Altered response of the anterolateral abdominal muscles to simulated weight-bearing in subjects with low back pain

An important aspect of neuromuscular control at the lumbo-pelvic region is stabilization. Subjects with low back pain (LBP) have been shown to exhibit impairments in motor control of key muscles which contribute to stabilization of the lumbo-pelvic region. However, a test of automatic recruitment that relates to function has been lacking. A previous study used ultrasound imaging to show that healthy subjects automatically recruited the transversus abdominis (TrA) and internal oblique (IO) muscles in response to a simulated weight-bearing task. This task has not been investigated in subjects with LBP. The aim of this study was to compare the automatic recruitment of the abdominal muscles among subjects with and without LBP in response to the simulated weight-bearing task. Twenty subjects with and without LBP were tested. Real-time ultrasound imaging was used to assess changes in thickness of the TrA and internal oblique IO muscles as well as lateral movement ("slide") of the anterior fascial insertion of the TrA muscle. Results showed that subjects with LBP showed significantly less shortening of the TrA muscle (P < 0.0001) and greater increases in thickness of the IO muscle (P = 0.002) with the simulated weight-bearing task. There was no significant difference between groups for changes in TrA muscle thickness (P = 0.055). This study provides evidence of changes in motor control of the abdominal muscles in subjects with LBP. This test may provide a functionally relevant and non-invasive method to investigate the automatic recruitment of the abdominal muscles in people with and without LBP.

The role of parity in gestational weight gain and postpartum weight retention

OBJECTIVES: Parity, excessive gestational weight gain (GWG), and postpartum weight retention (PPWR) have been identified as risk factors for maternal obesity. The aim of this study was to explore whether GWG and PPWR at 6 and 12 months after birth differed for primiparous and multiparous Australian women. METHODS: One hundred thirty-eight Australian women provided weight measures in early to mid pregnancy (M = 16.7 weeks, SD = 2.3), late pregnancy (M = 37.7 weeks, SD = 2.4), 6 months postpartum (M = 6.1 months, SD = 1.4), and 12 months postpartum (M = 12.6 months, SD = 0.7). Height, parity, and demographic information were also collected. Prepregnancy body mass index (BMI), total GWG, incidence of excessive GWG, as well as change in BMI and BMI category from prepregnancy to 6 and 12 months postpartum were computed. Differences between primiparous and multiparous women were compared using analysis of covariance (controlling for age, prepregnancy BMI, and GWG) and χ(2) test of independence. RESULTS: Seventy women (50.7%) were primiparous and 68 women (49.3%) were multiparous. Primiparous women were more likely to retain weight at 12 months postpartum than multiparous women (p = .021; Cohen's d = .24). This difference was not reflected when analyzing change in BMI categories from prepregnancy to the postpartum. CONCLUSIONS: Evidence for the role of parity in PPWR is inconclusive. Future research should consider the temporal development of PPWR in primiparous and multiparous women, leading to tailored care in the postpartum period to help women return to a healthy prepregnancy weight.

Psychosocial factors and excessive gestational weight gain: the effect of parity in an Australian cohort

OBJECTIVES: psychosocial variables can be protective or risk factors for excessive gestational weight gain (GWG). Parity has also been associated with GWG; however, its effect on psychosocial risk factors for GWG is yet to be determined. The aim of this study was to investigate if, and how, psychosocial factors vary in their impact on the GWG of primiparous and multiparous women. DESIGN/PARTICIPANTS: pregnant women were recruited in 2011 via study advertisements placed in hospitals, online, in parenting magazines, and at baby and children's markets, resulting in a sample of 256 women (113 primiparous, 143 multiparous). Participants completed questionnaires at 16-18 weeks' gestation and their pregravid BMI was recorded. Final weight before delivery was measured and used to calculate GWG. FINDINGS: the findings revealed that primiparous women had significantly higher feelings of attractiveness (a facet of body attitude; p=0.01) than multiparous women. Hierarchical regressions revealed that in the overall sample, increased GWG was associated significantly with lower pre-pregnancy BMI (standardised coefficient β=-0.39, p<0.001), higher anxiety symptoms (β=0.25, p=0.004), and reduced self-efficacy to eat a healthy diet (β=-0.20, p=0.02). Although higher GWG was predicted significantly by decreased feelings of strength and fitness for primiparous women (β=-0.25, p=0.04) and higher anxiety was related significantly to greater GWG for multiparous women (β=0.43, p<0.001), statistical comparison of the model across the two groups suggested the magnitude of these effects did not differ across groups (p>0.05). CONCLUSIONS/IMPLICATIONS FOR PRACTICE: the findings suggest that psychosocial screening and interventions by healthcare professionals may help to identify women who are at risk of excessive GWG, and there may be specific psychosocial factors that are more relevant for each parity group.

Opportunities to promote healthy maternal weight during and following pregnancy

 This thesis has identified opportunities for provision of support for women to attain a healthy weight and healthy diet and physical activity behaviours during and following pregnancy. A better understanding of strategies to promote optimal support to women during the postpartum period has been achieved.

Contact & connect-an intervention to reduce depression stigma and symptoms in construction workers: protocol for a randomised controlled trial

BACKGROUND: Males employed in the construction industry have high rates of suicide. Although reasons underpinning this risk are multifaceted, poor help-seeking and stigma are represent major contributors. Males in the construction industry are also exposed to other risk factors for mental ill health and suicide, including unemployment. Sigma-reducing interventions that are accessible and attractive to recently unemployed males in the construction industry could therefore improve help-seeking, and address depression and suicidal behaviour in this population. METHODS/DESIGN: Contact&Connect will use a parallel individual randomized design to evaluate the effectiveness of a multimedia-based intervention aimed at reducing stigma. The intervention consists of a package of 12 brief contact interventions (BCIs) delivered over a six month period. BCIs will direct participants to informational programs and microsites. Content will address three major themes: debunking depression myths and stereotypes, normalisation, and empowerment. Target enrolment is 630 (315 in each arm), each to be followed for 12 months. Eligible participants will be males, between 30 and 64 years, unemployed at the time of recruitment, registered with Incolink (a social welfare trustee company for unemployed members of the construction industry), and own a smart phone with enabled internet connectivity. DISCUSSION: At present, there are no programs that have been shown to be effective in reducing stigma in the blue-collar male population. Contact&Connect promises to provide a tailored, efficient, and scalable approach to reducing stigma, depressive symptoms and suicidality among unemployed males. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Register ACTRN12615000792527  (date of registration: 30 July, 2015).

Thermal and rheological characteristics of biobased carbon fiber precursor derived from low molecular weight organosolv lignin

In the present work, electrospinnability as well as thermal, rheological, and morphological characteristics of low molecular weight hardwood organosolv lignin, as a potential precursor for carbon fiber, was investigated. Submicromter biobased fibers were electrospun from a wide range of polymer solutions with different ratios of organosolv lignin to polyacrylonitrile (PAN). Rheological studies were conducted by measuring viscosity, surface tension, and electrical conductivity of hybrid polymer solutions, and used to correlate electrospinning behavior of solutions with the morphology of the resultant electrospun composite fibers. Using scanning electron microscopy (SEM) images, the solutions that led to the formation of bead-free uniform fibers were found. Differential scanning calorimetry (DSC) analysis revealed that lignin-based fibers enjoy higher decomposition temperatures than that of pure PAN. Thermal stability of the lignin-based fibers was investigated by thermogravimetric analysis (TGA) indicating a high carbon yield of above 50% at 600 °C, which is highly crucial in the production of low-cost carbon fiber. It was also observed that organosolv lignin synergistically affects thermal decomposition of composite fibers. A significant lower activation energy was found for the pyrolysis of lignin-derived electrospun fibers compared to that of pure PAN.

The influence on population weight gain and obesity of the macronutrient composition and energy density of the food supply

Rates of overweight and obesity have increased dramatically in all regions of the world over the last few decades. Almost all of the world's population now has ubiquitous access to low-cost, but highly-processed, energy-dense, nutrient-poor food products. These changes in the food supply, rather than decreases in physical activity, are most likely the primary driver of population weight gain and obesity. To-date, the majority of prevention efforts focus on personalised approaches targeting individuals. Population-wide food supply interventions addressing sodium and trans fat reduction have proven highly effective and comparable efforts are now required to target obesity. The evidence suggests that strategies focusing upon reducing the energy density and portion size of foods will be more effective than those targeting specific macronutrients. Government leadership, clearly specified targets, accountability and transparency will be the key to achieving the food supply changes required to address the global obesity epidemic.

A path model of psychosocial and health behaviour change predictors of excessive gestational weight gain

This study aimed to evaluate a conceptual model of psychosocial, behaviour change, and behavioural predictors of excessive gestational weight gain (GWG). Background: Excessive GWG can place women and their babies at risk of poor health outcomes, including obesity. Models of psychosocial and behaviour change predictors of excessive GWG have not been extensively explored; understanding the mechanisms leading to excess GWG will provide crucial evidence towards the development of effective interventions. Method: Two hundred and eighty-eight pregnant women (≤18 weeks gestation) were recruited to a prospective study. Demographic, psychosocial, health behaviour change, and behavioural factors were assessed at 17 (Time 1, T1) and 33 weeks (Time 2, T2) gestation. Pre-pregnancy and final pregnancy weight were obtained and women were classified with/without excessive GWG. Logistic regressions refined the list of predictors of excessive GWG; variables with p < .1 were included in a path analysis. Results: Age, family income, T2 depression, T2 pregnancy-specific coping, T1 buttocks dissatisfaction, T2 GWG-specific self-efficacy, T1 dietary readiness, T1 dietary importance, and T1 vegetable intake predicted excessive GWG in the logistic regressions and were included in the path model. The baseline path model demonstrated poor fit. Once statistically and theoretically plausible paths were added, adequate model fit was achieved (χ² = 21.61(9), p < .05; RMSEA = .07; CFI = .93); this revised model explained 19.5% of the variance in excessive GWG. Women with high T1 buttocks dissatisfaction were more likely to exhibit low levels of dietary readiness. Women with low dietary readiness were more likely to have a lower vegetable intake, which predicted excessive GWG. Women with higher T2 depressive symptoms were more likely to report lower GWG self-efficacy and gain excessively. Conclusion: Future behavioural GWG trials should consider combining psychosocial and health behaviour change factors to optimise GWG.

Lay definitions of ideal weight and overweight

OBJECTIVE: To describe lay definitions of ideal weight and overweight, to determine whether they correspond with current health definitions, and to examine the relationship between lay definitions and weight-control behaviour.

DESIGN: Cross-sectional survey of a representative sample of adults from Victoria, Australia.

SUBJECTS: 1342 men and women, aged 18 y and older from across the weight spectrum.

MEASURES: Questionnaire-based measures of current height and weight to determine body mass index (BMI); weight that is considered to be ideal; weight that is considered to be overweight; current weight-control behaviour.

RESULTS: The BMI at which women considered themselves to be at their ideal weight was significantly lower than that for men. For both men and women, the BMI defined as ideal increased with age and with current weight. The average BMI at which women considered themselves to be overweight was significantly lower than that for men, and was well within the acceptable BMI range. Just over two-thirds of men, defined overweight at a level higher than the current cutoff of 25 kg/m2. For both men and women, the BMI defined as overweight increased with age and with current weight.

CONCLUSION: Lay definitions of ideal weight and overweight deviate substantially from health definitions. Public health initiatives should stress that many women are already a healthy weight, and encourage these women to focus their efforts on weight maintenance rather than weight loss. Since so few men have weight goals that are consistent with current health recommendations, it will be important to raise their awareness of what constitutes a healthy weight.

Depressive symptomatology, weight status and obesogenic risk among Australian adolescents: a prospective cohort study

OBJECTIVES: Adolescence is a period of increased risk for mental health problems and development of associated lifestyle risk behaviours. This study examined cross-sectional and longitudinal associations between obesogenic risk factors, weight status, and depressive symptomatology in a cohort of Australian adolescents.

DESIGN: Prospective cohort study.

SETTING: The study used repeated measures data from the Australian Capital Territory (ACT) It's Your Move project, an Australian community-based obesity prevention intervention. Intervention effect was non-significant therefore intervention and comparison groups were combined in this study.

PARTICIPANTS: Total sample was 634 secondary school students (female n=338, male n=296) with mean age 13 years (SD=0.6) at baseline (2012) and 15 years (SD=0.6) at follow-up (2014) recruited from 6 government secondary schools in the ACT.

PRIMARY AND SECONDARY OUTCOMES MEASURES: Primary outcome was depressive symptomatology measured by Short Mood and Feelings Questionnaire. Secondary outcomes were weight status, physical activity, screen time and diet related measures.

RESULTS: Increased physical activity was associated to lower depressive symptomatology among males (OR=0.35, p<0.05). Sweet drink (OR=1.15, p<0.05) and takeaway consumption (OR=1.84, p<0.05) were associated with higher levels of depressive symptomatology among females at follow-up. Males who were classified as overweight or obese at baseline, and remained so over the study period, were at increased risk of depressive symptomatology at follow-up (b=1.63, 95% CI 0.33 to 2.92). Inactivity among males over the 2-year study period was predictive of higher depressive symptomatology scores at follow-up (b=2.55, 95% CI 0.78 to 4.32). For females, those who increased their consumption of takeaway foods during the study period were at increased risk for developing depressive symptomatology (b=1.82, 95% CI -0.05 to 3.71).

CONCLUSIONS: There are multiple, probably complex, relationships between diet, physical activity and outcomes of obesity and mental health as well as between the outcomes themselves. Healthier diets and increased physical activity should be foundations for healthier body weight and mental health.

Nutritional intervention to prevent weight gain in patients commenced on olanzapine: a randomized controlled trial

Objective: Olanzapine is the most commonly prescribed atypical antipsychotic medication in Australia. Research reports an average weight gain of between 4.5 and 7 kg in the 3 months following its commencement. Trying to minimize this weight gain in a population with an already high prevalence of obesity, mortality and morbidity is of clinical and social importance. This randomized controlled trial investigated the impact of individual nutrition education provided by a dietitian on weight gain in the 3 and 6 months following the commencement of olanzapine.


Method: Fifty-one individuals (29 females, 22 males) who had started on olanzapine in the previous 3 months (mean length of 27 days ± 20) were recruited through Peninsula Health Psychiatric Services and were randomly assigned to either the intervention (n = 29) or the control group (n = 22). Individuals in the intervention group received six 1 hour nutrition education sessions over a 3-month period. Weight, waist circumference, body mass index (BMI) and qualitative measures of exercise levels, quality of life, health and body image were collected at baseline at 3 and 6 months.


Results: After 3 months, the control group had gained significantly more weight than the treatment group (6.0 kg vs 2.0 kg, p ≤ 0.002). Weight gain of more than 7% of initial weight occurred in 64% of the control group compared to 13% of the treatment group. The control group's BMI increased significantly more than the treatment group's (2 kg/m2vs 0.7 kg/m2, p ≤ 0.03). The treatment group reported significantly greater improvements in moderate exercise levels, quality of life, health and body image compared to the controls. At 6 months, the control group continued to show significantly more weight gain since baseline than the treatment group (9.9 kg vs 2.0 kg, p ≤ 0.013) and consequently had significantly greater increases in BMI (3.2 kg/m2vs 0.8 kg/m2, p ≤ 0.017).

Engaging patients, clinicians and health funders in weight management: the Counterweight Programme

Background. The Counterweight Programme provides an evidence based and effective approach for weight management in routine primary care. Uptake of the programme has been variable for practices and patients.

Aim. To explore key barriers and facilitators of practice and patient engagement in the Counterweight Programme and to describe key strategies used to address barriers in the wider implementation of this weight management programme in UK primary care.

Methods. All seven weight management advisers participated in a focus group. In-depth interviews were conducted with purposeful samples of GPs (n = 7) and practice nurses (n = 15) from 11 practices out of the 65 participating in the programme. A total of 37 patients participated through a mixture of in-depth interviews (n = 18) and three focus groups. Interviews and focus groups were analysed for key themes that emerged.

Results. Engagement of practice staff was influenced by clinicians’ beliefs and attitudes, factors relating to the way the programme was initiated and implemented, the programme content and organizational/contextual factors. Patient engagement was influenced by practice endorsement of the programme, clear understanding of programme goals, structured proactive follow-up and perception of positive outcomes.

Conclusions. Having a clear understanding of programme goals and expectations, enhancing self-efficacy in weight management and providing proactive follow-up is important for engaging both practices and patients. The widespread integration of weight management programmes into routine primary care is likely to require supportive public policy.

The Counterweight Programme: prevalence of CVD risk factors by body mass index and impact of a 10% weight change

Objectives

To examine relationships between body mass index (BMI), prevalence of physician-recorded cardiovascular disease (CVD) risk factors in primary care, and changes in risk with 10% weight change.

Methods

The Counterweight Project conducted a baseline cross-sectional survey of medical records of 6150 obese (BMI ≥ 30 kg/m2), 1150 age- and sex-matched overweight (BMI 25 to <30 kg/m2), and 1150 age- and sex-matched normal weight (BMI 18.5 to <25 kg/m2) controls, in primary care. Data were collected for the previous 18 months to examine BMI and disease prevalence, and then modelled to show the potential effect of 10% weight loss or gain on risk.

Results

Obese patients develop more CVD risk factors than normal weight controls. BMI ≥ 40 kg/m2 exhibits increased prevalence of type 2 diabetes mellitus (DM), odds ratio (OR) men: 6.16 (p < 0.001); women: 7.82 (p < 0.001) and hypertension OR men: 5.51 (p < 0.001); women: 4.16 (p < 0.001). Dyslipidaemia peaked around BMI 35 to <37.5 kg/m2, OR men: 3.26 (p < 0.001); women 3.76 (p < 0.001) and CVD at BMI 37.5 to <40 kg/m2 in men, OR 4.48 (p < 0.001) and BMI ≥ 40 kg/m2 in women, OR 3.98 (p < 0.001).

A 10% weight loss from the sample mean of 32.5 kg/m2 reduced the OR for type 2 DM by 30% and CVD by 20%, while 10% weight gain increased type 2 DM risk by more than 35% and CVD by 20%.

Conclusion

Obesity plays a fundamental role in CVD risk, which is reduced with weight loss. Weight management intervention strategies should be a public health priority to reduce the burden of disease in the population.

A new evidence-based approach to weight management in primary care: the Counterweight Programme

Background/Aims Obesity has become a global epidemic, and a major preventable cause of morbidity and mortality. Management strategies and treatment protocols are however poorly developed and evaluated. The aim of the Counterweight Programme is to develop an evidence-based model for the management of obesity in primary care.

Methods The Counterweight Programme is based on the theoretical model of Evidence-Based Quality Assessment aimed at improving the management of obese adults (18–75 years) in primary care. The model consists of four phases: (1) practice audit and needs assessment, (2) practice support and training, (3) practice nurse-led patient intervention, and (4) evaluation. Patient intervention consisted of screening and treatment pathways incorporating evidence-based approaches, including patient-centred goal setting, prescribed eating plans, a group programme, physical activity and behavioural approaches, anti-obesity medication and weight maintenance strategies. Weight Management Advisers who are specialist obesity dietitians facilitated programme implementation. Eighty practices were recruited of which 18 practices were randomized to act as controls and receive deferred intervention 2 years after the initial audit.

Results By February 2004, 58 of the 62 (93.5%) intervention practices had been trained to run the intervention programme, 47 (75.8%) practices were active in implementing the model and 1256 patients had been recruited (74% female, 26% male, mean age 50.6 years, SD 14). At baseline, 75% of patients had at one or more co-morbidity, and the mean body mass index (BMI) was 36.9 kg/m2 (SD 5.4). Of the 1256 patients recruited, 91% received one of the core lifestyle interventions in the first 12 months. For all patients followed up at 12 months, 34% achieved a clinical meaningful weight loss of 5% or more. A total of 51% of patients were classed as compliant in that they attended the required level of appointments in 3, 6, and 12 months. For fully compliant patients, weight loss improved with 43% achieving a weight loss of 5% or more at 12 months.

Conclusion The Counterweight Programme is an evidence-based weight management model which is feasible to implement in primary care.

Long-term cost-effectiveness of weight management in primary care

Background:  As obesity prevalence and health-care costs increase, Health Care providers must prevent and manage obesity cost-effectively.

Methods:  Using the 2006 NICE obesity health economic model, a primary care weight management programme (Counterweight) was analysed, evaluating costs and outcomes associated with weight gain for three obesity-related conditions (type 2 diabetes, coronary heart disease, colon cancer). Sensitivity analyses examined different scenarios of weight loss and background (untreated) weight gain.

Results:  Mean weight changes in Counterweight attenders was −3 kg and −2.3 kg at 12 and 24 months, both 4 kg below the expected 1 kg/year background weight gain. Counterweight delivery cost was £59.83 per patient entered. Even assuming drop-outs/non-attenders at 12 months (55%) lost no weight and gained at the background rate, Counterweight was ‘dominant’ (cost-saving) under ‘base-case scenario’, where 12-month achieved weight loss was entirely regained over the next 2 years, returning to the expected background weight gain of 1 kg/year. Quality-adjusted Life-Year cost was £2017 where background weight gain was limited to 0.5 kg/year, and £2651 at 0.3 kg/year. Under a ‘best-case scenario’, where weights of 12-month-attenders were assumed thereafter to rise at the background rate, 4 kg below non-intervention trajectory (very close to the observed weight change), Counterweight remained ‘dominant’ with background weight gains 1 kg, 0.5 kg or 0.3 kg/year.

Conclusion:  Weight management for obesity in primary care is highly cost-effective even considering only three clinical consequences. Reduced healthcare resources use could offset the total cost of providing the Counterweight Programme, as well as bringing multiple health and Quality of Life benefits.