Potential contribution of vaccination uptake to occupational differences in risk of SARS-CoV-2: analysis of the ONS COVID-19 Infection Survey

OBJECTIVES

To assess variation in vaccination uptake across occupational groups as a potential explanation for variation in risk of SARS-CoV-2 infection.

DESIGN

We analysed data from the UK Office of National Statistics COVID-19 Infection Survey linked to vaccination data from the National Immunisation Management System in England from 1 December 2020 to 11 May 2022. We analysed vaccination uptake and SARS-CoV-2 infection risk by occupational group and assessed whether adjustment for vaccination reduced the variation in risk between occupational groups.

RESULTS

Estimated rates of triple vaccination were high across all occupational groups (80% or above), but were lowest for food processing (80%), personal care (82%), hospitality (83%), manual occupations (84%) and retail (85%). High rates were observed for individuals working in health (95% for office based, 92% for those in patient-facing roles) and education (91%) and office-based workers not included in other categories (90%). The impact of adjusting for vaccination when estimating relative risks of infection was generally modest (ratio of hazard ratios across all occupational groups reduced from 1.37 to 1.32), but was consistent with the hypothesis that low vaccination rates contribute to elevated risk in some groups.

CONCLUSIONS

Variation in vaccination coverage might account for a modest proportion of occupational differences in infection risk. Vaccination rates were uniformly very high in this cohort, which may suggest that the participants are not representative of the general population. Accordingly, these results should be considered tentative pending the accumulation of additional evidence.

Measurement of SARS-CoV-2 in air and on surfaces in Scottish hospitals

BACKGROUND

There are still uncertainties in our knowledge of the amount of SARS-CoV-2 virus present in the environment - where it can be found, and potential exposure determinants - limiting our ability to effectively model and compare interventions for risk management.

AIM

This study measured SARS-CoV-2 in three hospitals in Scotland on surfaces and in air, alongside ventilation and patient care activities.

METHODS

Air sampling at 200 L/min for 20 min and surface sampling were performed in two wards designated to treat COVID-19-positive patients and two non-COVID-19 wards across three hospitals in November and December 2020.

FINDINGS

Detectable samples of SARS-CoV-2 were found in COVID-19 treatment wards but not in non-COVID-19 wards. Most samples were below assay detection limits, but maximum concentrations reached 1.7×10³ genomic copies/m³ in air and 1.9×10⁴ copies per surface swab (3.2×10² copies/cm² for surface loading). The estimated geometric mean air concentration (geometric standard deviation) across all hospitals was 0.41 (71) genomic copies/m³ and the corresponding values for surface contamination were 2.9 (29) copies/swab. SARS-CoV-2 RNA was found in non-patient areas (patient/visitor waiting rooms and personal protective equipment changing areas) associated with COVID-19 treatment wards.

CONCLUSION

Non-patient areas of the hospital may pose risks for infection transmission and further attention should be paid to these areas. Standardization of sampling methods will improve understanding of levels of environmental contamination. The pandemic has demonstrated a need to review and act upon the challenges of older hospital buildings meeting current ventilation guidance.

Longitudinal changes in proportionate mortality due to COVID-19 by occupation in England and Wales

OBJECTIVE

This study aimed to understand whether the proportionate mortality of COVID-19 for various occupational groups has varied over the pandemic.

METHODS

We used the Office for National Statistics (ONS) mortality data for England and Wales. The deaths (20-64 years) were classified as either COVID-19-related using ICD-10 codes (U07.1, U07.2), or from other causes. Occupational data recorded at the time of death was coded using the SOC10 coding system into 13 groups. Three time periods (TP) were used: (i) January 2020 to September 2020; (ii) October 2020-May 2021; and (iii) June 2021-October 2021. We analyzed the data with logistic regression and compared odds of death by COVID-19 to other causes, adjusting for age, sex, deprivation, region, urban/rural and population density.

RESULTS

Healthcare professionals and associates had a higher proportionate odds of COVID-19 death in TP1 compared to non-essential workers but were not observed to have increased odds thereafter. Medical support staff had increased odds of death from COVID-19 during both TP1 and TP2, but this had reduced by TP3. This latter pattern was also seen for social care, food retail and distribution, and bus and coach drivers. Taxi and cab drivers were the only group that had higher odds of death from COVID-19 compared to other causes throughout the whole period under study [TP1: odds ratio (OR) 2.42, 95% confidence interval (CI) 1.99-2.93; TP2: OR 3.15, 95% CI 2.63-3.78; TP3: OR 1.7, 95% CI 1.26-2.29].

CONCLUSION

Differences in the odds of death from COVID-19 between occupational groups has declined over the course of the pandemic, although some occupations have remained relatively high throughout.

The relationship between greenspace and personal exposure to PM2.5 during walking trips in Delhi, India

The presence of urban greenspace may lead to reduced personal exposure to air pollution via several mechanisms, for example, increased dispersion of airborne particulates; however, there is a lack of real-time evidence across different urban contexts. Study participants were 79 adolescents with asthma who lived in Delhi, India and were recruited to the Delhi Air Pollution and Health Effects (DAPHNE) study. Participants were monitored continuously for exposure to PM_2.5 (particulate matter with an aerodynamic diameter of less than 2.5 μm) for 48 h. We isolated normal day-to-day walking journeys (n = 199) from the personal monitoring dataset and assessed the relationship between greenspace and personal PM_2.5 using different spatial scales of the mean Normalised Difference Vegetation Index (NDVI), mean tree cover (TC), and proportion of surrounding green land use (GLU) and parks or forests (PF). The journeys had a mean duration of 12.7 (range 5, 53) min and mean PM_2.5 personal exposure of 133.9 (standard deviation = 114.8) μg/m³. The within-trip analysis showed weak inverse associations between greenspace markers and PM_2.5 concentrations only in the spring/summer/monsoon season, with statistically significant associations for TC at the 25 and 50 m buffers in adjusted models. Between-trip analysis also indicated inverse associations for NDVI and TC, but suggested positive associations for GLU and PF in the spring/summer/monsoon season; no overall patterns of association were evident in the autumn/winter season. Associations between greenspace and personal PM_2.5 during walking trips in Delhi varied across metrics, spatial scales, and season, but were most consistent for TC. These mixed findings may partly relate to journeys being dominated by walking along roads and small effects on PM_2.5 of small pockets of greenspace. Larger areas of greenspace may, however, give rise to observable spatial effects on PM_2.5, which vary by season.

Occupational differences in SARS-CoV-2 infection: analysis of the UK ONS COVID-19 infection survey

BACKGROUND

Concern remains about how occupational SARS-CoV-2 risk has evolved during the COVID-19 pandemic. We aimed to ascertain occupations with the greatest risk of SARS-CoV-2 infection and explore how relative differences varied over the pandemic.

METHODS

Analysis of cohort data from the UK Office of National Statistics COVID-19 Infection Survey from April 2020 to November 2021. This survey is designed to be representative of the UK population and uses regular PCR testing. Cox and multilevel logistic regression were used to compare SARS-CoV-2 infection between occupational/sector groups, overall and by four time periods with interactions, adjusted for age, sex, ethnicity, deprivation, region, household size, urban/rural neighbourhood and current health conditions.

RESULTS

Based on 3 910 311 observations (visits) from 312 304 working age adults, elevated risks of infection can be seen overall for social care (HR 1.14; 95% CI 1.04 to 1.24), education (HR 1.31; 95% CI 1.23 to 1.39), bus and coach drivers (1.43; 95% CI 1.03 to 1.97) and police and protective services (HR 1.45; 95% CI 1.29 to 1.62) when compared with non-essential workers. By time period, relative differences were more pronounced early in the pandemic. For healthcare elevated odds in the early waves switched to a reduction in the later stages. Education saw raises after the initial lockdown and this has persisted. Adjustment for covariates made very little difference to effect estimates.

CONCLUSIONS

Elevated risks among healthcare workers have diminished over time but education workers have had persistently higher risks. Long-term mitigation measures in certain workplaces may be warranted.

A data linkage study of the effects of the Great Recession and austerity on antidepressant prescription usage

BACKGROUND

International literature shows unemployment and income loss during the Great Recession worsened population mental health. This individual-level longitudinal study examines how regional economic trends and austerity related to depression using administrative prescription data for a large and representative population sample.

METHODS

Records from a sample of the Scottish Longitudinal Study (N=86 500) were linked to monthly primary care antidepressant prescriptions (2009-15). Regional economic trends were characterized by annual full-time employment data (2004-14). Economic impact of austerity was measured via annual income lost per working age adult due to welfare reforms (2010-15). Sequence analysis identified new cases of antidepressant use, and group-based trajectory modelling classified regions into similar economic trajectories. Multi-level logistic regression examined relationships between regional economic trends and new antidepressant prescriptions. Structural equation mediation analysis assessed the contributory role of welfare reforms.

RESULTS

Employed individuals living in regions not recovering post-recession had the highest risk of beginning a new course of antidepressants (AOR 1.23; 95% CI 1.08-1.38). Individuals living in areas with better recovery trajectories had the lowest risk. Mediation analyses showed that 50% (95% CI 7-61%) of this association was explained by the impact of welfare benefit reforms on average incomes.

CONCLUSIONS

Following the Great Recession, local labour market decline and austerity measures were associated with growing antidepressant usage, increasing regional inequalities in mental health. The study evidences the impact of austerity on health inequalities and suggests that economic conditions and welfare policies impact on population health. Reducing the burden of mental ill-health primarily requires action on the social determinants.

Ultraviolet A radiation and COVID-19 deaths in the USA with replication studies in England and Italy

Background

Understanding factors impacting deaths from COVID‐19 is of the highest priority. Seasonal variation in environmental meteorological conditions affects the incidence of many infectious diseases and may also affect COVID‐19. Ultraviolet (UV) A (UVA) radiation induces release of cutaneous photolabile nitric oxide (NO) impacting the cardiovascular system and metabolic syndrome, both COVID‐19 risk factors. NO also inhibits the replication of SARS‐CoV2.

Objectives

To investigate the relationship between ambient UVA radiation and COVID‐19 deaths.

Methods

COVID‐19 deaths at the county level, across the USA, were modelled in a zero‐inflated negative‐binomial model with a random effect for states adjusting for confounding by demographic, socioeconomic and long‐term environmental variables. Only those areas where UVB was too low to induce significant cutaneous vitamin D3 synthesis were modelled. We used satellite‐derived estimates of UVA, UVB and temperature and relative humidity. Replication models were undertaken using comparable data for England and Italy.

Results

The mortality rate ratio (MRR) in the USA falls by 29% [95% confidence interval (CI) 40% to 15%) per 100 kJ m^–2 increase in mean daily UVA. We replicated this in independent studies in Italy and England and estimate a pooled decline in MRR of 32% (95% CI 48% to 12%) per 100 kJ m^–2 across the three studies.

Conclusions

Our analysis suggests that higher ambient UVA exposure is associated with lower COVID‐19‐specific mortality. Further research on the mechanism may indicate novel treatments. Optimized UVA exposure may have population health benefits.

Exposure to Solar UV During Outdoor Construction Work in Britain

Excessive exposure to ultraviolet (UV) radiation from the sun in summer can cause skin cancer and in Britain there are around 1500 new cases of non-melanoma skin cancer (NMSC) each year, caused by exposure to solar UV at work. Little is known about the magnitude of UV exposure amongst outdoor construction workers in Britain, although this is one of the main groups at risk. The aim of this paper is to summarise measurements of erythema-weighted UVB radiation amongst construction workers in Scotland and the Southeast of England and interpret the data in terms of the risk of NMSC. The measurements were made as part of an intervention study using short mobile phone text messages to alter worker behaviour to either reduce UV exposure in summer or increase serum vitamin D in winter; the intervention is only briefly reported here. Data were collected from 67 workers from 9 worksites, of whom 41 provided measures of UV exposure for 758 working days. Daily exposure ranged from 0 to 13.47 standard erythema dose (SED), with the mean exposure for outdoor workers being 2.0 SED and the corresponding value for indoor workers being 0.7 SED. These data were obtained from a sensor located on the back of the workers hard hat; others have measured exposure on the wrist or upper arm and these locations probably, on average, have higher levels of UV exposure. It is likely that an outdoor construction worker in Britain could accumulate sufficient solar UV exposure over 30-40 years of work to more than double their risk of NMSC. We argue that employers in Britain should take a more proactive approach to manage sun safety and they should take responsibility for skin health surveillance for their workers.

Use of sequence analysis for classifying individual antidepressant trajectories to monitor population mental health

BACKGROUND

Over the past decade, antidepressant prescriptions have increased in European countries and the United States, partly due to an increase in the number of new cases of mental illness. This paper demonstrates an innovative approach to the classification of population level change in mental health status, using administrative data for a large sample of the Scottish population. We aimed to identify groups of individuals with similar patterns of change in pattern of prescribing, validate these groups by comparison with other indicators of mental illness, and characterise the population most at risk of increasing mental ill health.

METHODS

National Health Service (NHS) prescription data were linked to the Scottish Longitudinal Study (SLS), a 5.3% sample of the Scottish population (N = 151,418). Antidepressant prescription status over the previous 6 months was recorded for every month for which data were available (January 2009-December 2014), and sequence dissimilarity was computed by optimal matching. Hierarchical clustering was used to create groups of participants who had similar patterns of change, with multi-level logistic regression used to understand group membership.

RESULTS

Five distinct prescription pattern groups were observed, indicating: no prescriptions (76%), occasional prescriptions (10%), continuation of prior use of prescriptions (8%), a new course of prescriptions started (4%) or ceased taking prescriptions (3%). Young, white, female participants, of low social grade, residing in socially deprived neighbourhoods, living alone, being separated/divorced or out of the labour force, were more likely to be in the group that started a new course of antidepressant prescriptions.

CONCLUSIONS

The use of sequence analysis for classifying individual antidepressant trajectories offers a novel approach for capturing population-level changes in mental health risk. By classifying individuals into groups based on their anti-depressant medication use we can better identify how over time, mental health is associated with individual risk factors and contextual factors at the local level and the macro political and economic scale.

Changing levels of local crime and mental health: a natural experiment using self-reported and service use data in Scotland

Background

This study contributes robust evidence on the association between mental health and local crime rates by showing how changing exposure to small area-level crime relates to self-reported and administrative data on mental health.

Methods

The study sample comprised 112 251 adults aged 16–60 years, drawn from the Scottish Longitudinal Study, a 5.3% representative sample of Scottish population followed across censuses. Outcomes were individual mental health indicators: self-reported mental illness from the 2011 Census and linked administrative data on antidepressants and antipsychotics prescribed through primary care providers in the National Health Service in 2010/2012. Crime rates at data zone level (500–1000 persons) were matched to the participants’ main place of residence, as defined by general practitioner patient registration duration during 2004/2006, 2007/2009 and 2010/12. Average neighbourhood crime exposure and change in area crime were computed. Covariate-adjusted logistic regressions were conducted, stratified by moving status.

Results

In addition to average crime exposure during follow-up, recent increases in crime (2007/2009–2010/2012) were associated with a higher risk of self-reported mental illness, among ‘stayers’ aged 16–30 years (OR=1.11; 95% CI 1.00 to 1.22), and among ‘movers’ aged 31–45 years (OR=1.07; 95% CI 1.01 to 1.13). Prescribed medications reinforced these findings; worsening crime rates were linked with antidepressant prescriptions among young stayers (OR=1.09; 95% CI 1.04 to 1.14) and with antipsychotic prescriptions among younger middle-aged movers (OR=1.11; 95% CI 1.01 to 1.23).

Conclusion

Changing neighbourhood crime exposure is related to individual mental health, but associations differ by psychiatric conditions, age and moving status. Crime reduction and prevention, especially in communities with rising crime rates, may benefit public mental health.

Neighborhood Crime and Psychotropic Medications: A Longitudinal Data Linkage Study of 130,000 Scottish Adults

INTRODUCTION

Although neighborhood crime has been associated with mental health problems, longitudinal research utilizing objective measures of small-area crime and mental health service use is lacking. This study examines how local crime is associated with newly prescribed psychotropic medications in a large longitudinal sample of Scottish adults and explores whether the relationships vary between sociodemographic groups.

METHODS

Data from the Scottish Longitudinal Study, a 5.3% representative sample of the population, were linked with police-recorded crime in 2011 for residential locality and with psychotropic medications from 2009 to 2014, extracted from the prescription data set of National Health Service Scotland. Individuals receiving medication during the first 6 months of observation were excluded; the remaining sample was followed for 5.5 years. Covariate-adjusted, multilevel mixed-effects logistic models estimated associations between area crime and prescriptions for antidepressants, antipsychotics, and anxiolytics (analyzed in 2018-2019).

RESULTS

After adjustment for individual and neighborhood covariates, findings on 129,945 adults indicated elevated risk of antidepressant (OR=1.05, 95% CI=1.00, 1.10) and antipsychotic (OR=1.20, 95% CI=1.03, 1.39), but not anxiolytic (OR=0.99, 95% CI=0.93, 1.05) medication in high-crime areas. Crime showed stronger positive association with antidepressants among individuals (especially women) aged 24-53 years in 2009 and with antipsychotics among men aged 44-53 years in 2009. Skilled workers and people from lower nonmanual occupations had increased risk of medications in high-crime areas.

CONCLUSIONS

Local crime is an important predictor of mental health, independent of individual and other contextual risk factors. Place-based crime prevention and targeting vulnerable groups may have benefits for population mental health.

The impact of the point-of-sale tobacco display ban on young people in Scotland: before-and-after study

Background

Tobacco displays at point of sale have been shown to increase young people’s pro-smoking attitudes, susceptibility to smoking and smoking initiation. In Scotland, legislation that prohibited tobacco point-of-sale displays was implemented in large stores (i.e. those > 280 m2) in April 2013 and in small retailers in April 2015.

Objective

To assess the impact of the point-of-sale tobacco display ban on young people’s exposure to tobacco advertising, their attitudes to smoking and smoking susceptibility, and their risk of smoking initiation.

Design

Multimodal before-and-after study design using mixed methods to collect data at baseline (2013) and then longitudinally for 4 years.

Setting

Four main study communities in the central belt of mainland Scotland, UK, purposively selected to reflect two levels of urbanity (urban vs. small town) and two levels of deprivation (high vs. medium/low). Four matched communities.

Participants

In the main study communities, 94 tobacco retail outlets. All Secondary 2 (aged 13 years) and Secondary 4 (aged 15 years) pupils in 2013 and 2014 together with all Secondary 1 to Secondary 6 (aged 12–17 years) pupils in 2015–17. This included 6612 pupils who completed 14,344 questionnaires over 5 years. Three hundred and eighty-two participants in 80 focus groups who were recruited from Secondary 2 and Secondary 4 in 2013–17. In matched communities, 24 retail panel members in 2013–17.

Main outcome measures

Tobacco product and tobacco storage visibility, density of retail outlets (the number of retailers in a pre-defined area such as a residential neighbourhood), tobacco product exposure, brand awareness, perceived accessibility of tobacco, pro-smoking attitudes, pro-smoking norms, smoking susceptibility and smoking initiation.

Data platform and methods

The study had four components – a mapping and spatial analysis of retail outlets; a tobacco marketing audit, including retail panel interviews in matched communities; school surveys; and focus group discussions with secondary school pupils.

Limitations

The study was based on a small number of communities and did not include communities in remote areas.

Results

Compliance with the point-of-sale legislation in Scotland was high. This led to a large reduction in the visibility of tobacco products in retail outlets. However, when the results were stratified by socioeconomic status, declines in retailer density, weighted by total product visibility, were restricted to the least disadvantaged tertile of participants. Nevertheless, the implementation of the legislation was associated with a reduction in risk of both smoking susceptibility and smoking initiation in young people, as well as a reduction in the perceived accessibility of tobacco and in pro-smoking attitudes after both the partial and the comprehensive bans were introduced.

Conclusions

The Scottish point-of-sale legislation has been successful in reducing the overall visibility of tobacco products and is associated with improvements in attitudinal and behavioural outcomes in young people. However, cues that tobacco is for sale are still highly visible, particularly in retail outlets in areas of deprivation. In addition, the increase in retailer density that was observed after 2015 increased inequalities in product visibility. There was also evidence that the emergence of e-cigarettes may have disrupted the full impact of the legislation.

Future work

Our research indicates that further research is needed to examine the longitudinal relationships between tobacco outlet availability and product visibility inequalities; and the impact of e-cigarettes and standardised packaging on smoking initiation and prevalence.

Funding

This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 8, No. 1. See the NIHR Journals Library website for further project information.

How has the introduction of point-of-sale legislation affected the presence and visibility of tobacco retailing in Scotland? A longitudinal study

BACKGROUND

Reducing the local availability of tobacco is identified as the 'next frontier' in tobacco control. This paper examines the roles of tobacco retail outlet density and tobacco visibility in changing exposure to tobacco retailing before and after the introduction of point-of-sale (POS) legislation in Scotland.

METHODS

National tobacco retailer register data were analysed to examine time trends in tobacco retailer density (2012-2017). Results were stratified by local authority, neighbourhood deprivation and urbanity. Next, an annual retail audit using a POS tobacco visibility tool assessed changes in total product visibility in all retail outlets in four study communities between 2013 and 2017. A longitudinal survey (2013-2017) of 5527 adolescents aged 12-17 in the four study communities enabled the calculation of residential and journey-to-school measures of tobacco retailer exposure. Trends were stratified by deprivation, urbanity and socioeconomic status.

RESULTS

Retail provision of tobacco declined following the introduction of the POS legislation in 2013. However, there were strong geographic differences; nationally, one-fifth of local authorities have increased provision since 2015. In the four study communities, tobacco retail provision was generally stable over the study period. Although product visibility of tobacco products reduced for adolescents there was growing socioeconomic disparity in the density of tobacco retailers and the visibility of tobacco storage.

CONCLUSIONS

The POS ban reduced exposure to tobacco products in communities across Scotland. However, tobacco products remain widely available, and there is growing socioeconomic disparity in the availability and visibility of tobacco.

Changing labour market conditions during the 'great recession' and mental health in Scotland 2007-2011: an example using the Scottish Longitudinal Study and data for local areas in Scotland

This paper reports research exploring how trends in local labour market conditions during the period 2007-2011 (early stages of the 'great recession') relate to reported mental illness for individuals. It contributes to research on spatio-temporal variation in the wider determinants of health, exploring how the lifecourse of places relates to socio-geographical inequalities in health outcomes for individuals. This study also contributes to the renewed research focus on the links between labour market trends and population health, prompted by the recent global economic recession. We report research using the Scottish Longitudinal Study (SLS), a 5.3% representative sample of the Scottish population, derived from census data (https://sls.lscs.ac.uk/). In Scotland, (2011) census data include self-reported mental health. SLS data were combined with non-disclosive information from other sources, including spatio-temporal trends in labour market conditions (calculated using trajectory modelling) in the 32 local authority areas in Scotland. We show that, for groups of local authorities in Scotland over the period 2007-2011, trends in employment varied. These geographically variable trends in employment rates were associated with inequalities in self-reported mental health across the country, after controlling for a number of other individual and neighbourhood risk factors. For residents of regions that had experienced relatively high and stable levels of employment the odds ratio for reporting a mental illness was significantly lower than for the 'reference group', living in areas with persistently low employment rates. In areas where employment declined markedly from higher levels, the odds ratio was similar to the reference group. The findings emphasise how changes in local economic conditions may influence people's health and wellbeing independently of their own employment status. We conclude that, during the recent recession, the economic life course of places across Scotland has been associated with individual mental health outcomes.

A randomised control crossover trial of a theory based intervention to improve sun-safe and healthy behaviours in construction workers: study protocol

BACKGROUND

Exposure to sunlight can have both positive and negative health impacts. Excessive exposure to ultra-violet (UV) radiation from the sun can cause skin cancer, however insufficient exposure to sunlight has a detrimental effect on production of Vitamin D. In the construction industry there are onsite proactive behaviours for safety, but sun-safety remains a low priority. There is limited research on understanding the barriers to adopting sun-safe behaviours and the association this may have with Vitamin D production. This paper reports a protocol for an intervention study, using text messaging in combination with a supportive smartphone App. The intervention aims to both reduce UV exposure during months with higher UV levels and promote appropriate dietary changes to boost Vitamin D levels during months with low UV levels.

METHOD/DESIGN

Approximately 60 construction workers will be recruited across the United Kingdom. A randomised control crossover trial (RCCT) will be used to test the intervention, with randomisation at site level - i.e. participants will receive both the control (no text messages or supportive App support) and intervention (daily text messages and supportive App). Using the Theory of Planned Behaviour (TPB) the intervention focuses on supporting sun-safety and healthy dietary decisions in relation to Vitamin D intake. The intervention emphasises cultivating the perception of normative support in the workplace, increasing awareness of control and self-efficacy in taking sun-protective behaviours, making healthier eating choices to boost Vitamin D, and tackling stigmas attached to image and group norms. Each study epoch will last 21 days with intervention text messages delivered on workdays only. The supportive App will provide supplementary information about sun protective behaviours and healthy dietary choices. The primary outcome measure is 25-hydroxy-Vitamin D [25(OH)D] level (obtained using blood spot sampling), which will be taken pre and post control and intervention periods. Secondary outcome measures are two-fold, (1) using the TPB to detect changes in behaviour, and (2) quantifying UV exposure during the UK peak radiation season (April-September) using body-mounted UV sensors.

DISCUSSION

This study will provide important information about the effectiveness of a technology-based intervention to promote sun-safety and healthy behaviours in outdoor construction workers.

TRIAL REGISTRATION

ISRCTN15888934 retrospectively registered 15.01.2018.

Land cover and air pollution are associated with asthma hospitalisations: A cross-sectional study

BACKGROUND

There is increasing policy interest in the potential for vegetation in urban areas to mitigate harmful effects of air pollution on respiratory health. We aimed to quantify relationships between tree and green space density and asthma-related hospitalisations, and explore how these varied with exposure to background air pollution concentrations.

METHODS

Population standardised asthma hospitalisation rates (1997-2012) for 26,455 urban residential areas of England were merged with area-level data on vegetation and background air pollutant concentrations. We fitted negative binomial regression models using maximum likelihood estimation to obtain estimates of asthma-vegetation relationships at different levels of pollutant exposure.

RESULTS

Green space and gardens were associated with reductions in asthma hospitalisation when pollutant exposures were lower but had no significant association when pollutant exposures were higher. In contrast, tree density was associated with reduced asthma hospitalisation when pollutant exposures were higher but had no significant association when pollutant exposures were lower.

CONCLUSIONS

We found differential effects of natural environments at high and low background pollutant concentrations. These findings can provide evidence for urban planning decisions which aim to leverage health co-benefits from environmental improvements.