How many melanomas might be prevented if more people applied sunscreen regularly?

Skin Cancer Knowledge, Sun Exposure, Photoprotection Behavior, and Perceived Barriers Associated with Skin Cancer Types in a Greek Cohort: A Cross-Sectional Study on the Island of Crete

BACKGORUND

This study aimed to explore the relationship between different types of skin cancer and factors such as sun exposure and photoprotection measures in a Greek cohort on the island of Crete.

METHODS

This cross-sectional observational study was conducted in the Dermatology Department of the University Hospital in Heraklion, Crete, between January 2019 and January 2024. The study population included consecutive patients diagnosed with basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and malignant melanoma (MM), as well as healthy controls. The participants completed a self-reported questionnaire covering demographic and clinical data as well as questions about sun exposure and photoprotection habits.

RESULTS

A total of 265 skin cancer patients and 106 healthy controls participated in the study: 50.6% of the patients had basal cell carcinoma, 35.1% had squamous cell carcinoma, and 14.3% had malignant melanoma. The cohort comprised 41.5% females and 58.5% males, with a mean age of 73.2 years. As expected, the patients with skin cancer had a lighter skin phototype compared to the healthy controls (p < 0.01). They also reported greater occupational (p < 0.01) and leisure sun exposure (p < 0.01) and a higher median number of vacation weeks spent outdoors before the age of 18 (p = 0.030). Furthermore, the healthy controls were more likely to use sunscreen (p = 0.035) and preferred higher SPF (>50) when they did so (p < 0.01). The healthy controls also reported more frequent use of sunglasses (p < 0.01), brimmed hats (p < 0.01), and long-sleeved clothing (p < 0.01) compared to the skin cancer patients.

CONCLUSION

This is the first study to analyze sun exposure and photoprotection behaviors in patients with nonmelanoma skin cancer (NMSC) and malignant melanoma (MM) in Crete, revealing the key associations and underscoring the need for targeted prevention strategies.

Artificial Intelligence-Driven Skin Aging Simulation as a Novel Skin Cancer Prevention

INTRODUCTION

Skin cancer, a prevalent cancer type among fair-skinned patients globally, poses a relevant public health concern due to rising incidence rates. Ultraviolet (UV) radiation poses a major risk factor for skin cancer. However, intentional tanning associated with sunburns remains a common practice, notably among female adults. Appropriate prevention campaigns targeting children and adolescents are needed to improve sun protection behavior particularly in these age groups. The aim of our study was to investigate if an AI-based simulation of facial skin aging can enhance sun protection behavior in female adults.

METHODS

In this single-center, prospective, observational pilot study at Department of Dermatology at the University Hospital of Basel, we took photographs of healthy young females' faces with a VISIA-CR camera (Version 8.2; Canfield Scientific Inc., Parsippany, NJ, USA) between February and March 2021. Digital images were performed in three angles (straight, left 45°, and right 45°). All participants received an AI-based simulation of their facial skin with continuous aging to 80 years. A newly created anonymous questionnaire capturing participants' sociodemographic data and also tanning and sun protection behavior was completed in pre- and post-aging simulation. To observe long-term effects, a 2-year follow-up was conducted between March and April 2023.

RESULTS

The 60 participants (mean age 23.6 ± 2.5 years) evaluated the importance of sun protection significantly higher after skin aging simulation with VISIA-CR camera (p < 0.0001; 95% CI: 8.2-8.8). Post-intervention, 91.7% (55/60) of the females were motivated to reduce UV exposure and to intensify UV protection in the future since the individual UV-dependent risk was perceived significantly higher (p < 0.001; 95% CI: 5.9-6.7). At 2-year follow-up, 96% (24/25) indicated persistent effort reducing UV exposure. The preference for SPF 50+ sunscreen increased to 46.7% (28/65) directly after the skin aging simulation and continued to rise up to 60.0% (15/25) after 2 years.

CONCLUSIONS

Our data emphasize the potential of AI-assisted photoaging interventions to enhance motivation for UV protection in the short and the long term. We encourage that different age and gender groups are addressed in a personalized, generation-specific manner with the appropriate media and by considering the Hawthorne effect. Campaigns with visual AI support can improve the intent of cancer-preventative behavior.

INTRODUCTION

Skin cancer, a prevalent cancer type among fair-skinned patients globally, poses a relevant public health concern due to rising incidence rates. Ultraviolet (UV) radiation poses a major risk factor for skin cancer. However, intentional tanning associated with sunburns remains a common practice, notably among female adults. Appropriate prevention campaigns targeting children and adolescents are needed to improve sun protection behavior particularly in these age groups. The aim of our study was to investigate if an AI-based simulation of facial skin aging can enhance sun protection behavior in female adults.

METHODS

In this single-center, prospective, observational pilot study at Department of Dermatology at the University Hospital of Basel, we took photographs of healthy young females' faces with a VISIA-CR camera (Version 8.2; Canfield Scientific Inc., Parsippany, NJ, USA) between February and March 2021. Digital images were performed in three angles (straight, left 45°, and right 45°). All participants received an AI-based simulation of their facial skin with continuous aging to 80 years. A newly created anonymous questionnaire capturing participants' sociodemographic data and also tanning and sun protection behavior was completed in pre- and post-aging simulation. To observe long-term effects, a 2-year follow-up was conducted between March and April 2023.

RESULTS

The 60 participants (mean age 23.6 ± 2.5 years) evaluated the importance of sun protection significantly higher after skin aging simulation with VISIA-CR camera (p < 0.0001; 95% CI: 8.2-8.8). Post-intervention, 91.7% (55/60) of the females were motivated to reduce UV exposure and to intensify UV protection in the future since the individual UV-dependent risk was perceived significantly higher (p < 0.001; 95% CI: 5.9-6.7). At 2-year follow-up, 96% (24/25) indicated persistent effort reducing UV exposure. The preference for SPF 50+ sunscreen increased to 46.7% (28/65) directly after the skin aging simulation and continued to rise up to 60.0% (15/25) after 2 years.

CONCLUSIONS

Our data emphasize the potential of AI-assisted photoaging interventions to enhance motivation for UV protection in the short and the long term. We encourage that different age and gender groups are addressed in a personalized, generation-specific manner with the appropriate media and by considering the Hawthorne effect. Campaigns with visual AI support can improve the intent of cancer-preventative behavior.

Predicted Cervical Cancer Prevention: Impact of National HPV Vaccination Program on Young Women in South Korea

PURPOSE

This study aimed to evaluate the effectiveness of the national human papillomavirus (HPV) vaccination program of South Korea among its entire female population, particularly among younger age groups.

MATERIALS AND METHODS

We first predicted the incidence of cervical cancer over the next 20 years (2021-2040) using the Nordpred package based on Møller's age-period-cohort model under several scenarios for the national HPV vaccination program. We calculated the potential impact fractions and proportional differences under the current national vaccination programs, and alternative scenarios using the no-vaccination assumption as a reference.

RESULTS

We estimated that the current national vaccination program would prevent 4.13% of cervical cancer cases and reduce the age-standardized incidence rate (ASR) by 8.79% in the overall population by 2036-2040. Under the alternative scenario of implementing the nine-valent vaccine, 5.13% of cervical cancer cases could be prevented and the ASR reduced by 10.93% during the same period. In another scenario, expanding the vaccination age to 9-17 years could prevent 10.19% of cervical cancer cases, with the ASR reduced by 18.57% during the same period. When restricted to ages < 40 years, the prevention effect was remarkably greater. We predict that the current national HPV program will reduce its incidence by more than 30% between 2036 and 2040 in women aged < 40 years.

CONCLUSION

The effectiveness of the vaccination program in reducing the incidence of cervical cancer was confirmed, with a considerable impact anticipated in younger age groups.

In vitro safety evaluation of (6-methoxy-9-oxo-9H-xanthen-2-yl)methyl (E)-3-(2,4-dimethoxyphenyl)acrylate (K-116) - the novel potential UV filter designed by means of a double chromophore strategy

The use of topical photoprotection is necessary to reduce adverse effects caused by excessive exposure to ultraviolet radiation. Despite the high standards set for UV filters, many of them may contribute to the occurrence of adverse effects. The newly synthesised compound K-116, the (E)-cinnamoyl xanthone derivative, could be an alternative. We conducted extended in vitro safety evaluation of compound K-116. The research included assessment of irritation potential on skin tissue, evaluation of penetration through the epidermis, and assessment of phototoxicity, and mutagenicity. Additionally, the eco-safety of compound K-116 was evaluated, including an examination of its degradation pathway in the Cunninghamella echinulata model, as well as in silico simulation of the toxicity of both the parent compound and its degradation products. The research showed that compound K-116 tested in future application conditions is deprived of skin irritant potential additionally it does not penetrate through the epidermis. Results showed that K-116 concentrate is not phototoxic and not mutagenic. The eco-safety studies showed that it undergoes biodegradation in 27% in Cunninghamella echinulata model. The parent compound and formed metabolite are less toxic than reference UV filters (octinoxate and octocrylene).

The adverse consequences of not using sunscreens

The adverse effects of solar ultraviolet radiation (UVR) on normal skin are well established, especially in those with poorly melanized skin. Clinically, these effects may be classified as acute, such as erythema or chronic such as keratinocyte and melanocyte skin cancers. Apart from skin type genetics, clinical responses to solar UVR are dependent on geophysical (e.g., solar intensity) and behavioural factors. The latter are especially important because they may result in 'solar overload' with unwanted clinical consequences and ever greater burdens to healthcare systems. Correctly used, sunscreens can mitigate the acute and chronic effects of solar UVR exposure. Laboratory studies also show that sunscreens can inhibit the initial molecular and cellular events that are responsible for clinical outcomes. Despite public health campaigns, global trends continue to show increasing incidence of all types of skin cancer. Large-scale epidemiological studies have shown the benefits of sunscreen use in preventing skin cancer, though it is likely that sunscreen use has not been optimal in such studies. It is evident that without substantial changes in sun-seeking behaviour, sunscreen use is a very important part of the defence against the acute and chronic effects of solar exposure. Ideally, sunscreens should be able to provide the level of protection that reduces the risk of skin cancer in susceptible skin types to that observed in heavily melanized skin.

Longitudinal comparisons of self-affirmation approaches for sun protection

OBJECTIVES

Self-affirmation approaches for health behaviour demonstrate consistent small to medium effects on message acceptance, health intentions and behaviour change. There are several forms of self-affirmation (e.g., values affirmations, implementation intentions), but few empirical comparisons to guide selection in empirical work. Further, there has been little emphasis on the putative mechanisms of self-affirmation driving behaviour change. The current investigation compared a control and four self-affirmation approaches: values, social, implementation intention, and perspective taking.

METHODS

Participants were recruited through CloudResearch (N = 666) and reported baseline sun exposure and protection behaviour at Time 1. One week later (Time 2), returning participants (N = 535) were randomly assigned to condition, viewed a message conveying risks of sun exposure, and reported sun exposure and protection intentions for the next week. Follow-up one week later (Time 3; N = 449) assessed past week sun exposure (i.e., number of days spent outside during peak hours), sun protection behaviour (e.g., sunscreen use), future sun exposure and protection intentions and engagement with resources conveying further health information (i.e., viewing infographics, following links to websites with more information). The association of putative mechanisms with self-affirmation conditions and health outcomes was also examined.

RESULTS

Unexpectedly, there were few differences between self-affirmation conditions and the control on intentions, information seeking, or behaviour at follow-up. At follow-up, perspective circle participants reported fewer days spent outside, spent longer viewing infographics, and, along with social values participants, followed more weblinks seeking information than control participants. The putative mechanisms were unrelated to health outcomes.

CONCLUSIONS

The current investigation was a first step in comparing novel online self-affirmation approaches and had largely null findings. Results suggest that the perspective circle performed best at promoting information seeking and, to some extent, behaviour change. Suggestions for future directions are discussed.

Patterns of Sun Protection Behaviours among Australian Adolescents and Adults over a Six-Year Period

The major cause for skin cancer is the excessive and unprotected exposure to ultraviolet radiation (UVR), which can be prevented by engaging in sun protection behaviours. As longitudinal studies on both adolescents' and adults' performances of sun protection behaviours are limited, the current study aimed to investigate changes in sun protection in these population segments in Western Australia, a region with high annual UVR. During six summer seasons (2015/16 to 2020/21), cross-sectional surveys were conducted among 1806 adolescents (14 to 17 years old) and 1808 adults (18-45 years old), investigating the frequency of five sun protection behaviours (wearing clothing, applying sunscreen, wearing a hat, wearing sunglasses, and seeking shade) and sun avoidance (staying indoors). Over the six-year period, staying indoors increased in both groups. Among adolescents, a decrease in wearing clothing and sunglasses and an increase in seeking shade was demonstrated, and hat and sunscreen use remained relatively stable. Among adults, an increase in sunscreen use was shown, whereas all other sun-related behaviours remained consistent over the six-year period. The results from this study can provide directions for health communications focusing on improving sun protection behaviours among both adolescent and adult populations.

Development of a Survey of Sunscreen Use and Attitudes among Adults in Two Coastal States, 2019

Skin cancer is the most common form of cancer in the United States, and regular use of broad-spectrum sunscreens can prevent skin cancer. However, a new law in Hawaii that limits sunscreen choices due to the belief that some UV (ultraviolet) filters may damage coral reefs may reduce sunscreen use and increase skin-cancer risk. Because of this, there is a need for measurement tools to help understand consumer behavior and determinants of sunscreen purchase and use. The objectives of this study were (1) to test new questionnaire measures relevant to the Hawaii Sunscreen Ban; and (2) to assess adults’ knowledge, attitudes, and habits related to sunscreen in two other coastal states. This survey of adult residents of California and Florida was conducted in the summer of 2019. Newly developed scales addressed beliefs about effects of sunscreens on aquatic/marine environments and awareness of the Hawaii sunscreen ban. Respondents completed the survey twice to evaluate the test–retest reliability. Respondents (n = 162) were mainly female, White, and college-educated. New scales had moderate-to-high internal consistency and high test–retest reliability. Sunscreen use was high, sunburn was common, and knowledge and attitudes about sunscreen were modest. Most respondents did not know the specifics of the Hawaii Sunscreen Ban. In multivariate models, significant predictors of sunscreen use were being older, female, and having higher sunscreen knowledge. Sunscreen beliefs were not significantly associated with sunscreen use or sunburn. The findings support the use of the newly developed survey and suggest that more education about sunscreen and sunscreen ingredients is needed.

Etiologies of Melanoma Development and Prevention Measures: A Review of the Current Evidence

Simple Summary

Melanoma constitutes a major public health risk, with the rates of diagnosis increasing on a yearly basis. Monitoring for risk factors and preventing dangerous behaviors that increase melanoma risk, such as tanning, are important measures for melanoma prevention. Additionally, assessing the effectiveness of various methods to prevent sun exposure and sunburns—which can lead to melanoma—is important to help identify ways to reduce the development of melanoma. We summarize the recent evidence regarding the heritable and behavioral risks underlying melanoma, as well as the current methods used to reduce the risk of developing melanoma and to improve the diagnosis of this disease.

Abstract

(1) Melanoma is the most aggressive dermatologic malignancy, with an estimated 106,110 new cases to be diagnosed in 2021. The annual incidence rates continue to climb, which underscores the critical importance of improving the methods to prevent this disease. The interventions to assist with melanoma prevention vary and typically include measures such as UV avoidance and the use of protective clothing, sunscreen, and other chemopreventive agents. However, the evidence is mixed surrounding the use of these and other interventions. This review discusses the heritable etiologies underlying melanoma development before delving into the data surrounding the preventive methods highlighted above. (2) A comprehensive literature review was performed to identify the clinical trials, observational studies, and meta-analyses pertinent to melanoma prevention and incidence. Online resources were queried to identify epidemiologic and clinical trial information. (3) Evidence exists to support population-wide screening programs, the proper use of sunscreen, and community-targeted measures in the prevention of melanoma. Clinical evidence for the majority of the proposed preventive chemotherapeutics is presently minimal but continues to evolve. (4) Further study of these chemotherapeutics, as well as improvement of techniques in artificial intelligence and imaging techniques for melanoma screening, is warranted for continued improvement of melanoma prevention.

Effect of a Face-Aging Mobile App-Based Intervention on Skin Cancer Protection Behavior in Secondary Schools in Brazil: A Cluster-Randomized Clinical Trial

Question

Can a face-aging mobile app improve the skin cancer protection behavior of secondary school students?

Findings

In this cluster-randomized clinical trial of 52 school classes with 1573 Brazilian pupils, meaningful improvements were observed in sunscreen use, tanning behavior, and skin self-examinations 3 to 6 months after an intervention using a face-aging app compared with the nonintervention group.

Meaning

Face-aging apps may be useful tools to increase skin cancer protection in adolescents and thereby decrease skin cancer risk.

Importance

Because exposure to UV radiation early in life is an important risk factor for melanoma development, reducing UV exposure in children and adolescents is of paramount importance. New interventions are urgently required.

Objective

To determine the effect of the free face-aging mobile app Sunface on the skin cancer protection behavior of adolescents.

Design, Setting, and Participants

This cluster-randomized clinical trial included a single intervention and a 6-month follow-up from February 1 to November 30, 2018. Randomization was performed on the class level in 52 school classes within 8 public secondary schools (grades 9-12) in Itauna, Southeast Brazil. Data were analyzed from May 1 to October 10, 2019.

Interventions

In a classroom seminar delivered by medical students, adolescents’ selfies were altered by the app to show UV effects on their future faces and were shown in front of their class, accompanied by information about UV protection. Information about relevant parameters was collected via anonymous questionnaires before and 3 and 6 months after the intervention.

Main Outcomes and Measures

The primary end point of the study was the difference in daily sunscreen use at 6 months of follow-up. Secondary end points included the difference in daily sunscreen use at 3 months of follow-up, at least 1 skin self-examination within 6 months, and at least 1 tanning session in the preceding 30 days. All analyses were predefined and based on intention to treat. Cluster effects were taken into account.

Results

Participants included 1573 pupils (812 girls [51.6%] and 761 boys [48.4%]; mean [SD] age, 15.9 [1.3] years) from 52 school classes. Daily sunscreen use increased from 110 of 734 pupils (15.0%) to 139 of 607 (22.9%; P < .001) at the 6-month follow-up in the intervention group. The proportion of pupils performing at least 1 skin self-examination in the intervention group rose from 184 of 734 (25.1%) to 300 of 607 (49.4%; P < .001). Use of tanning decreased from 138 of 734 pupils (18.8%) to 92 of 607 (15.2%; P = .04). No significant changes were observed in the control group. The intervention was more effective for female students (number needed to treat for the primary end point: 8 for girls and 31 for boys).

Conclusions and Relevance

These findings suggest that interventions based on face-aging apps may increase skin cancer protection behavior in Brazilian adolescents. Further studies are required to maximize the effect and to investigate the generalizability of the effects.

Trial Registration

ClinicalTrials.gov Identifier: NCT03178240

Sustainable effect of individualised sun protection advice on sun protection behaviour: a 10-year follow-up of a randomised controlled study in primary care

Background

In the light of increasing skin cancer incidences worldwide, preventive measures to promote sun protection in individuals with risky sun habits have continued relevance and importance.

Aim

To report the long-term effect of individualised sun protection advice given in primary health care (PHC), on sun habits and sun protection behaviour.

Design & setting

In 2005, 309 PHC patients were enrolled in a randomised controlled study performed in a Swedish PHC setting.

Method

At baseline, the study participants completed a Likert scale-based questionnaire, mapping sun habits, propensity to increase sun protection, and attitudes towards sun exposure, followed by randomisation into three intervention groups, all receiving individualised sun protection advice: in Group 1 (n = 116) by means of a letter, and in Group 2 (n = 97) and 3 (n = 96) communicated personally by a GP. In Group 3, participants also underwent a skin ultraviolet-sensitivity phototest, with adjusted sun protection advice based on the result. A repeated questionnaire was administered after 3 and 10 years.

Results

Statistically significant declines were observed in all groups for sun exposure mean scores over time. When using a cumulative score, according to the Sun Exposure and Protection Index (SEPI), significantly greater decrease in SEPI mean score was observed in Groups 2 and 3 (GP), compared to Group 1 (letter); P<0.01. The addition of a phototest did not enhance the effect of the intervention.

Conclusion

Individualised sun protection advice mediated verbally by the GP can lead to sustained improvement of sun protective behaviour.

Examine all available evidence before making decisions on sunscreen ingredient bans

Coral bleaching is a worldwide problem and more needs to be done to determine causes and potential solutions. A myopic focus on sunscreen ingredients as the proximate cause of coral bleaching provides consumers a false belief that enacted bans of these ingredients will erase decades of coral reef decline. Instead, these bans will likely only lead to decreased sunscreen use and exposure to potentially harmful UV radiation. A closer examination of all available evidence on the causes of coral reef bleaching needs to be undertaken, including a more thorough appraisal of studies conducted under artificial conditions using higher concentrations of sunscreen ingredients.

The effect of sunscreen on vitamin D: a review

BACKGROUND

Sunscreen use can prevent skin cancer, but there are concerns that it may increase the risk of vitamin D deficiency.

OBJECTIVES

We aimed to review the literature to investigate associations between sunscreen use and vitamin D₃ or 25 hydroxyvitamin D [25(OH)D] concentration.

METHODS

We systematically reviewed the literature following the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines. We identified manuscripts published in English between 1970 and 21 November 2017. Eligible studies were experimental [using an artificial ultraviolet radiation (UVR) source], field trials or observational studies. The results of each of the experimental studies and field trials are described in detail. Two authors extracted information from observational studies, and applied quality scoring criteria that were developed specifically for this question. These have been synthesized qualitatively.

RESULTS

We included four experimental studies, three field trials (two were randomized controlled trials) and 69 observational studies. In the experimental studies sunscreen use considerably abrogated the vitamin D₃ or 25(OH)D production induced by exposure to artificially generated UVR. The randomized controlled field trials found no effect of daily sunscreen application, but the sunscreens used had moderate protection [sun protection factor SPF) ~16]. The observational studies mostly found no association or that self-reported sunscreen use was associated with higher 25(OH)D concentration.

CONCLUSIONS

There is little evidence that sunscreen decreases 25(OH)D concentration when used in real-life settings, suggesting that concerns about vitamin D should not negate skin cancer prevention advice. However, there have been no trials of the high-SPF sunscreens that are now widely recommended. What's already known about this topic? Previous experimental studies suggest that sunscreen can block vitamin D production in the skin but use artificially generated ultraviolet radiation with a spectral output unlike that seen in terrestrial sunlight. Nonsystematic reviews of observational studies suggest that use in real life does not cause vitamin D deficiency. What does this study add? This study systematically reviewed all experimental studies, field trials and observational studies for the first time. While the experimental studies support the theoretical risk that sunscreen use may affect vitamin D, the weight of evidence from field trials and observational studies suggests that the risk is low. We highlight the lack of adequate evidence regarding use of the very high sun protection factor sunscreens that are now recommended and widely used.

Challenges in assessing the sunscreen-melanoma association

Whether sunscreen use affects melanoma risk has been widely studied with contradictory results. To answer this question we performed a systematic review of all published studies, accounting for sources of heterogeneity and bias. We searched for original articles investigating the sunscreen-melanoma association in humans to February 28, 2018. We then used random-effects meta-analysis to combine estimates of the association, stratified by study design. Stratified meta-analysis and meta-regression were used to identify sources of heterogeneity. We included 21,069 melanoma cases from 28 studies published 1979-2018: 23 case-control (11 hospital-based, 12 population-based), 1 ecological, 3 cohort and 1 randomised controlled trial (RCT). There was marked heterogeneity across study designs and among case-control studies but adjustment for confounding by sun exposure, sunburns and phenotype systematically moved estimates toward decreased melanoma risk among sunscreen users. Ever- vs. never-use of sunscreen was inversely associated with melanoma in hospital-based case-control studies (adjusted odds ratio (OR) = 0.57, 95%confidence interval (CI) 0.37-0.87, pheterogeneity < 0.001), the ecological study (rate ratio = 0.48, 95%CI 0.35-0.66), and the RCT (hazard ratio (HR) = 0.49, 95%CI 0.24-1.01). It was not associated in population-based case-control studies (OR = 1.17, 95%CI 0.90-1.51, pheterogeneity < 0.001) and was positively associated in the cohort studies (HR = 1.27, 95%CI 1.07-1.51, pheterogeneity = 0.236). The association differed by latitude (pinteraction = 0.042), region (pinteraction = 0.008), adjustment for naevi/freckling (pinteraction = 0.035), and proportion of never-sunscreen-users (pinteraction = 0·012). Evidence from observational studies on sunscreen use and melanoma risk was weak and heterogeneous, consistent with the challenges of controlling for innate confounding by indication. The only RCT showed a protective effect of sunscreen.

Regular Sunscreen Use and Risk of Mortality: Long-Term Follow-up of a Skin Cancer Prevention Trial

INTRODUCTION

Sunscreen is widely used to protect the skin from harmful effects of sun exposure. However, there are concerns that sunscreens may negatively affect overall health. Evidence of the general safety of long-term regular sunscreen use is therefore needed.

METHODS

The effect of long-term sunscreen use on mortality was assessed over a 21-year period (1993-2014) among 1,621 Australian adults who had participated in a randomized skin cancer prevention trial of regular versus discretionary sunscreen use (1992-1996). In 2018, an intention-to-treat analysis was conducted using Cox proportional hazards regression to compare death rates in people who were randomized to apply sunscreen daily for 4.5years, versus randomized to use sunscreen at their usual, discretionary level. All-cause mortality and deaths resulting from cardiovascular disease, cancer, and other causes were considered.

RESULTS

In total, 160 deaths occurred in the daily sunscreen group compared with 170 deaths in the discretionary sunscreen group (hazard ratio=0.94, 95% CI=0.76, 1.17); 59vs 76 cardiovascular disease deaths (hazard ratio=0.77, 95% CI=0.55, 1.08), 63vs 58 cancer deaths (hazard ratio=1.09, 95% CI=0.76, 1.57), and 45vs 44 deaths resulting from other causes (hazard ratio=1.02, 95% CI=0.67, 1.54) occurred respectively.

CONCLUSIONS

Regular use of a sun protection factor 16 sunscreen on head, neck, arms, and hands for 4.5years did not increase mortality.

When to apply sunscreen: a consensus statement for Australia and New Zealand

INTRODUCTION

Cancers of the skin are the most common cancers in humans, with Australia and New Zealand having the world's highest incidence. Primary prevention campaigns advise people to apply sunscreen to exposed body sites when outdoors. However, despite growing evidence that cumulative sub-erythemal exposures cause mutational damage, and trial data demonstrating benefit from daily sunscreen use, current policies do not consider the hazards of incidental (everyday) sun exposure. Thus, a Sunscreen Summit was convened to review the evidence and update the policies for people living in Australia and New Zealand.

RESULTS

After reviewing the benefits and risks of sunscreen application, the policy group concluded that people living in Australia and New Zealand should be advised to apply sunscreen to the face/head/neck and all parts of the body not covered by clothing on all days when the ultraviolet index is forecast to reach three or greater, irrespective of their anticipated activities. For planned outdoors activities, sunscreen should be used alongside other sun protection measures.

CONCLUSIONS

People living in Australia and New Zealand are now advised to apply sunscreen every day when the UV index is predicted to reach 3 or above. Implications for public health: Increased use of sunscreen as part of the daily routine to reduce incidental sun exposure will lead to decreased incidence of skin cancer in the future.