The effect of monthly vitamin D supplementation on fractures: a tertiary outcome from the population-based, double-blind, randomised, placebo-controlled D-Health trial

BACKGROUND

Low serum 25-hydroxy vitamin D concentration is associated with increased fracture risk. It is uncertain whether vitamin D supplementation reduces fractures, or whether intermittent doses are harmful. We aimed to investigate if supplementing adults living in Australia with monthly doses of 60 000 international units (IU) vitamin D₃ for 5 years or less altered the rate of fractures.

METHODS

We did a population-based, double-blind, randomised, placebo-controlled trial of oral vitamin D₃ supplementation (60 000 IU per month) for up to 5 years in adults aged 60-84 years living in Australia. We randomly assigned (1:1) 21 315 participants to either vitamin D or placebo. We ascertained fractures through linkage with administrative datasets. The main outcome was total fractures. Additional outcomes were non-vertebral, major osteoporotic (hip, wrist, proximal humerus, and spine), and hip fractures. We excluded participants (989 [4·6%]) without linked data, and estimated hazard ratios (HRs) and 95% CIs using flexible parametric survival models. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12613000743763, and the trial intervention ended in February, 2020.

FINDINGS

Between Feb 14, 2014, and June 17, 2015, we recruited 21 315 participants. For the current analysis, we included 20 326 participants (vitamin D 10 154 [50·0%]; placebo 10 172 [50·0%]). 9295 (45·7%) of 20 326 participants were women and the mean age was 69·3 years (SD 5·5). Over a median follow-up of 5·1 years (IQR 5·1-5·1), 568 (5·6%) participants in the vitamin D group and 603 (5·9%) in the placebo group had one or more fractures. There was no effect on fracture risk overall (HR 0·94 [95% CI 0·84-1·06]), and the interaction between randomisation group and time was not significant (p=0·14). However, the HR for total fractures appeared to decrease with increasing follow-up time. The overall HRs for non-vertebral, major osteoporotic, and hip fractures were 0·96 (95% CI 0·85-1·08), 1·00 (0·85-1·18), and 1·11 (0·86-1·45), respectively.

INTERPRETATION

These findings do not support concerns that bolus doses of vitamin D administered monthly increase fracture risk. Long-term supplementation might reduce the incidence of total fractures, but additional research is needed to clarify this effect.

FUNDING

Australian National Health and Medical Research Council.

Cancer and Ongoing Climate Change: Who Are the Most Affected?

Cancer has become the leading cause of premature death in many counties in recent decades. Previous studies showed plenty of evidence that control of modifiable risk factors would reduce the cancer burden. Since modifiable risk factors could be eliminated by changing the lifestyles of individuals, a greater uptake of modifiable risk factors is critical to reducing cancer burden and inequality in cancer survival. However, climate change will widen cancer inequities through its complex connections with modifiable risk factors. In this perspective, complex connections between climate change and cancer risks via modifiable risk factors, including abnormal temperature, UV, air pollution, natural disasters, food (diet), water, infections, and inefficient physical activities, have been summarized. The associations between climate change and modifiable risk factors have no doubt expanded the inequities. People who face overlapping modifiable risk factors, but who are unable to change or adapt, are at the highest risk in the climate change-cancer linkage. Though individual actions to avoid exposure to modifiable risk factors have been recommended, limited benefits would be achieved unless the nations strive to ensure the basic needs of the people. No choice makes avoiding exposure to risk factors an empty phrase. Thus, government actions should be taken to reduce the expanded inequities in cancer risks.

1378The effect of vitamin D supplementation on acute respiratory infection -analysis of the D-Health Trial

Background

Observational studies link vitamin D deficiency with acute respiratory tract infection (ARTI) but results from randomised controlled trials are heterogeneous.

Methods

We used data from The D-Health Trial (N = 21,315); ARTI was a pre-specified trial outcome. Participants were men and women aged 60 to 79 years (with volunteers aged up to 84 years), supplemented with monthly doses of 60,000 international units of vitamin D and followed for up to 5 years. Participants were asked to report occurrence of ARTI over the previous month via annual surveys, and a subset of participants completed 8-week respiratory symptom diaries in winter. We used regression models to estimate odds ratios, rate ratios and rate differences.

Results

Vitamin D supplementation did not reduce the risk of ARTI (survey OR 0.98, 95% CI 0.93 to 1.02; diary OR 0.98, 95% CI 0.83 to 1.15). Analyses of diary data showed that vitamin D reduced the average duration by 0.5 days (95% CI 0.2 to 0.7 days) and the average number of days with severe symptoms by 0.4 days (95% CI 0.3 to 0.6 days).

Conclusions

Monthly bolus doses of 60,000 IU of vitamin D did not reduce the overall risk of ARTI but slightly reduce the duration of symptoms in the general population.

Key messages

The reduction in the duration of symptoms suggests a potential impact of vitamin D on the immune response to infection.

County-level variation in the long-term association between PM2.5 and lung cancer mortality in China

INTRODUCTION

The relative risk (RR) of long-term exposure to PM_2.5 in lung cancer mortality (LCM) may vary spatially in China. However, previous studies applying global regression have been unable to capture such variation. We aimed to employ a geographically weighted Poisson regression (GWPR) to estimate the RRs of LCM among the elderly (≥65 years) related to long-term exposure to PM_2.5 and the LCM attributable to PM_2.5 at the county level in China.

METHODS

We obtained annual LCM in the elderly between 2013 and 2015 from the National Death Surveillance. We linked annual mean concentrations of PM_2.5 between 2000 and 2004 with LCM using GWPR model at 148 counties across mainland China, adjusting for smoking and socioeconomic covariates. We used county-specific GWPR models to estimate annual average LCM in the elderly between 2013 and 2015 attributable to PM_2.5 exposure between 2000 and 2004.

RESULTS

The magnitude of the association between long-term exposure to PM_2.5 and LCM varied with county. The median of county-specific RRs of LCM among elderly men and women was 1.52 (range: 0.90, 2.40) and 1.49 (range: 0.88, 2.56) for each 10 μg/m³ increment in PM_2.5, respectively. The RRs were positively significant (P < 0.05) at 95% (140/148) of counties among both elderly men and women. Higher RRs of PM_2.5 among elderly men were located at Southwest and South China, and higher RRs among elderly women were located at Northwest, Southwest, and South China. There were 99,967 and 54,457 lung cancer deaths among elderly men and women that could be attributed to PM_2.5, with the attributable fractions of 31.4% and 33.8%, respectively.

CONCLUSIONS

The relative importance of long-term exposure to PM_2.5 in LCM differed by county. The results could help the government design tailored and efficient interventions. More stringent PM_2.5 control is urgently needed to reduce LCM in China.

Parametric human modelling to determine body surface area covered by sun-protective clothing

Solar ultraviolet radiation (UVR) is the main environmental risk-factor for cancer of the skin. Sun-protective clothing provides a physical barrier that reduces the UVR dose reaching the skin and European and Australian standards for sun-protective clothing set minimum clothing coverage requirements. Body Surface Area Coverage by clothing (BSAC) is calculated by means of indirect or direct methods, which are laborious and do not support computer-based apparel design. To support the sun-safe specification and design of garments, parametric digital human models and protective clothing mesh covering the minimum Body Surface Area specified in AS/NZS 4399:2017, were created making use of MakeHuman v1.1.1 and Blender software. The Whole Body Surface Area (WBSA) and the BSAC were calculated employing code developed in Blender. Thus, different groups of subjects were analysed to explore BSAC. The method assists in the evaluation of exposed body areas in a wider spectrum of different occupations. Practitioner summary: Sun-protective clothing provides a physical barrier that reduces the UVR dose reaching the skin's surface. Body Surface Area Coverage (BSAC) by clothing is an important determinant of the sun protective capabilities of a garment. In this study, BSAC is calculated using parametric digital human modelling. Abbreviation: UVR: (Solar) ultraviolet radiation; DHM: digital human modeling; BSA: body surface area; BSAC: body surface area coverage (by clothing); BSANC: body surface area not covered (by clothing); WBSA: whole body surface area; BCC: basal cell carcinoma; SCC: squamous cell carcinoma; UPF: ultraviolet protection factor; GPF: garment protection factor.

Multiple interaction nodes define the postreplication repair response to UV-induced DNA damage that is defective in melanomas and correlated with UV signature mutation load

Ultraviolet radiation‐induced DNA mutations are a primary environmental driver of melanoma. The reason for this very high level of unrepaired DNA lesions leading to these mutations is still poorly understood. The primary DNA repair mechanism for UV‐induced lesions, that is, the nucleotide excision repair pathway, appears intact in most melanomas. We have previously reported a postreplication repair mechanism that is commonly defective in melanoma cell lines. Here we have used a genome‐wide approach to identify the components of this postreplication repair mechanism. We have used differential transcript polysome loading to identify transcripts that are associated with UV response, and then functionally assessed these to identify novel components of this repair and cell cycle checkpoint network. We have identified multiple interaction nodes, including global genomic nucleotide excision repair and homologous recombination repair, and previously unexpected MASTL pathway, as components of the response. Finally, we have used bioinformatics to assess the contribution of dysregulated expression of these pathways to the UV signature mutation load of a large melanoma cohort. We show that dysregulation of the pathway, especially the DNA damage repair components, are significant contributors to UV mutation load, and that dysregulation of the MASTL pathway appears to be a significant contributor to high UV signature mutation load.

Short-term association between ambient air pollution and lung cancer mortality

RATIONALE

Long-term exposure to air pollution has been associated with increased lung cancer incidence and mortality. However, the short-term association between air pollution and lung cancer mortality (LCM) remains largely unknown.

METHODS

We collected daily data on particulate matter with diameter <2.5 μm (PM_2.5), particulate matter with diameter < 10 μm (PM₁₀), sulfur dioxide (SO₂), and ozone (O₃), and LCM in three of the biggest cities in China, i.e. Beijing, Chongqing, and Guangzhou, from 2013 to 2015. We first estimated city-specific relationships between air pollutants and LCM using time-series generalized linear models, adjusting for potential confounders. A classification and regression tree (CART) model was used to stratify LCM risk based on combinations of air pollutants and meteorological factors in each city. Then we pooled the city-specific associations using random-effects meta-analysis. Meta regression was used to explore if city-specific characteristics modified the air pollution-LCM association. Finally, we stratified the analyses by season, age, and sex.

RESULTS

Over the entire period, the current-day concentrations of PM_2.5 and PM₁₀ in Chongqing and PM_2.5, PM₁₀, and SO₂ in Guangzhou were positively associated with LCM (Excess risk ranged from 0.72% (95% CI 0.27%-1.17%) to 6.06% (95% CI 0.76%-11.64%) with each 10 μg/m³ increment in different pollutants), but the association between current-day air pollution and LCM in Beijing was not significant (P > 0.05). When considering the environmental and weather factors simultaneously, current-day PM_2.5, relative humidity, and PM₁₀ were the most important factors associated with LCM in Beijing, Chongqing, and Guangzhou, respectively. LCM risk related with daily PM_2.5, PM₁₀, and SO₂ significantly increased with the increasing annual mean temperature and humidity of the city, while LCM risk related with daily O₃ significantly increased with the increases of latitude, annual mean O₃ concentration, and socioeconomic level. After stratification, the current-day PM_2.5, PM₁₀, and O₃ during the warm season in Beijing and PM_2.5, PM₁₀, and SO₂ during the cool season in Chongqing and Guangzhou were positively associated with LCM (Excess risk ranged from 0.93% (95% CI 0.42%-1.45%) to 7.16% (95% CI 0.64%-14.09%) with each 10 μg/m³ increment in different pollutants). Male and the elderly lung cancer patients were more sensitive to the short-term effect of air pollution.

CONCLUSIONS

Lung cancer patients should enhance protection measures against air pollution. More attentions should be paid for the high PM_2.5, PM₁₀, and O₃ during the warm season in Beijing, and high PM_2.5, PM₁₀, and SO₂ during the cool season in Chongqing and Guangzhou.

Lung cancer and particulate pollution: A critical review of spatial and temporal analysis evidence

BACKGROUND

Particulate matter (PM) has been recognized as one of the key risk factors of lung cancer. However, spatial and temporal patterns of this association remain unclear. Spatiotemporal analyses incorporate the spatial and temporal structure of the data within random effects models, generating more accurate evaluations of PM-lung cancer associations at a scale that can better inform lung cancer prevention programs.

METHODS

We conducted a critical review of spatial and temporal analyses of PM and lung cancer. The databases of PubMed, Web of Science and Scopus were searched for potential articles published until September 30, 2017. We included studies that applied spatial and temporal analyses to evaluate the associations of PM_2.5 (inhalable particles with diameters that are 2.5 µm and smaller) and PM₁₀ (inhalable particles with diameters that are 10 µm and smaller) with lung cancer.

RESULTS

We identified 17 articles eligible for the review. Of these, 11 focused on PM_2.5, five on PM₁₀, and one on both. These studies suggested a significant positive association between PM_2.5 exposure and the risk of lung cancer. Relative risks of lung cancer mortality ranged from 1.08 (95% confidence interval (CI): 1.07-1.09) to 1.60 (95%CI: 1.09-2.33) for 10 µg/m³ increase in PM_2.5 exposure. The association between PM₁₀ and lung cancer had been less well researched and the results were not consistent. In terms of the analysis methods, 16 papers undertook spatial analysis and one paper employed temporal analysis. No paper included spatial and temporal analyses simultaneously and considered spatiotemporal uncertainty into model predictions. Among the 16 papers with spatial analyses, thirteen studies presented maps, while only five and 11 studies utilized spatial exploration and modeling methods, respectively.

CONCLUSIONS

Advanced spatial and temporal epidemiological methods were seldom applied to PM-lung cancer associations. Further research is urgently needed to develop and employ robust and comprehensive spatiotemporal analysis methods for the evaluation of PM-lung cancer associations and the support of lung cancer prevention strategies.

The melanoma genomics managing your risk study: A protocol for a randomized controlled trial evaluating the impact of personal genomic risk information on skin cancer prevention behaviors

BACKGROUND

Reducing ultraviolet radiation (UV) exposure and improving early detection may reduce melanoma incidence, mortality and health system costs. This study aims to evaluate the efficacy and cost-effectiveness of providing information on personal genomic risk of melanoma in reducing UV exposure at 12 months, according to low and high traditional risk.

METHODS

In this randomized controlled trial, participants (target sample = 892) will be recruited from the general population, and randomized (1:1 ratio, intervention versus control). Intervention arm participants provide a saliva sample, receive personalized melanoma genomic risk information, a genetic counselor phone call, and an educational booklet on melanoma prevention. Control arm participants receive only the educational booklet. Eligible participants are aged 18-69 years, have European ancestry and no personal history of melanoma. All participants will complete a questionnaire and wear a UV dosimeter to objectively measure their sun exposure at baseline, 1- and 12-month time-points, except 1-month UV dosimetry will be limited to ~250 participants. The primary outcome is total daily Standard Erythemal Doses at 12 months. Secondary outcomes include objectively measured UV exposure for specific time periods (e.g. midday hours), self-reported sun protection and skin-examination behaviors, psycho-social outcomes, and ethical considerations surrounding offering genomic testing at a population level. A within-trial and modelled economic evaluation will be undertaken from an Australian health system perspective to assess the intervention costs and outcomes.

DISCUSSION

This trial will inform the clinical and personal utility of introducing genomic testing into the health system for melanoma prevention and early detection at a population-level.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12617000691347.

The Chinese Children and Families Cohort Study: The Nutrition, Physical Activity, and Ultraviolet Radiation Data Collection

This article reports the study design, methodological issues and early results of a pilot study testing methods for collecting nutrition, physical activity, and ultraviolet (UV) radiation exposure data in a groundbreaking study in China. Epidemiological studies suggest that exposures across the entire life course, including in utero, early childhood, and adolescence, may be important in the etiology of adult cancers and other chronic diseases. The Chinese Children and Families Cohort Study intends to follow-up subjects from the 1993 to 1995 Community Intervention Program of folic acid supplementation for the prevention of neural tube defects. This cohort is unique in that only folic acid exposure during pregnancy varies between groups as other supplements were not available, and there were nutrient deficiencies in the populations. Prior to launching a large-scale follow-up effort, a pilot study was conducted to assess the feasibility of recontacting original study participants to collect extensive diet, physical activity, and UV radiation exposure data in this population. The pilot study included 92 mothers and 184 adolescent children aged 14 to 17 years from 1 urban and 1 rural Community Intervention Program site. Subjects completed a Food Frequency Questionnaire, a 3-day food record, a physical activity questionnaire, a 3-day sun exposure diary together with 3 days of personal UV dosimetry, and 7 days of pedometry measurements and provided blood, saliva, and toenail samples. Grip strength and body composition measurements were taken, and ambient solar UV radiation was monitored in both study sites. While most of the assessments were successful, future studies would likely require different dietary intake instruments. The purpose of this report is to describe the study design and methodological issues emerging from this pilot work relevant for the follow-up of this large birth cohort.

Germ Cell Testicular Cancer Incidence, Latitude and Sunlight Associations in the United States and Australia

International patterns suggest germ cell testicular cancer (GCTC) incidence may be lower in lower latitudes. To investigate this possibility, we examined GCTC incidence by latitude (population centroid in 2000) for men ≥15 years within two reasonably homogeneous countries, the United States and Australia. In the United States, we examined age-adjusted incidence/latitude trends using data from states (2001-2010) and local-area registries (1980-2011). In Australia, we evaluated incidence/latitude trends in 61 Statistical Divisions (2000-2009). In U.S. White men (68 566 cases), state incidences increased by latitude, rising 5.74% (4.45-7.05%) per 5°North latitude increment. Similar trends were found for seminoma and nonseminoma subtypes (P < 0.001). In U.S. Black men (2256 cases), the association was also seen (4.9%; 0.2-9.7%). In local U.S. data, similar increases in incidence with latitude were present in each of the last three decades. In Australia (6042 cases), the incidence increased by 4.43% (95% CI: 1.54-7.39%) per 5°South, and trends for subtypes were similar. Thus, we found that incidence of GCTC in both White and Black men increased significantly with distance from the equator, approximately 1% per degree within the range of latitudes studied.

Outdoor workers and sun protection strategies: two case study examples in Queensland, Australia

INTRODUCTION

Outdoor workers are at risk of developing skin cancer because they are exposed to high levels of harmful ultraviolet radiation. The Outdoor Workers Sun Protection Project investigated sun protection strategies for high risk outdoor workers in rural and regional Australia.

METHODS

Fourteen workplaces (recruitment rate 37%) across four industries in rural and regional Queensland, Australia were recruited to the OWSPP. In 2011-2012, data were collected using pre- and post-intervention interviews and discussion groups. This article presents two workplaces as case study examples.

RESULTS

The flat organisational structure of workplace 1 supported the implementation of the Sun Safety Action Plan (SSAP), whilst the hierarchical organisational nature of workplace 2 delayed implementation of the SSAP. Neither workplace had an existing sun protection policy but both workplaces adopted one. An effect related to the researchers' presence was seen in workplace 1 and to a lesser degree in workplace 2. Overt reciprocity was seen between management and workers in workplace 1 but this was not so evident in workplace 2. In both workplaces, the role of the workplace champion was pivotal to SSAP progression.

CONCLUSIONS

These two case studies highlight a number of contextually bound workplace characteristics related to sun safety. These issues are (1) the structure of workplace, (2) policy, (3) an effect related to the researchers' presence, (4) the workplace champion and (5) reciprocity. There are several recommendations from this article. Workplace health promotion strategies for sun safety need to be contextualised to individual workplaces to take advantage of the strengths of the workplace and to build capacity.

Are the current Australian sun exposure guidelines effective in maintaining adequate levels of 25-hydroxyvitamin D?

An adequate vitamin D status, as measured by serum 25-hydroxyvitamin D (25(OH)D) concentration, is important in humans for maintenance of healthy bones and muscle function. Serum 25(OH)D concentration was assessed in participants from Melbourne, Australia (37.81S, 144.96E), who were provided with the current Australian guidelines on sun exposure for 25(OH)D adequacy (25(OH)D ≥50 nmol/L). Participants were interviewed in February (summer, n=104) and August (winter, n=99) of 2013. Serum 25(OH)D concentration was examined as a function of measures of sun exposure and sun protection habits with control of key characteristics such as dietary intake of vitamin D, body mass index (BMI) and skin colour, that may modify this relationship. The mean 25(OH)D concentration in participants who complied with the current sun exposure guidelines was 67.3 nmol/L in summer and 41.9 nmol/L in winter. At the end of the study, 69.3% of participants who complied with the summer sun exposure guidelines were 25(OH)D adequate, while only 27.6% of participants who complied with the winter sun exposure guidelines were 25(OH)D adequate at the end of the study. The results suggest that the current Australian guidelines for sun exposure for 25(OH)D adequacy are effective for most in summer and ineffective for most in winter. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.

Serum 25-hydroxy vitamin D concentrations are more deficient/insufficient in peritoneal dialysis than haemodialysis patients in a sunny climate

BACKGROUND

Research has identified associations between serum 25(OH)D and a range of clinical outcomes in chronic kidney disease and wider populations. The present study aimed to investigate vitamin D deficiency/insufficiency in dialysis patients and the relationship with vitamin D intake and sun exposure.

METHODS

A cross-sectional study was used. Participants included 30 peritoneal dialysis (PD) (43.3% male; 56.87 ± 16.16 years) and 26 haemodialysis (HD) (80.8% male; 63.58 ± 15.09 years) patients attending a department of renal medicine. Explanatory variables were usual vitamin D intake from diet/supplements (IU day(-1) ) and sun exposure (min day(-1) ). Vitamin D intake, sun exposure and ethnic background were assessed by questionnaire. Weight, malnutrition status and routine biochemistry were also assessed. Data were collected during usual department visits. The main outcome measure was serum 25(OH)D (nm).

RESULTS

Prevalence of inadequate/insufficient vitamin D intake differed between dialysis modality, with 31% and 43% found to be insufficient (<50 nm) and 4% and 33% found to be deficient (<25 nm) in HD and PD patients, respectively (P < 0.001). In HD patients, there was a correlation between diet and supplemental vitamin D intake and 25(OH)D (ρ = 0.84, P < 0.001) and average sun exposure and 25(OH)D (ρ = 0.50, P < 0.02). There were no associations in PD patients. The results remained significant for vitamin D intake after multiple regression, adjusting for age, gender and sun exposure.

CONCLUSIONS

The results highlight a strong association between vitamin D intake and 25(OH)D in HD but not PD patients, with implications for replacement recommendations. The findings indicate that, even in a sunny climate, many dialysis patients are vitamin D deficient, highlighting the need for exploration of determinants and consequences.

A longitudinal study of the impact of chronic psychological stress on health-related quality of life and clinical biomarkers: protocol for the Australian Healthy Aging of Women Study

Background

Despite advancements in our understanding of the importance of stress reduction in achieving good health, we still only have limited insight into the impact of stress on cellular function. Recent studies have suggested that exposure to prolonged psychological stress may alter an individual’s physiological responses, and contribute to morbidity and mortality. This paper presents an overview of the study protocol we are using to examine the impact of life stressors on lifestyle factors, health-related quality of life and novel and established biomarkers of stress in midlife and older Australian women.

The primary aim of this study is to explore the links between chronic psychological stress on both subjective and objective health markers in midlife and older Australian women. The study examines the extent to which exposure frightening, upsetting or stressful events such as natural disasters, illness or death of a relative, miscarriage and relationship conflict is correlated with a variety of objective and subjective health markers.

Methods/Design

This study is embedded within the longitudinal Healthy Aging of Women’s study which has collected data from midlife and older Australian women at 5 yearly intervals since 2001, and uses the Allostastic model of women’s health by Groër and colleagues in 2010. The current study expands the focus of the HOW study and will assess the impact of life stressors on quality of life and clinical biomarkers in midlife and older Australian women to explain the impact of chronic psychological stress in women.

Discussion

The proposed study hypothesizes that women are at increased risk of exposure to multiple or repeated stressors, some being unique to women, and the frequency and chronicity of stressors increases women’s risk of adverse health outcomes. This study aims to further our understanding of the relationships between stressful life experiences, perceived quality of life, stress biomarkers, chronic illness, and health status in women.

Interventions to decrease skin cancer risk in outdoor workers: update to a 2007 systematic review

Background

Outdoor workers are at high risk of harmful ultraviolet radiation exposure and are identified as an at risk group for the development of skin cancer. This systematic evidence based review provides an update to a previous review published in 2007 about interventions for the prevention of skin cancer in outdoor workers.

Results

This review includes interventions published between 2007-2012 and presents findings about sun protection behaviours and/or objective measures of skin cancer risk. Six papers met inclusion criteria and were included in the review. Large studies with extended follow-up times demonstrated the efficacy of educational and multi-component interventions to increase sun protection, with some higher use of personal protective equipment such as sunscreen. However, there is less evidence for the effectiveness of policy or specific intervention components.

Conclusions

Further research aimed at improving overall attitudes towards sun protection in outdoor workers is needed to provide an overarching framework.

Abstract B100: Association between ambient ultraviolet radiation and risk of esophageal cancer

Background and Aims: Ecological studies have suggested an inverse relationship between latitude and risks of some cancers. However, associations between solar ultraviolet radiation (UVR) exposure and esophageal cancer risk have not been fully explored. We therefore investigated the association between nevi, freckles and measures of ambient UVR over the life-course with risks of esophageal cancers.

Methods: We compared estimated lifetime residential ambient UVR among Australian patients with esophageal cancer (330 esophageal adenocarcinoma (EAC), 386 esophago-gastric junction adenocarcinoma (EGJAC), and 279 esophageal squamous cell carcinoma (ESCC)), and 1471 population controls. We asked people where they had lived at different periods of their life, and assigned ambient UVR to each location based on measurements from NASA's Total Ozone Mapping Spectrometer database. Freckling and nevus burden were self-reported. We used multivariable logistic regression models to estimate the magnitude of associations between phenotype, ambient UVR and esophageal cancer risk.

Results: Compared with population controls, patients with EAC and EGJAC were less likely to have high levels of estimated cumulative lifetime ambient UVR (EAC OR 0.59, 95% CI 0.35 – 0.99, EGJAC OR 0.55, 0.34 – 0.90). We found no association between UVR and risk of ESCC (OR 0.91, 0.51 – 1.64). The associations were independent of age, sex, BMI, education, state of recruitment, frequency of reflux, smoking status, alcohol consumption, and H.pylori serostatus. Cases with EAC were also significantly less likely to report high levels of nevi than controls.

Conclusion: These data show an inverse association between ambient solar UVR at residential locations and risk of EAC and EGJAC, but not ESCC.

Citation Format: Bich Tran, Robyn Lucas, Michael Kimlin, David Whiteman, Neale Rachel. Association between ambient ultraviolet radiation and risk of esophageal cancer. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr B100.

Validity and use of the UV index: report from the UVI working group, Schloss Hohenkammer, Germany, 5-7 December 2011

The adequacy of the UV Index (UVI), a simple measure of ambient solar ultraviolet (UV) radiation, has been questioned on the basis of recent scientific data on the importance of vitamin D for human health, the mutagenic capacity of radiation in the UVA wavelength, and limitations in the behavioral impact of the UVI as a public awareness tool. A working group convened by ICNIRP and WHO met to assess whether modifications of the UVI were warranted and to discuss ways of improving its effectiveness as a guide to healthy sun-protective behavior. A UV Index greater than 3 was confirmed as indicating ambient UV levels at which harmful sun exposure and sunburns could occur and hence as the threshold for promoting preventive messages. There is currently insufficient evidence about the quantitative relationship of sun exposure, vitamin D, and human health to include vitamin D considerations in sun protection recommendations. The role of UVA in sunlight-induced dermal immunosuppression and DNA damage was acknowledged, but the contribution of UVA to skin carcinogenesis could not be quantified precisely. As ambient UVA and UVB levels mostly vary in parallel in real life situations, any minor modification of the UVI weighting function with respect to UVA-induced skin cancer would not be expected to have a significant impact on the UV Index. Though it has been shown that the UV Index can raise awareness of the risk of UV radiation to some extent, the UVI does not appear to change attitudes to sun protection or behavior in the way it is presently used. Changes in the UVI itself were not warranted based on these findings, but rather research testing health behavior models, including the roles of self-efficacy and self-affirmation in relation to intention to use sun protection among different susceptible groups, should be carried out to develop more successful strategies toward improving sun protection behavior.

Variations in serum vitamin D status during cancer chemotherapy

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Background: Low serum vitamin D in cancer patients has been associated with inferior cancer outcomes and bone loss. The impact of chemotherapy on vitamin D levels is not known. We examined serum vitamin D levels during chemotherapy to identify magnitude and predictors of change. Methods: A prospective study of chemotherapy naïve patients commencing chemotherapy in two different sun exposure areas. Vitamin D (25(OH)D) deficiency was defined as ≤25 nmol/L and insufficiency 26-50 nmol/L. Demographic data, nutrition, sun exposure, season and biochemical parameters were collected at baseline 6 weeks (6W) and 12 weeks (12W) since commencement of treatment. The effects were assessed using a multivariate multilevel linear regression model that also included age, gender and BMI. Results: 82 Caucasian and 3 indigenous patients were enrolled. Median age was 57 (21-85) years. Forty-nine (58%) were female; 54 (65%) were treated with curative intent. Tumours included 29 (34%) breast,12 (14%) colorectal, 9 (11%) lymphomas, 7 (8%) leukemias, 7 (8%) lung, 5 (6%) ovarian, 3 (4%) testis, 3 (4%) unknown primary and 10 (11%) others. Median weight was 75 kg (50-151) and median BMI was 26.9 kg/m2 (17.7- 44.5). Seventy-six (89%) and 55 (65%) patients were receiving chemotherapy treatment at 6W and 12W respectively. Mean (±SD) serum 25(OH)D at baseline was 49.2±22.3 nmol/L. Ten (12%) patients were vitamin D deficient at baseline and a further 33 (41%) had insufficient levels. Mean serum 25(OH)D status was higher in higher sun exposure locations (61.9±22.1 nmol/L vs 42.2±19.2 nmol/L, p<0.001), varied according to season (spring=46.9±20.3 nmol/L, summer=50.8±18.2 nmol/L, fall=76.4±25.2 nmol/L, winter=36.5±15.7 nmol/L, p<0.001) and changed with treatment period (baseline=49.2±22.3 nmol/L, 6W=40.9±19.0 nmol/L, 12W=45.9±19.7 nmol/L, p=0.002). There was no association between 25(OH)D status and age, gender, BMI or nutritional status. Conclusions: Chemotherapy is associated with a fall in serum 25(OH)D. Further research is needed to determine the underlying mechanism, the impact of low serum 25(OH)D on patient outcomes and the potential role for screening and vitamin D supplementation in this group.

Vitamin D status of adults from tropical Australia determined using two different laboratory assays: implications for public health messages

We measured serum 25 hydroxyvitamin D [25(OH)D] levels of ambulatory adults in tropical Australia to determine whether it is appropriate to continue promoting sun-safety in this population. In August 2006 (winter), self-administered questionnaires were completed by 145 Meals-on-Wheels volunteers (49.3% male; mean age 57.8 ± 14.7 years; 76.6% response) from Townsville, Queensland (Latitude 19(o) S). Serum 25(OH)D was analyzed using two common assays. Mean levels were 68.3 (SD ± 18.7; range 26-142) by DiaSorin Radioimmunoassay and 83.0 (SD ± 30.8; range 30-184) by DiaSorin Liaison® one. No participants were 25(OH)D deficient (<25 nmol L(-1)). Nine participants (6.2%) had 25(OH)D levels between 25 and 50 nmol L(-1) (insufficient), by both methods (seven with a BMI ≥ 25). Twenty-eight participants (19.3%) had one result in the insufficient range and the other in the adequate range. Thus, almost all of these free-living adults in tropical Australia had adequate vitamin D levels at the end of winter. There was poor agreement between the two 25(OH)D assays. These results suggest it is appropriate to continue promoting sun-safe messages to the ambulatory Caucasian adult population of North Queensland, which has an extremely high incidence of skin cancer. The lack of agreement between the two assays is a concern. Few doctors are aware of this measurement issue.

In vitro model of vitamin D synthesis by UV radiation in an Australian urban environment

Vitamin D, an important constituent of human health, is produced through the exposure of human skin to short wave (280-315 nm) ultraviolet radiation (UV). We aimed to establish whether an urbanized environment with tall buildings in close proximity (an "urban canyon") significantly reduced the capacity of sunlight to synthesize vitamin D, when compared with a typical suburban area (∼2.5 km away); and to investigate the association of UV and vitamin D production with pollution, temperature, and humidity. Measurements of ambient UV (295-400 nm) (using a portable photometer/radiometer and detector) and synthesized vitamin D (from an in vitro model) were taken regularly at urban and control sites over 3 months in Brisbane, Australia. During a typical 20 min measurement, urban and control sites received 0.26 and 1.03 W m(-2) mean total UV respectively (P < 0.001), and produced 0.12 and 0.53 μg mL(-1) mean vitamin D (P < 0.001). Pollution, temperature and humidity were not associated with UV or vitamin D production. This demonstrates a large difference in vitamin D synthesis between an urban canyon and a nearby control site. Although the results cannot be directly applied to humans, they emphasize the need for further study of human vitamin D production in urban environments.

Sun protection and low levels of vitamin D: are people concerned?

OBJECTIVE

Recent reports on the association between low serum vitamin D and increased risk of cancer raised concerns about possible adverse effects of primary prevention strategies for skin cancer. To evaluate if these reports may influence peoples' sun protective behavior, knowledge, and attitudes to the impact of sun protection on vitamin D.

METHODS

Within a population-based survey in Queensland, Australia (5,611 participants, mean age 50.7 years (range 20-75); 48.2% men), agreement with the statement that sun protection may result in not having enough vitamin D as well as factors associated with agreement were assessed.

RESULTS

Overall, 837 (15.0%) participants agreed that sun protection may result in not having enough vitamin D, 2,163 (38.7%) neither agreed nor disagreed, and 2,591 (46.3%) disagreed with this statement. Factors associated with agreement included older age, darker skin color, and attempt to develop a suntan within the past year.

CONCLUSION

These results suggest that future sun protection campaigns may need to address the issue of vitamin D and present ways to achieve sufficient vitamin D levels without increasing sun exposure at least in countries with high UV radiation throughout the year.

Hypothesis: hair cover can protect against invasive melanoma on the head and neck (Australia)

The anatomic distribution of cutaneous melanoma reflects people's levels and patterns of sun exposure. While examining trends of incident invasive melanomas by site in recent decades in Australia we noted significant increases in incidence on the ears but not the face or any other site in women younger than 40 years, by 6% (95% confidence interval [CI] 2-10%) per year, and 40-59 years by 7% (95% CI 4-10%) per year. Men of the same age showed no corresponding changes in ear melanoma. However incidence rates of ear melanoma in general were fourfold higher in males than females in Australia. Further, using data from the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) Program, rates of invasive melanoma on the ear were found to be sevenfold higher in males than females in the US population in the same period. Higher rates of scalp and neck melanomas were also seen in men and women in both populations. We therefore speculated that the isolated rises of ear melanoma in younger women in Australia, and the higher overall rates of ear, scalp and neck melanoma in men compared with women, reflect differences in hair coverage. We tested the specific hypothesis that hair cover reduces sun exposure of the ears using experimental manikins and found that hair cover of the ear reduced solar ultraviolet-B exposure by 81% [SE +/-8] compared with uncovered ears. We conclude that hair cover can protect against invasive melanoma on the ear and may similarly protect on the scalp and neck. When discretionary, hair may be an important additional factor to be considered for melanoma prevention.

Usage of real-time ultraviolet radiation data to modify the daily erythemal exposure of primary schoolchildren

BACKGROUND/AIMS

Primary schoolchildren in their everyday school life are exposed to solar ultraviolet radiation. This may be through time spent outdoors whilst having meal breaks, physical education classes and other class orientated outdoor activities.

METHODS

This research investigates the UV exposure of primary schoolchildren and the effect real-time UV irradiances data and an associated software package, UVGUIDE, have on UV exposure. This software utilises scientifically collected data, such as facial distribution of UV, as well as accessing real-time on-line UV irradiances data to estimate the UV distribution to the head region. The students can also enter other parameters such as hat usage and hat type to show the effect of using such a UV protective device on their facial UV distribution.

CONCLUSIONS

The results from this study found that the average 3-day erythemal UV exposure in late summer and early autumn to the left shoulder was 33% higher for the students not having access to the on-line UV data and software package.