Exposure to silicates and systemic autoimmune-related outcomes in rodents: a systematic review.

BACKGROUND: Autoimmunity can result from the interplay between genetic background and effects of environmental and/or occupational exposure to hazardous materials. Several compounds, including silica dust, have been linked with systemic autoimmunity and systemic autoimmune diseases, based on epidemiological evidence. For asbestos, a strong link with systemic autoimmune diseases does not yet exist, however, several studies have documented features of autoimmunity following asbestos exposure. Even so, human studies are limited in their ability to identify and examine isolated exposures, making it difficult to demonstrate causation or to assess pathogenic mechanisms. Therefore, this systematic review examines the existing animal evidence regarding autoimmunity and exposure to silicates (silica and asbestos). METHODS: PubMed and EMBASE were systematically searched for peer-reviewed studies examining systemic autoimmune disease-related outcomes after silicate exposure in rodents. Literature databases were searched up to September 2021 for studies written in English and where the full text was available. Search strings were established based on a PECO (Population, Exposure, Comparator, Outcome) format. After title, abstract, and full-text screening, thirty-four studies were identified for further analysis. Quality assessment through ToxR tool and qualitative analysis of the results was performed. RESULTS: Although there was significant heterogeneity in the included studies in terms of exposure protocol and genetic background of the rodent models used, it was noted that both genetic background and exposure to silicates [(crystalline) silica and asbestos] are highly relevant to the development of (sub-) clinical systemic autoimmune disease. CONCLUSION: Parallels were observed between the findings from the animal (this review) and human (epidemiological) studies, arguing that experimental animal models are valuable tools for examining exacerbation or development of autoimmune disease after silicate exposure. However, genetic background and synergism between exposures should be considered in future studies.

Two-year follow-up of a randomised controlled trial to assess the sustainability of a school intervention to improve the implementation of a school-based nutrition policy.

ISSUE ADDRESSED: School-based nutrition policies can have a positive effect on the school food environment. The primary aim of this study was to assess the primary school adherence to a mandatory state-wide healthy canteen policy 12 months after an effective multi-strategic implementation intervention concluded. METHODS: Primary schools were randomised to (a) a 12-14 months multi-strategic intervention or (b) no-intervention (control). The intervention aimed to improve implementation of a state-wide canteen policy by encouraging schools to remove unhealthy food and beverages (classified as ''red'' or ''banned'') from canteen menus and replace with healthy items (classified as ''green''). No implementation support was provided to either group by the research team between the 12 and 24 months data collection period. RESULTS: Seventy schools participated, of which 56 schools were assessed at 24-month follow-up. Intervention schools were less likely to have a menu which contained ''red/banned'' items at 24-month follow-up (RR = 2.28; 95% CI: 1.18-4.40; P = 0.01). Intervention schools, however, were not more likely than controls to have a menu which contained >50% ''green'' items at 24-month follow-up (RR = 1.29; 95% CI: 0.98-1.70; P = 0.10). Intervention schools were more likely to adhere to both policy components (no red/banned items and >50% green items on the menu) than control schools (RR = 2.61; 95% CI: 1.29-5.29; P = 0.006). Among intervention schools that were fully adherent to the policy following implementation support (12-month post baseline), all were also adherent at the 24-month follow-up. CONCLUSION: The intervention was effective in achieving long-term school adherence to a state-wide canteen policy at 24-month follow-up. SO WHAT?: The findings suggest that sustained improvements in implementation of school nutrition policies is possible following a period (12 months) of comprehensive implementation support.

A trial of a six-month sugar-sweetened beverage intervention in secondary schools from a socio-economically disadvantaged region in Australia.

OBJECTIVE: This study assessed the effectiveness of a school-based intervention in reducing adolescents' sugar-sweetened beverage (SSB) consumption and percentage of energy from SSBs. Secondary outcomes were SSB consumption within school, average daily energy intake, and body mass index z-scores. METHODS: Six secondary schools located in New South Wales, Australia were recruited to participate in a six-month pilot randomised controlled trial (1:1). The intervention included components targeting the school nutrition environment, curricula and community. Outcomes were collected via online surveys, observations, anthropometric measurements and project records. Between-group differences were assessed via linear mixed models. RESULTS: At the six-month intervention endpoint (n=862) there were no statistically significant differences between students in intervention or control schools for mean daily intake of SSBs (8.55mL; CI -26.77, 43.87; p=0.63), percentage daily energy from SSBs (0.12% kJ; CI -0.55, 0.80; p=0.72), or for secondary outcomes. Acceptability of the school-based strategies were high, however intervention fidelity varied across schools. CONCLUSION: While acceptable, improving fidelity of implementation and increasing the duration or intensity of the intervention may be required to reduce SSB intake. Implications for public health: Engaging parents and education stakeholders in the development phase to co-design interventions may prove beneficial in improving intervention fidelity and enhance behavioural outcomes.

Multi-strategic intervention to enhance implementation of healthy canteen policy: a randomised controlled trial.

BACKGROUND: Internationally, governments have implemented school-based nutrition policies to restrict the availability of unhealthy foods from sale. The aim of the trial was to assess the effectiveness of a multi-strategic intervention to increase implementation of a state-wide healthy canteen policy. The impact of the intervention on the energy, total fat, and sodium of children's canteen purchases and on schools' canteen revenue was also assessed. METHODS: Australian primary schools with a canteen were randomised to receive a 12-14-month, multi-strategic intervention or to a no intervention control group. The intervention sought to increase implementation of a state-wide healthy canteen policy which required schools to remove unhealthy items (classified as 'red' or 'banned') from regular sale and encouraged schools to 'fill the menu' with healthy items (classified as 'green'). The intervention strategies included allocation of a support officer to assist with policy implementation, engagement of school principals and parent committees, consensus processes with canteen managers, training, provision of tools and resources, academic detailing, performance feedback, recognition and marketing initiatives. Data were collected at baseline (April to September, 2013) and at completion of the implementation period (November, 2014 to April, 2015). RESULTS: Seventy schools participated in the trial. Relative to control, at follow-up, intervention schools were significantly more likely to have menus without 'red' or 'banned' items (RR = 21.11; 95% CI 3.30 to 147.28; p ≤ 0.01) and to have at least 50% of menu items classified as 'green' (RR = 3.06; 95% CI 1.64 to 5.68; p ≤ 0.01). At follow-up, student purchases from intervention school canteens were significantly lower in total fat (difference = -1.51 g; 95% CI -2.84 to -0.18; p = 0.028) compared to controls, but not in energy (difference = -132.32 kJ; 95% CI -280.99 to 16.34; p = 0.080) or sodium (difference = -46.81 mg; 95% CI -96.97 to 3.35; p = 0.067). Canteen revenue did not differ significantly between groups. CONCLUSION: Poor implementation of evidence-based school nutrition policies is a problem experienced by governments internationally, and one with significant implications for public health. The study makes an important contribution to the limited experimental evidence regarding strategies to improve implementation of school nutrition policies and suggests that, with multi-strategic support, implementation of healthy canteen policies can be achieved in most schools. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ( ACTRN12613000311752 ).

A randomised controlled trial of an intervention to increase the implementation of a healthy canteen policy in Australian primary schools: study protocol.

BACKGROUND: The implementation of healthy school canteen policies has been recommended as a strategy to help prevent unhealthy eating and excessive weight gain. Internationally, research suggests that schools often fail to implement practices consistent with healthy school canteen policies. Without a population wide implementation, the potential benefits of these policies will not be realised. The aim of this trial is to assess the effectiveness of an implementation intervention in increasing school canteen practices consistent with a healthy canteen policy of the New South Wales (NSW), Australia, government known as the 'Fresh Tastes @ School NSW Healthy School Canteen Strategy'. METHODS/DESIGN: The parallel randomised trial will be conducted in 70 primary schools located in the Hunter region of New South Wales, Australia. Schools will be eligible to participate if they are not currently meeting key components of the healthy canteen policy. Schools will be randomly allocated after baseline data collection in a 1:1 ratio to either an intervention or control group using a computerised random number function in Microsoft Excel. Thirty-five schools will be selected to receive a multi-component intervention including implementation support from research staff, staff training, resources, recognition and incentives, consensus and leadership strategies, follow-up support and implementation feedback. The 35 schools allocated to the control group will not receive any intervention support as part of the research trial. The primary outcome measures will be i) the proportion of schools with a canteen menu that does not contain foods or beverages restricted from regular sale ('red' and 'banned' items) and ii) the proportion of schools where healthy canteen items ('green' items) represent the majority (>50%) of products listed on the menu. Outcome data will be collected via a comprehensive menu audit, conducted by dietitians blind to group allocation. Intervention effectiveness will be assessed using logistic regression models adjusting for baseline values. DISCUSSION: The proposed trial will represent a novel contribution to the literature, being the first randomised trial internationally to examine the effectiveness of an intervention to facilitate implementation of a healthy canteen policy. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12613000311752.