, -244.5% to 127.4%), and MVPA (min: ENMO192+, -53.7% to 55.0%; max: BFEN314+, -83.9% to 25.3%).

CONCLUSION

Wrist acceleration cut points misclassified a considerable proportion of non-MVPA and MVPA. Group-level estimates of MVPA were acceptable; however, error for individual-level prediction was larger.

Outcomes of multisite antimicrobial stewardship programme implementation with a shared clinical decision support system

Background

Studies evaluating antimicrobial stewardship programmes (ASPs) supported by computerized clinical decision support systems (CDSSs) have predominantly been conducted in single site metropolitan hospitals.

Objectives

To examine outcomes of multisite ASP implementation supported by a centrally deployed CDSS.

Methods

An interrupted time series study was conducted across five hospitals in New South Wales, Australia, from 2010 to 2014. Outcomes analysed were: effect of the intervention on targeted antimicrobial use, antimicrobial costs and healthcare-associated Clostridium difficile infection (HCA-CDI) rates. Infection-related length of stay (LOS) and standardized mortality ratios (SMRs) were also assessed.

Results

Post-intervention, antimicrobials targeted for increased use rose from 223 to 293 defined daily doses (DDDs)/1000 occupied bed days (OBDs)/month (+32%, P  <   0.01). Conversely, antimicrobials targeted for decreased use fell from 254 to 196 DDDs/1000 OBDs/month (-23%; P  <   0.01). These effects diminished over time. Antimicrobial costs decreased initially (-AUD$64551/month; P  <   0.01), then increased (+AUD$7273/month; P  <   0.01). HCA-CDI rates decreased post-intervention (-0.2 cases/10 000 OBDs/month; P  <   0.01). Proportional LOS reductions for key infections (respiratory from 4.8 to 4.3 days, P  <   0.01; septicaemia 6.8 to 6.1 days, P  <   0.01) were similar to background LOS reductions (2.1 to 1.9 days). Similarly, infection-related SMRs (observed/expected deaths) decreased (respiratory from 1.1 to 0.75; septicaemia 1.25 to 0.8; background rate 1.19 to 0.90.

Conclusions

Implementation of a collaborative multisite ASP supported by a centrally deployed CDSS was associated with changes in targeted antimicrobial use, decreased antimicrobial costs, decreased HCA-CDI rates, and no observable increase in LOS or mortality. Ongoing targeted interventions are suggested to promote sustainability.

The effect of nut consumption on markers of inflammation and endothelial function: a systematic review and meta-analysis of randomised controlled trials

OBJECTIVES

To examine the effect of nut consumption on inflammatory biomarkers and endothelial function.

DESIGN

A systematic review and meta-analysis.

DATA SOURCES

MEDLINE, PubMed, Cumulative Index to Nursing and Allied Health Literature and Cochrane Central Register of Controlled Trials (all years to 13 January 2017).

ELIGIBILITY CRITERIA

Randomised controlled trials (with a duration of 3 weeks or more) or prospective cohort designs conducted in adults; studies assessing the effect of consumption of tree nuts or peanuts on C-reactive protein (CRP), adiponectin, tumour necrosis factor alpha, interleukin-6, intercellular adhesion molecule 1, vascular cell adhesion protein 1 and flow-mediated dilation (FMD).

DATA EXTRACTION AND ANALYSIS

Relevant data were extracted for summary tables and analyses by two independent researchers. Random effects meta-analyses were conducted to explore weighted mean differences (WMD) in change or final mean values for each outcome.

RESULTS

A total of 32 studies (all randomised controlled trials) were included in the review. The effect of nut consumption on FMD was explored in nine strata from eight studies (involving 652 participants), with consumption of nuts resulting in significant improvements in FMD (WMD: 0.79%(95% CI 0.35 to 1.23)). Nut consumption resulted in small, non-significant differences in CRP (WMD: -0.01 mg/L (95% CI -0.06 to 0.03)) (26 strata from 25 studies), although sensitivity analyses suggest results for CRP may have been influenced by two individual studies. Small, non-significant differences were also found for other biomarkers of inflammation.

CONCLUSIONS

This systematic review and meta-analysis of the effects of nut consumption on inflammation and endothelial function found evidence for favourable effects on FMD, a measure of endothelial function. Non-significant changes in other biomarkers indicate a lack of consistent evidence for effects of nut consumption on inflammation. The findings of this analysis suggest a need for more research in this area, with a particular focus on randomised controlled trials.

PROSPERO REGISTRATION NUMBER

CRD42016045424.

Wrist Accelerometer Cut Points for Classifying Sedentary Behavior in Children

INTRODUCTION

This study aimed to examine the validity and accuracy of wrist accelerometers for classifying sedentary behavior (SB) in children.

METHODS

Fifty-seven children (5-8 and 9-12 yr) completed an ~170-min protocol, including 15 semistructured activities and transitions. Nine ActiGraph (GT3X+) and two GENEActiv wrist cut points were evaluated. Direct observation was the criterion measure. The accuracy of wrist cut points was compared with that achieved by the ActiGraph hip cut point (≤25 counts per 15 s) and the thigh-mounted activPAL3. Analyses included equivalence testing, Bland-Altman procedures, and area under the receiver operating curve (ROC-AUC).

RESULTS

The most accurate ActiGraph wrist cut points (Kim; vector magnitude, ≤3958 counts per 60 s; vertical axis, ≤1756 counts per 60 s) demonstrated good classification accuracy (ROC-AUC = 0.85-0.86) and accurately estimated SB time in 5-8 yr (equivalence P = 0.02; mean bias = 4.1%, limits of agreement = -20.1% to 28.4%) and 9-12 yr (equivalence P < 0.01; -2.5%, -27.9% to 22.9%). The mean bias of SB time estimates from Kim were smaller than ActiGraph hip (5-8 yr: 15.8%, -5.7% to 37.2%; 9-12 yr: 17.8%, -3.9% to 39.5%) and similar to or smaller than activPAL3 (5-8 yr: 12.6%, -39.8% to 14.7%; 9-12 yr: -1.4%, -13.9% to 11.0%), although classification accuracy was similar to ActiGraph hip (ROC-AUC = 0.85) but lower than activPAL3 (ROC-AUC = 0.92-0.97). Mean bias (5-8 yr: 6.5%, -16.1% to 29.1%; 9-12 yr: 10.5%, -13.6% to 34.6%) for the most accurate GENEActiv wrist cut point (Schaefer: ≤0.19 g) was smaller than ActiGraph hip, and activPAL3 in 5-8 yr, but larger than activPAL3 in 9-12 yr. However, SB time estimates from Schaefer were not equivalent to direct observation (equivalence P > 0.05) and classification accuracy (ROC-AUC = 0.79-0.80) was lower than for ActiGraph hip and activPAL3.

CONCLUSION

The most accurate SB ActiGraph (Kim) and GENEActiv (Schaefer) wrist cut points can be applied in children with similar confidence as the ActiGraph hip cut point (≤25 counts per 15 s), although activPAL3 was generally more accurate.

Effect of interdisciplinary care on weight loss: a randomised controlled trial

OBJECTIVE

To determine the effectiveness of a novel interdisciplinary treatment compared with usual care on weight loss in overweight and obese adult volunteers.

DESIGN

Single blinded controlled trial. Participants randomly assigned to usual care (C, general guideline-based diet and exercise advice), intervention (I, interdisciplinary protocol) or intervention + a healthy food supplement (30 g walnuts/day) (IW).

SETTING

Community based study, Illawarra region, south of Sydney, Australia.

PARTICIPANTS

Generally well volunteer adult residents, 25-54 years, body mass index (BMI) 25-40kg/m² were eligible. At baseline 439 were assessed, 377 were randomised, 298 completed the 3-month intensive phase and 178 completed the 12-month follow-up.

INTERVENTIONS

Treatment was provided at clinic visits intensively (0 months, 1 month, 2 months, 3 months) then quarterly to 12 months. Support phone calls were quarterly. All participants underwent blinded assessments for diet, exercise and psychological status.

PRIMARY AND SECONDARY MEASURES

The primary outcome was difference in weight loss between baseline and 12 months (clinically relevant target 5% loss). Secondary outcomes were changes in blood pressure, fasting blood glucose and lipids, and changes in diet, exercise and psychological parameters.

RESULTS

At 12 months, differences in weight loss were identified (p<0.001). The I group lost more than controls at 3 months (91.11 (92.23,90.00), p<0.05) and the IW more than controls at 3 months (91.25 (92.35,90.15), p<0.05) and 6 months (92.20 (93.90,90.49), p<0.01). The proportion achieving 5% weight loss was significantly different at 3 months, 6 months and 9 months (p=0.04, p=0.03, p=0.03), due to fewer controls on target at 3 months, 6 months and 9 months and more IW participants at 6 months. Reductions in secondary outcomes (systolic blood pressure, blood glucose/lipid parameters and lifestyle measures) followed the pattern of weight loss.

CONCLUSIONS

An interdisciplinary intervention produced greater and more clinically significant and sustained weight loss compared with usual care. The intensive phase was sufficient to reach clinically relevant targets, but long-term management plans may be required.

TRIAL REGISTRATION NUMBER

ANZCTRN 12614000581662; Post-results.

Impact of providing walnut samples in a lifestyle intervention for weight loss: a secondary analysis of the HealthTrack trial

Background: Being more specific about individual food choices may be advantageous for weight loss. Including a healthy food (e.g. walnuts) may help to expose effects.

Objective: To examine the impact of including walnuts in diets for weight loss.

Design: Secondary analysis of the HealthTrack lifestyle intervention trial. Overweight and obese participants were randomized to: usual care (C), interdisciplinary intervention including individualized dietary advice (I), or interdisciplinary intervention including 30 g walnuts/day (IW). Changes in body weight, energy intake, intake of key foods, physical activity, and mental health over three and 12 months were explored.

Results: A total of 293 participants completed the intensive three-month study period, and 175 had data available at 12 months. The IW group achieved the greatest weight loss at three months. IW reported significant improvements in healthy food choices, and decreased intakes of discretionary foods/beverages, compared to C. Weight loss remained greatest in IW at 12 months.

Discussion: Significant effects were seen after three months, with the IW group achieving greater weight loss and more favorable changes in food choices.

Conclusions: Including 30 grams walnuts/day in an individualized diet produced weight loss and positive changes in food choice.

Associations between Dietary Patterns and Blood Pressure in a Clinical Sample of Overweight Adults

BACKGROUND

Dietary pattern analysis provides important evidence revealing diet-disease relationships. It may be especially useful in areas less well researched, such as diet and hypertension in clinical populations.

OBJECTIVE

The aim of this study was to identify the association between dietary patterns and blood pressure (BP) in a sample of overweight adults volunteering for a clinical trial for weight loss.

DESIGN

This cross-sectional analysis used baseline data from the HealthTrack study, a 12-month randomized controlled trial. Dietary intake was evaluated with 4-day food records.

PARTICIPANTS/SETTING

Participants were 328 adults recruited from the Illawarra region of New South Wales, Australia, between May 2014 and April 2015.

MAIN OUTCOME MEASURES

Resting BP and 24-hour urine sodium and potassium were measured.

STATISTICAL ANALYSIS

Dietary patterns were derived by principal component analysis from 21 food groups. Multiple regression analysis was performed to assess the association between the extracted dietary patterns and BP.

RESULTS

The participants' mean age was 43.6±8.0 years, mean body mass index was 32.4±4.2, and mean systolic BP/diastolic BP was 124.9±14.5/73.3±9.9 mm Hg. Six major dietary patterns were identified: "nuts, seeds, fruit, and fish," "milk and meat," "breads, cereals, and snacks," "cereal-based products, fats, and oils," "alcohol, eggs, and legumes," and "savoury sauces, condiments, and meat." The "nuts, seeds, fruit, and fish" dietary pattern was significantly and inversely associated with systolic BP (F [7,320]=15.248; P<0.0005; adjusted R²=0.234 and diastolic BP (F [7,320]=17.351; P<0.0005; adjusted R²=0.259) and sodium-to-potassium ratio (F [7,320]=6.210; P<0.0005; adjusted R²=0.100).

CONCLUSIONS

A dietary pattern rich in nuts, seeds, fruit, and fish was inversely associated with blood pressure in this clinical sample. The findings suggest that current dietary guidelines are relevant to an overweight clinical population and support the value of dietary pattern analysis when exploring the diet-disease relationship.

Validation of thigh-based accelerometer estimates of postural allocation in 5-12 year-olds

OBJECTIVES

To validate activPAL3™ (AP3) for classifying postural allocation, estimating time spent in postures and examining the number of breaks in sedentary behaviour (SB) in 5-12 year-olds.

DESIGN

Laboratory-based validation study.

METHODS

Fifty-seven children completed 15 sedentary, light- and moderate-to-vigorous intensity activities. Direct observation (DO) was used as the criterion measure. The accuracy of AP3 was examined using a confusion matrix, equivalence testing, Bland-Altman procedures and a paired t-test for 5-8y and 9-12y.

RESULTS

Sensitivity of AP3 was 86.8%, 82.5% and 85.3% for sitting/lying, standing, and stepping, respectively, in 5-8y and 95.3%, 81.5% and 85.1%, respectively, in 9-12y. Time estimates of AP3 were equivalent to DO for sitting/lying in 9-12y and stepping in all ages, but not for sitting/lying in 5-12y and standing in all ages. Underestimation of sitting/lying time was smaller in 9-12y (1.4%, limits of agreement [LoA]: -13.8 to 11.1%) compared to 5-8y (12.6%, LoA: -39.8 to 14.7%). Underestimation for stepping time was small (5-8y: 6.5%, LoA: -18.3 to 5.3%; 9-12y: 7.6%, LoA: -16.8 to 1.6%). Considerable overestimation was found for standing (5-8y: 36.8%, LoA: -16.3 to 89.8%; 9-12y: 19.3%, LoA: -1.6 to 36.9%). SB breaks were significantly overestimated (5-8y: 53.2%, 9-12y: 28.3%, p<0.001).

CONCLUSIONS

AP3 showed acceptable accuracy for classifying postures, however estimates of time spent standing were consistently overestimated and individual error was considerable. Estimates of sitting/lying were more accurate for 9-12y. Stepping time was accurately estimated for all ages. SB breaks were significantly overestimated, although the absolute difference was larger in 5-8y. Surveillance applications of AP3 would be acceptable, however, individual level applications might be less accurate.

Relationship between sodium and potassium intake and blood pressure in a sample of overweight adults

OBJECTIVE

The aim of this study was to examine the relationship between sodium and potassium intakes and blood pressure (BP) in a clinical sample.

METHODS

Secondary analysis of baseline data from 328 participants (mean age: 43.6 ± 8 y, mean body mass index [BMI]: 32.4 ± 4.2 kg/m², mean systolic BP [SBP]/diastolic BP [DBP]: 124.9 ± 14.5/73.3 ± 9.9 mm Hg) of the 12-mo HealthTrack randomized controlled weight loss trial was conducted. Resting BP and 24-h urine sodium and potassium were measured. Dietary intake was evaluated with 4-d food records and self-reported diet histories.

RESULTS

Urinary sodium was positively correlated (Spearman's rho) with SBP (r = 0.176; P = 0.001) and DBP (r = 0.150; P = 0.003). The ratio of sodium to potassium was positively correlated with SBP (r = 0.1; P = 0.035). Urinary sodium (F [4,323] = 20.381; P < 0.0005; adjusted R² = 0.231) and sodium-to-potassium ratio (F[4,323] = 25.008; P < 0.0005; adjusted R² = 0.227) significantly predicted SBP after controlling for age, sex, BMI, and hypertension medication use. Dietary sodium and potassium significantly predicted urinary sodium (B = 0.33, t = 4.032, P < 0.01) and potassium (B = 0.67, t = 8.537, P < 0.01) excretion, respectively, after adjustment for energy and BMI. Median dietary sodium intake was 3197 mg/d and median dietary potassium intake was 2886 mg/d. Cereal-based products and dishes were the major contributors (22%) to total sodium intake.

CONCLUSIONS

In the present study, a high dietary sodium intake and high sodium-to-potassium ratio predicted high SBP. This suggests a need to focus dietary advice on reduction of sources of sodium and increasing sources of potassium in weight loss interventions to improve BP control.

Validation of the SenseWear Mini activity monitor in 5-12-year-old children

OBJECTIVES

This study aimed to validate SenseWear Mini software algorithm versions 2.2 (SW2.2) and 5.2 (SW5.2) for estimating energy expenditure (EE) in children.

DESIGN

Laboratory-based validation study.

METHODS

57 children aged 5-12 y completed a protocol involving 15 semi-structured sedentary (SED), light-intensity (LPA), and moderate- to vigorous-intensity (MVPA) physical activities. EE was estimated using portable indirect calorimetry (IC). The accuracy of EE estimates (kcal·min^-1) from SW2.2 and SW5.2 were examined at the group level and individual level using the mean absolute percentage error (MAPE), Bland-Altman plots and equivalence testing.

RESULTS

MAPE values were lower for SW5.2 (30.1±10.7%) than for SW2.2 (44.0±6.2%). Although mean differences for SW5.2 were smaller than for SW2.2 during SED (-0.23±0.22 vs. -0.61±0.20kcal·min^-1), LPA (-0.69±0.76 vs. -1.07±0.46kcal·min^-1) and MVPA (-2.22±1.15 vs. -2.57±1.15kcal·min^-1), limits of agreement did not decrease for the updated algorithms. For all activities, SW2.2 and SW5.2 were not equivalent to IC (p>0.05). Errors increased with increasing intensity.

CONCLUSION

The current SenseWear Mini algorithms SW5.2 underestimated EE. The overall improved accuracy for SW5.2 was not accompanied with improved accuracy at the individual level and EE estimates were not equivalent to IC.

Socioeconomic disadvantage and its implications for population health planning of obesity and overweight, using cross-sectional data from general practices from a regional catchment in Australia

OBJECTIVES

To identify smaller geographic and region-specific evidence to inform population health planning for overweight and obesity.

DESIGN

Cross-sectional secondary analysis of data.

SETTING

Primary healthcare-17 general practices located in the Illawarra-Shoalhaven region of New South Wales (NSW).

PARTICIPANTS

A subset (n=36 674) of the Sentinel Practices Data Sourcing project adult persons data set (n=118 794) that included information on disease status of all adult patients who had height and weight measurements recorded in their electronic health records and had visited the included general practices within the Illawarra-Shoalhaven region of NSW between September 2011 and September 2013.

MAIN OUTCOME MEASURES

Age-adjusted odds ratio (aOR) of overweight and obesity was determined for high and low levels of socioeconomic disadvantage based on Socio-Economic Indexes for Areas (SEIFA)-Index of Relative Socio-Economic Disadvantage (IRSD) scores of patients' residential statistical local area.

RESULTS

In men, overweight was lowest in areas of highest socioeconomic disadvantage (aOR=0.910; 95% CI 0.830 to 0.998; p<0.001); but no statistically significant association with socioeconomic score was found for women. Overall obesity was associated with high socioeconomic disadvantage (aOR=1.292; 95% CI 1.210 to 1.379; p<0.001).

CONCLUSIONS

This type of data analysis reveals multiple layers of evidence that should be assessed for population health approaches to curb the epidemic of obesity and overweight. It strongly highlights the need for preventive health initiatives to be specific to gender and socioeconomic attributes of the target population.

Dietary Patterns and Blood Pressure in Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Hypertension is a major risk factor for developing cardiovascular disease, stroke, and kidney disease. To lower blood pressure (BP), several lifestyle changes are recommended such as weight loss, exercise, and following a healthy diet. Investigating the effect of single nutrients may have positive results, but food is consumed as part of a whole diet, resulting in nutrient interactions. The aim of this systematic review and meta-analysis was to assess the effect of dietary patterns on BP in adults. Studies that were published between January 1999 and June 2014 were retrieved using Scopus, Web of Science, and the MEDLINE database. Seventeen randomized controlled trials were included in the meta-analysis. The results suggest that healthy dietary patterns such as the Dietary Approaches to Stop Hypertension diet, Nordic diet, and Mediterranean diet significantly lowered systolic BP and diastolic BP by 4.26 mm Hg and 2.38 mm Hg, respectively. These diets are rich in fruit, vegetables, whole grains, legumes, seeds, nuts, fish, and dairy and low in meat, sweets, and alcohol. Lifestyle factors such as exercise and weight loss in combination with dietary changes may also reduce BP. Further research is needed to establish the effect of dietary patterns on BP in different cultures other than those identified in this review. The review was registered on PROSPERO (International prospective register of systematic reviews) as CRD42015016272.

Intraindividual variation in urinary iodine concentrations: effect of adjustment on population distribution using two and three repeated spot urine collections

OBJECTIVES

To determine the effect of adjustment for intraindividual variation on estimations of urinary iodine concentrations (UIC), prevalence of iodine deficiency and population distribution of iodine status.

SETTING

Community-dwelling older adults from New South Wales, Australia.

PARTICIPANTS

84 healthy men and women aged 60-95 years were recruited prior to introduction of the mandatory iodine fortification programme.

PRIMARY AND SECONDARY OUTCOME MEASURES

UIC data were collected from three spot urine samples, each 1 week apart. Repeated measures analysis of variance were determined between-person (sb) and total (sobs) SDs. Adjusted UIC values were calculated as ((person's UIC-group mean)×(sb/sobs))+group mean, and a corrected UIC distribution was calculated.

RESULTS

The sb/sobs for using three samples and two samples were 0.83 and 0.79, respectively. Following adjustment for intraindividual variation, the proportion with UIC <50 μg/L reduced from 33% to 19%, while the proportion with UIC ≥100 μg/L changed from 21% to 17%. The 95th centile for UIC decreased from 176 to 136 μg/L. Adjustment by taking averages yielded a lesser degree of contraction in the distribution than the analysis of variance method.

CONCLUSIONS

The addition of information about intraindividual variability has potential for increasing the interpretability of UIC data collected to monitor the iodine status of a population.

Foods, nutrients or whole diets: effects of targeting fish and LCn3PUFA consumption in a 12mo weight loss trial

Background

There is some evidence in the literature that emphasising fish consumption may assist with weight loss. The aim was to assess the effects of advice to consume 2 fish meals per week in a weight loss diet.

Methods

A parallel randomised placebo-controlled trial was conducted in 118 obese Australian adults (mean BMI ± SD 31.3 ± 3.5 kg/m²; mean age ± SD 45 ± 10 y; 28% male). Participants received low calorie dietary advice + placebo (1 g olive oil; Control), low calorie dietary advice emphasising fish + placebo (Fish), or low calorie dietary advice emphasising fish diet + LCn3PUFA supplements (Fish + S). Individualised advice targeted 2 MJ energy deficit (30%E fat, 45%E carbohydrate and 25%E protein) with or without two servings (180 g) fatty fish/wk.

Results

All groups lost weight at 12 months (Control −4.5 kg vs. Fish −4.3 kg vs. Fish + S −3.3 kg; p < 0.001) and percentage body fat (Control: -1.5% vs. Fish: -1.4% vs. Fish + S: -0.7%; p < 0.001) but there were no significant differences between groups. Cardiovascular disease risk factors changed as expected from weight loss.

Conclusions

Advice to consume 2 fish meals per week did not enhance the effects on weight loss of a healthy low calorie diet.

Trial registration

ACTRN12608000425392.

Addressing the deficiencies in the evidence-base for primary practice in regional Australia - sentinel practices data sourcing (SPDS) project: a pilot study

BACKGROUND

Chronic disease risk on a population level can be quantified through health surveys, either continuous or periodic. To date, information gathered from primary care interactions, using sentinel sites, has not been investigated as a potentially valuable surveillance system in Australia.

METHODS

A pilot study was conducted in a single General Practice in a regional area of New South Wales, Australia to assess the feasibility of accessing data obtained through a computerised chronic disease management program that has been designed for desktop application (Pen Computer Systems (PCS) Clinical Audit Tool: ™ PCS CAT). Collated patient data included information on chronic disease management and prevention, prevalence of overweight and obesity, mental health indicators, medication profiling and home medicine reviews, as well as uptake of preventive health services (immunisation and cervical cancer screening).

RESULTS

Higher than national average estimates were found for the age-adjusted prevalence of chronic diseases such as hypertension (14.3% for sample vs 10.4%, nationally), anxiety disorders (4.4% vs 3.8%) and obesity/overweight (67.1 vs 63.4%). Preventive health assessment items were undersubscribed, ranging from 6-20% in eligible patients.

CONCLUSIONS

This pilot study has demonstrated that the scope of data collected by patient visits to their General Practitioners, facilitated through the Medicare-funded primary health care system in Australia, offers a feasible opportunity for monitoring of chronic disease prevalence and its associated risk factors. The inclusion of a larger number of sentinel sites that are generalizable to the population being served would provide an accurate and region-specific system for the purposes of population health planning at the primary care level in order to improve the overall health of the community.

Analyzing weight loss intervention studies with missing data: which methods should be used?

OBJECTIVE

Missing data due to study dropout is common in weight loss trials and several statistical methods exist to account for it. The aim of this study was to identify methods in the literature and to compare the effects of methods of analysis using simulated data sets.

METHODS

Literature was obtained for a 1-y period to identify analytical methods used in reporting weight loss trials. A comparison of methods with large or small between-group weight loss, and missing data that was, or was not, missing randomly was conducted in simulated data sets based on previous research.

RESULTS

Twenty-seven studies, some with multiple analyses, were retrieved. Complete case analysis (n = 17), last observation carried forward (n = 6), baseline carried forward (n = 4), maximum likelihood (n = 6), and multiple imputation (n = 2) were the common methods of accounting for missing data. When comparing methods on simulated data, all demonstrated a significant effect when the between-group weight loss was large (P < 0.001, interaction term) regardless of whether the data was missing completely at random. When the weight loss interaction was small, the method used for analysis gave considerably different results with mixed models (P = 0.180) and multiple imputations (P = 0.125) closest to the full data model (P = 0.033).

CONCLUSION

The simulation analysis showed that when data were not missing at random, treatment effects were small, and the amount of missing data was substantial, the analysis method had an effect on the significance of the outcome. Careful attention must be paid when analyzing or appraising studies with missing data and small effects to ensure appropriate conclusions are drawn.

Short-term effects of fish and fish oil consumption on total and high molecular weight adiponectin levels in overweight and obese adults

OBJECTIVE

Fish or fish oil consumption may increase levels of total and high molecular weight (HMW) adiponectin, a hormone associated with anti-inflammatory and insulin-sensitising effects, however it is not known if the effects of the food and supplement are the same. The aim of this study was to compare the effect of consuming fish and fish oil supplements on plasma total and HMW adiponectin concentrations in overweight human participants.

MATERIALS/METHODS

29 overweight and obese participants underwent a two week run-in period, followed by a four week isocaloric dietary intervention which provided 1.8 g of long chain omega-3 polyunsaturated fatty acids (LC n-3 PUFA) in the form of either fish or fish oil supplements. Primary outcomes were changes in plasma total and HMW adiponectin. Secondary outcomes were changes in anthropometric variables, plasma insulin and glucose levels, and dietary intakes.

RESULTS

Changes in plasma HMW adiponectin during the intervention period were significantly different between groups (p=0.009). Mean HMW adiponectin increased by 0.29 μg/mL in the 'fish' group and decreased by 0.60 μg/mL in the 'supplement' group. There were no significant changes in other anthropometric and biochemical variables. Dietary data suggested the 'fish' group significantly increased their fish (p=0.001) and dietary LC n-3 PUFA (p=0.001) consumption over the course of the study.

CONCLUSIONS

Short-term consumption of fish and fish oil supplements did not have the same effects on HMW adiponectin levels. The impact of fish intake on HMW adiponectin levels may not be mediated by its LC n-3 PUFA content alone.

A school-based intervention to promote physical activity among adolescent girls: rationale, design, and baseline data from the Girls in Sport group randomised controlled trial

Background

Physical activity levels decline markedly among girls during adolescence. School-based interventions that are multi-component in nature, simultaneously targeting curricular, school environment and policy, and community links, are a promising approach for promoting physical activity. This report describes the rationale, design and baseline data from the Girls in Sport group randomised trial, which aims to prevent the decline in moderate-to-vigorous intensity physical activity (MVPA) among adolescent girls.

Methods/Design

A community-based participatory research approach and action learning framework are used with measurements at baseline and 18-month follow-up. Within each intervention school, a committee develops an action plan aimed at meeting the primary objective (preventing the decline in accelerometer-derived MVPA). Academic partners and the State Department of Education and Training act as critical friends. Control schools continue with their usual school programming. 24 schools were matched then randomized into intervention (n = 12) and control (n = 12) groups. A total of 1518 girls (771 intervention and 747 control) completed baseline assessments (86% response rate). Useable accelerometer data (≥10 hrs/day on at least 3 days) were obtained from 79% of this sample (n = 1199). Randomisation resulted in no differences between intervention and control groups on any of the outcomes. The mean age (SE) of the sample was 13.6 (± 0.02) years and they spent less than 5% of their waking hours in MVPA (4.85 ± 0.06).

Discussion

Girls in Sport will test the effectiveness of schools working towards the same goal, but developing individual, targeted interventions that bring about changes in curriculum, school environment and policy, and community links. By using community-based participatory research and an action learning framework in a secondary school setting, it aims to add to the body of literature on effective school-based interventions through promoting and sustaining increased physical activity participation among adolescent girls.

Trial Registration Number

Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12610001077055

A school-based intervention to promote physical activity among adolescent girls: rationale, design, and baseline data from the Girls in Sport group randomised controlled trial

BACKGROUND

Physical activity levels decline markedly among girls during adolescence. School-based interventions that are multi-component in nature, simultaneously targeting curricular, school environment and policy, and community links, are a promising approach for promoting physical activity. This report describes the rationale, design and baseline data from the Girls in Sport group randomised trial, which aims to prevent the decline in moderate-to-vigorous intensity physical activity (MVPA) among adolescent girls.

METHODS/DESIGN

A community-based participatory research approach and action learning framework are used with measurements at baseline and 18-month follow-up. Within each intervention school, a committee develops an action plan aimed at meeting the primary objective (preventing the decline in accelerometer-derived MVPA). Academic partners and the State Department of Education and Training act as critical friends. Control schools continue with their usual school programming. 24 schools were matched then randomized into intervention (n = 12) and control (n = 12) groups. A total of 1518 girls (771 intervention and 747 control) completed baseline assessments (86% response rate). Useable accelerometer data (≥ 10 hrs/day on at least 3 days) were obtained from 79% of this sample (n = 1199). Randomisation resulted in no differences between intervention and control groups on any of the outcomes. The mean age (SE) of the sample was 13.6 (± 0.02) years and they spent less than 5% of their waking hours in MVPA (4.85 ± 0.06).

DISCUSSION

Girls in Sport will test the effectiveness of schools working towards the same goal, but developing individual, targeted interventions that bring about changes in curriculum, school environment and policy, and community links. By using community-based participatory research and an action learning framework in a secondary school setting, it aims to add to the body of literature on effective school-based interventions through promoting and sustaining increased physical activity participation among adolescent girls.

TRIAL REGISTRATION NUMBER

Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12610001077055.

Validity of the BodyGem calorimeter and prediction equations for the assessment of resting energy expenditure in overweight and obese Saudi males

OBJECTIVE

To assess the accuracy of resting energy expenditure (REE) measurement in a sample of overweight and obese Saudi males, using the BodyGem device (BG) with whole room calorimetry (WRC) as a reference, and to evaluate the accuracy of predictive equations.

METHODS

Thirty-eight subjects (mean +/- SD, age 26.8+/- 3.7 years, body mass index 31.0+/- 4.8) were recruited during the period from 5 February 2007 to 28 March 2008. Resting energy expenditure was measured using a WRC and BG device, and also calculated using 7 prediction equations. Mean differences, bias, percent of bias (%bias), accurate estimation, underestimation and overestimation were calculated.

RESULTS

Repeated measures with the BG were not significantly different (accurate prediction: 81.6%; %bias 1.1+/- 6.3, p>0.24) with limits of agreement ranging from +242 to -200 kcal. Resting energy expenditure measured by BG was significantly less than WRC values (accurate prediction: 47.4%; %bias: 11.0+/- 14.6, p = 0.0001) with unacceptably wide limits of agreement. Harris-Benedict, Schofield and World Health Organization equations were the most accurate, estimating REE within 10% of measured REE, but none seem appropriate to predict the REE of individuals.

CONCLUSION

There was a poor agreement between the REE measured by WRC compared to BG or predictive equations. The BG assessed REE accurately in 47.4% of the subjects on an individual level.

Diet high in oat β-glucan activates the gut-hypothalamic (PYY₃₋₃₆-NPY) axis and increases satiety in diet-induced obesity in mice

This study tested the effects of (1→3),(1→4) β-D-glucan from oats, on activation of the gut-hypothalamic (PYY₃₋₃₆-NPY) axis, satiety, and weight loss in diet-induced obesity (DIO) mice. DIO mice were fed standard lab chow diets or varied doses of β-glucan for 6 weeks. Energy intake, satiety, body weight changes and peptide Y-Y₃₋₃₆ (PYY₃₋₃₆) were measured together with a satiety test and measurement of neuropeptide Y (NPY) mRNA expression in the hypothalamic arcuate nucleus (Arc). The average energy intake (-13%, p<0.05) and body weight gain was lower with increasing β-glucan over 6 wk with acute suppression of energy intake over 4 h. The highest β-glucan diet significantly increased plasma PYY₃₋₃₆, with suppression of Arc NPY mRNA.

The Nutrition and Enjoyable Activity for Teen Girls (NEAT girls) randomized controlled trial for adolescent girls from disadvantaged secondary schools: rationale, study protocol, and baseline results

BACKGROUND

Child and adolescent obesity predisposes individuals to an increased risk of morbidity and mortality from a range of lifestyle diseases. Although there is some evidence to suggest that rates of pediatric obesity have leveled off in recent years, this has not been the case among youth from low socioeconomic backgrounds. The purpose of this paper is to report the rationale, study design and baseline findings of a school-based obesity prevention program for low-active adolescent girls from disadvantaged secondary schools.

METHODS/DESIGN

The Nutrition and Enjoyable Activity for Teen Girls (NEAT Girls) intervention will be evaluated using a group randomized controlled trial. NEAT Girls is a 12-month multi-component school-based intervention developed in reference to Social Cognitive Theory and includes enhanced school sport sessions, interactive seminars, nutrition workshops, lunch-time physical activity (PA) sessions, PA and nutrition handbooks, parent newsletters, pedometers for self-monitoring and text messaging for social support. The following variables were assessed at baseline and will be completed again at 12- and 24-months: adiposity, objectively measured PA, muscular fitness, time spent in sedentary behaviors, dietary intake, PA and nutrition social-cognitive mediators, physical self-perception and global self-esteem. Statistical analyses will follow intention-to-treat principles and hypothesized mediators of PA and nutrition behavior change will be explored.

DISCUSSION

NEAT Girls is an innovative intervention targeting low-active girls using evidence-based behavior change strategies and nutrition and PA messages and has the potential to prevent unhealthy weight gain and reduce the decline in physical activity and poor dietary habits associated with low socio-economic status. Few studies have reported the long-term effects of school-based obesity prevention programs and the current study has the potential to make an important contribution to the field.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry No: ACTRN12610000330044.

The Nutrition and Enjoyable Activity for Teen Girls (NEAT girls) randomized controlled trial for adolescent girls from disadvantaged secondary schools: rationale, study protocol, and baseline results

BACKGROUND

Child and adolescent obesity predisposes individuals to an increased risk of morbidity and mortality from a range of lifestyle diseases. Although there is some evidence to suggest that rates of pediatric obesity have leveled off in recent years, this has not been the case among youth from low socioeconomic backgrounds. The purpose of this paper is to report the rationale, study design and baseline findings of a school-based obesity prevention program for low-active adolescent girls from disadvantaged secondary schools.

METHODS/DESIGN

The Nutrition and Enjoyable Activity for Teen Girls (NEAT Girls) intervention will be evaluated using a group randomized controlled trial. NEAT Girls is a 12-month multi-component school-based intervention developed in reference to Social Cognitive Theory and includes enhanced school sport sessions, interactive seminars, nutrition workshops, lunch-time physical activity (PA) sessions, PA and nutrition handbooks, parent newsletters, pedometers for self-monitoring and text messaging for social support. The following variables were assessed at baseline and will be completed again at 12- and 24-months: adiposity, objectively measured PA, muscular fitness, time spent in sedentary behaviors, dietary intake, PA and nutrition social-cognitive mediators, physical self-perception and global self-esteem. Statistical analyses will follow intention-to-treat principles and hypothesized mediators of PA and nutrition behavior change will be explored.

DISCUSSION

NEAT Girls is an innovative intervention targeting low-active girls using evidence-based behavior change strategies and nutrition and PA messages and has the potential to prevent unhealthy weight gain and reduce the decline in physical activity and poor dietary habits associated with low socio-economic status. Few studies have reported the long-term effects of school-based obesity prevention programs and the current study has the potential to make an important contribution to the field.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry No: ACTRN12610000330044.

Performance of body mass index in predicting diabetes and hypertension in the Eastern Province of Saudi Arabia

BACKGROUND AND OBJECTIVES

Body mass index (BMI) is the most widely used measure to define obesity and predict its complications, such as diabetes and hypertension, but its accuracy and usefulness in Saudi subjects is unknown. This study aimed to assess the validity of standard BMI cut-point values in the Saudi population.

SUBJECTS AND METHODS

197 681 adults participated in a cross-sectional study to detect diabetes and hypertension in the Saudi Eastern province in 2004/2005, with blood pressure, fasting blood sugar, height and weight measurements taken. Sensitivities, specificities, areas under the curves, predictive values, likelihood ratios, false positive, false negatives and total misclassification ratios were calculated for various BMI values determined from receiver operating characteristic (ROC) curves. The significance of the association between risk factors and BMI was assessed using regression analysis.

RESULTS

For the definition of overweight, ROC curve analysis suggested optimal BMI cut-offs of 28.50 to 29.50 in men and 30.50 to 31.50 in women, but the levels of sensitivity and specificity were too low to be of clinical value and the overall misclassification was unacceptably high across all the selected BMI values (>0.80). The relationship between BMI and the presence of diabetes and/or hypertension was not improved when a BMI of 25 was used. Using regression analyses, the odds ratios for hypertension and/or diabetes increased significantly from BMI values as low as 21-23 with no improvement in the diagnostic performance of BMI at these cutoffs.

CONCLUSION

In Saudi population, there is an increased risk of diabetes and hypertension relative to BMI, starting at a BMI as low as 21 but overall there is no cutoff BMI level with high predictive value for the development of these chronic diseases, including the WHO definition of obesity at BMI of 30.

Effects of nandrolone decanoate compared with placebo or testosterone on HIV-associated wasting

Objectives Current research is unclear about the most effective pharmacological agents for managing the loss of weight and fat-free mass common in HIV/AIDS. The aim of this study was to compare nandrolone decanoate with placebo and testosterone. Methods The study was a multicentre randomized double-blind placebo-controlled trial. Three hundred and three adult HIV-positive male patients with a weight loss of 5-15% in the last 12 months, or a body mass index of 17-19 kg/m(2), or a body cell mass/height ratio lower than 13.5 kg/m, were randomly assigned to receive nandrolone decanoate (150 mg), testosterone (250 mg) or placebo intramuscularly every 2 weeks for 12 weeks. Fat-free mass, weight, immune markers and perception of treatment were the main outcome measures. Results Treatment with nandrolone resulted in significantly greater increases in fat-free mass [mean increase 1.34 kg; 95% confidence interval (CI) 0.60; 2.08 kg] and in weight (mean increase 1.48 kg; 95% CI 0.82; 2.14 kg) compared with placebo. The mean increase in weight with nandrolone of 1.00 kg (95% CI 0.27; 1.74 kg) when compared with testosterone was significant, although the difference in fat free mass did not reach significance (mean increase 0.69 kg; 95% CI-0.13; 1.51 kg). Patient perception of benefit was significantly greater in the nandrolone group when compared with both the placebo and the testosterone groups. Conclusions Treatment with nandrolone decanoate increased body weight when compared with placebo and testosterone. Nandrolone decanoate treatment resulted in greater increases in fat-free mass than placebo and demonstrated a trend for a significant increase when compared with testosterone.

Investigating heterogeneity in studies of resting energy expenditure in persons with HIV/AIDS: a meta-analysis

BACKGROUND

There is conflict in the literature about the extent of alterations of resting energy expenditure (REE) in persons with HIV.

OBJECTIVE

The study was conducted to ascertain the mean difference in REE (in kJ) per kilogram of fat-free mass (FFM; REE/FFM) between HIV-positive subjects and control subjects and to investigate heterogeneity in the literature.

DESIGN

A meta-analysis comparing classical and Bayesian methods was conducted. Heterogeneity was investigated by using subgroup analysis, metaregression, and a mixed indirect comparison.

RESULTS

Of 58 studies meeting the inclusion criteria, 32 included both HIV-positive and control groups; 24 of these 32 were included. Thirty-seven studies were used in the mixed indirect comparison, and 30 were used in the subgroup comparisons of the HIV-symptomatic, lipodystrophy, weight-losing, and weight-stable subgroups and the healthy (HIV-negative) control group. Mean REE/FFM was significantly higher in 732 HIV-positive subjects than in 340 control subjects [11.93 kJ/kg (95% CI: 8.44,15.43 kJ/kg) and 12.47 kJ/kg (95% CI: 8.19,16.57 kJ/kg), classical and Bayesian random effects, respectively]; the test for heterogeneity was significant (P < 0.001). Both the mixed indirect comparison and the subgroup analysis indicated that REE/FFM was highest in the symptomatic subgroup; however, the small number of studies investigating symptomatic subjects limited statistical comparisons. The presence of lipodystrophy, use of highly active antiretroviral therapy, subject age, and method of body-composition measurement could not explain the heterogeneity in the data with the use of metaregression.

CONCLUSIONS

REE/FFM (kJ/kg) is significantly higher in HIV-positive subjects than in healthy control subjects. Symptomatic HIV infection may contribute to the variations reported in the literature.

Low plasma vitamin E levels in major depression: diet or disease?

OBJECTIVE

Levels of vitamin E have been reported to be lower in patients suffering major depression, but whether this is due to inadequate dietary intake or the pathophysiology of depression is not known, and was the subject of the present study.

SETTING

Wollongong, Australia.

METHODS

Plasma vitamin E (alpha-tocopherol) was measured in 49 adults with major depression, age (mean+/-s.d.): 47+/-12 y. In a subset (n=19) usual dietary intake of vitamin E was determined by diet history.

RESULTS

Subjects had significantly lower plasma alpha-tocopherol (4.71+/-0.13 mumol/mmol cholesterol) than has previously been reported for healthy Australians, and plasma alpha-tocopherol was inversely related to depression score (by Beck Depression Inventory) (r=-0.367, P<0.009). Diet analysis indicated that 89% of subjects met or exceeded the recommended intake for vitamin E, and dietary intake was not related to plasma alpha-tocopherol level in this subset.

CONCLUSION

These findings suggest that plasma levels of alpha-tocopherol are lower in depression, but this is not likely to be the result of inability to meet recommended dietary intake. .

Relative validity of a diet history interview in an intervention trial manipulating dietary fat in the management of Type II diabetes mellitus

BACKGROUND

This study assesses the relative validity of a diet history interview in 56 free-living individuals with Type II diabetes mellitus.

METHODS

The diet history interview was compared to a 3-day food record in a 1-year dietary intervention trial. The plausibility of energy intake data was examined throughout the trial. Paired data were compared for differences and the presence of systematic error was determined by Bland Altman analysis. Changes in accuracy and responsiveness were assessed over time.

RESULTS

The proportion of underreporters was larger in the diet history at baseline. Underrecording with the food record was more common in subjects with BMIs > 30 kg/m(2). There was no difference between paired dietary data from the two methods; however, data on fatty acids failed to correlate. These correlations improved when outliers were removed. There was no evidence of a relationship between bias and mean intake of dietary variables. Accuracy of diet history measurement did not change during the trial for energy or macronutrients, but data on protein and monounsaturated fat were both affected by BMI. The diet history was more responsive than the food record to changes in monounsaturated fatty acid intake after 3 months, but this changed at the end of the trial.

CONCLUSION

The diet history provided good estimates of energy and macronutrient intakes in a sample group with Type II diabetes mellitus. However, energy intake data revealed a high prevalence of underreporting especially in people with higher BMIs.

Calculating energy requirements for men with HIV/AIDS in the era of highly active antiretroviral therapy

OBJECTIVES

1. To determine if resting energy expenditure (REE) adjusted for body composition is elevated in HIV-positive males when compared with healthy controls in the era of highly active antiretroviral therapy. 2. To examine the accuracy of prediction equations for estimating REE in people with HIV. 3. To determine if REE adjusting for body composition is significantly different between those HIV-positive subjects reporting lipodystrophy (LD) or weight loss (>or=5%) and those who are weight stable when compared to controls.

DESIGN

Cross-sectional study.

SETTING

Tertiary referral hospital HIV unit and an outpatient clinic specializing in HIV care.

SUBJECTS

HIV-positive males (n=70) and healthy male controls (n=16).

METHODS

REE was measured using indirect calorimetry. Body composition was assessed using bioelectrical impedance analysis.

RESULTS

1. REE when adjusted for fat-free mass and fat mass using the general linear model (analysis of covariance) was greater in HIV-positive subjects than controls (7258+/-810 kJ, n=70 vs 6615+/-695 kJ, n=16, P<0.05). 2. The Harris and Benedict, Schofield, Cunningham and the two equations previously published by Melchior and colleagues in HIV-positive subjects all gave an estimate of REE significantly different from the measured REE in the HIV-positive subjects, therefore a new prediction equation was developed. The inability of the published equations to predict REE in the different HIV-positive subgroups reflected the heterogeneity in body composition. 3. REE adjusted for fat-free and fat mass was significantly greater in the both the HIV patients who were weight stable and those with lipodystrophy compared with the healthy controls.

CONCLUSION

REE is significantly higher in HIV-positive males when compared with healthy controls. Body composition abnormalities common in HIV render the use of standard prediction equations for estimating REE invalid. When measuring REE in HIV-positive males adjustment steps should include fat-free and fat mass.

Prevalence and predictors of HIV-associated weight loss in the era of highly active antiretroviral therapy

This study was a cross-sectional study of 122 HIV-positive subjects to determine the prevalence and predictors of weight loss in the era of highly active antiretroviral therapy (HAART). Forty per cent reported lipodystrophy, 40% had documented weight loss (mean 6.6 kg). Mean intake 13,400 kJ (118% of estimated requirements calculated using the Harris-Benedict equation). One hundred (82%) were taking antiretroviral therapy. Using forward stepwise logistic regression analysis only viral load (VL) was significantly associated with weight loss when intake, CD4 T-cell count, lipodystrophy, and age were entered into the model with VL (log copies/mL). Every one log increase in HIV VL was associated with an odds of weight loss of 1.58 (P=0.0008). Weight loss is still common in the HAART era. HIV VL was the most significant predictor of weight loss in this sample. Inadequate dietary intake and self-reported lipodystrophy were not related to weight loss in this population.

Relative bias in diet history measurements: a quality control technique for dietary intervention trials

OBJECTIVE

Investigation of relative bias in diet history measurement during dietary intervention trials.

DESIGN

Retrospective analysis of human dietary data from two randomised controlled trials examining modified fat diets in the prevention and treatment of type II diabetes mellitus.

SETTING

Wollongong, Australia.

SUBJECTS

Thirty-five overweight, otherwise healthy subjects in trial 1 and 56 subjects with diabetes in trial 2.

INTERVENTIONS

Diet history interviews and three-day weighed food records administered at one-month intervals in trial 1 and three-month intervals in trial 2.

RESULTS

In a cross-sectional bias analysis, graphs of the association between bias and mean dietary intake showed that bias decreased in higher carbohydrate consumers in trial 1 (r = -0.344, P < 0.05). No other significant associations were found. In a longitudinal analysis, bias did not change over time in either trial. There were no significant differences in bias magnitudes between the trials, with the exception of monounsaturated fat measurement where bias was significantly greater and more positive in trial 2, indicating overestimation of monounsaturated fat intake with the diet history. Subjects in control and intervention groups underestimated energy, fat, saturated fat and alcohol intakes with the diet history in both trials. Overweight and obese individuals appeared to make the greatest contribution to the overall underestimation of saturated fat intake by the diet history regardless of whether they were in the control or intervention group and whether they were healthy or had diabetes.

CONCLUSION

Bias in diet history measurement appears to be macronutrient-specific, with energy, fat and saturated fat consistently underreported in the interview by subjects with and without diabetes and in both intervention and control groups in a dietary intervention trial. Relative bias analysis appears to be an informative tool in quality control for dietary intervention trials when biochemical markers are unavailable.

The role of fats in the lifecycle stages: adolescence and young adulthood

Advice supporting regular physical activity, healthy food choices and smoking avoidance is definitely warranted in adolescents, particularly where early negative eating trends are evident. A difference in emphasis may be required for males and females with respect to physical activity and diet. The amount of dietary fat is important in maintaining energy balance, and the type of fat is important in reducing the development of heart disease. Low-fat foods are suitable at this lifestage, but it is also important to avoid sources of "hidden" saturated fatty acids (biscuits and fast foods) and to include sources of polyunsaturated and monounsaturated fatty acids (oils, margarine, lean meat, poultry and nuts).

A comparison of megestrol acetate, nandrolone decanoate and dietary counselling for HIV associated weight loss

This randomized, prospective study compared three treatments, nandrolone decanoate (ND), megestrol acetate (MA) or dietary counselling, for managing human immunodeficiency syndrome (HIV) associated weight loss. It was centred on a Tertiary referral hospital, Sydney, Australia. Fifteen patients were randomized to receive ND (100 mg/fortnight), or MA (400 mg/day) or dietary counselling for 12 weeks. Those patients randomized to dietary counselling were further randomized to receive nandrolone or megestrol after completing the dietary counselling arm. Weight, fat free mass (FFM), percentage body fat mass (FM), dietary intake and appetite were assessed before commencing and at the completion of each treatment arm. Weight increased significantly in all treatment arms (dietary counselling 1.13 kg +/- 0.36, nandrolone 4.01 kg +/- 1.68, megestrol 10.20 kg +/- 4.51, p < 0.05 paired t-test). FFM increased significantly in patients receiving ND (3.54 +/- 1.98 kg, p=0.001) and those receiving MA (2.76 +/- 0.55 kg, p=0.002), whereas the change in those receiving dietary counselling alone was not significant. Percentage body fat mass increased significantly only in those receiving MA (7.77 +/- 4.85%, p=0.049). The change in weight and percentage body fat mass was significantly greater in those receiving MA than the other two treatment arms. The increase in FFM was significantly greater in both the nandrolone and megestrol arms than the dietary counselling arm. It was concluded that ND and MA both resulted in an increase in FFM greater than dietary counselling alone. Megestrol produced a significantly greater increase in weight, percentage fat mass, intake and appetite than did the other two treatment arms, suggesting it may be the preferred agent, particularly in a palliative care setting in which weight, appetite and intake increase are desirable without regard to the composition of the body. The long-term use of these agents in people with HIV should be reviewed in the context of improved survival on highly active antiretroviral therapy regimens.