An Exploration of the Use and Impact of Preventive Measures on Skin Cancer

Carvedilol Prevents UV-Induced Immunosuppression and Skin Carcinogenesis through a Mechanism Independent of β-Blockade

Exposure to UVR suppresses the immune system, which plays a primary role in skin cancer etiology. The β-blocker carvedilol prevents UV-induced skin cancer, but the mechanism is unknown. This study examined the effects of carvedilol and its enantiomers on UV-induced immunosuppression using contact hypersensitivity (CHS) response in SKH-1 mice. A single-dose UVR (224 mJ/cm2) strongly suppressed CHS, which was attenuated by intraperitoneal injection of carvedilol before UV exposure. Adoptive transfer of lymphocytes isolated from UV-irradiated mice to naïve mice without UV exposure triggered CHS suppression, which was not observed for lymphocytes isolated from carvedilol-treated mice. Topically applied carvedilol also prevented UV-induced CHS suppression. Both the β-blocking S-carvedilol and non-β-blocking R-carvedilol attenuated UV-induced CHS suppression. To evaluate the role of β2-adrenergic receptor, a knockout mouse model of β2-adrenergic receptor on the SKH-1 background was used. UV suppressed CHS in β2-adrenergic receptor-knockout mice, and carvedilol attenuated UV-induced CHS suppression in both genotypes. Furthermore, wild-type and knockout mice exposed to chronic UVR developed skin tumors with similar incidence, multiplicity, and tumor burden, whereas carvedilol inhibited skin tumor development in both genotypes. These data suggest that carvedilol prevents skin cancer not through β-blocking but through its activity overcoming UV-induced immunosuppression.

Examining U.S. Adults Risk Perceptions and Skin Protection Behaviors Using the 2022 HINTS Database

Background

This study aims to provide a general overview of cancer risk perceptions and reported sunburns to prevent sunburn and reduce the long-term risk of developing skin cancer.

Methods

Data were obtained from the 2022 Health Information National Trends Survey 6 and analysis was carried out with SPSS. Descriptive statistics were conducted to explore sociodemographic characteristics, cancer risk perceptions, and behaviors surrounding sunburns in our sample. Associations between number of sunburns and sociodemographic variables were reported using multinomial regression analysis.

Results

When asked how confident patients felt about their ability to take good care of their own health, most respondents felt either very confident (44.0%) or completely confident (27.3%). When asked how often they experienced a sunburn in the past 12 months, 2.1% reported experiencing more than 6 sunburns, 30.3% reported having between 1-5 sunburns, and 67.6% reported experiencing no sunburns. Using multinomial regression analysis, statistically significant associations were reported between number of sunburns and age, gender, occupation status, marital status, education, Hispanic origin, race, and income level.

Conclusion

The results of our study reinforce the need for public health interventions that effectively disseminate information on skin cancer risk across ethnic minority groups, especially in underserved communities within the U.S.

Sunscreen Coverage as Preventive Care Under the Affordable Care Act: A Low-Cost Way to Reduce the Prevalence of the Most Common Cancer

Skin cancer is the most commonly diagnosed malignancy in the United States, costing more than $8.1 billion annually in treatment-related expenses, yet with ultraviolet exposure considered the most significant risk factor for skin cancer development, cutaneous malignancy is also highly preventable. The Affordable Care Act (ACA) is committed to covering demonstrably effective preventive health care measures without patient cost sharing. To prevent skin cancer, the American Academy of Dermatology recommends applying sunscreen, donning sun-protective clothing, seeking shade, and avoiding midday sun. Additionally, The US Preventive Services Task Force recommends behavioral counseling for skin cancer prevention, including application of broad-spectrum sunscreen, from ages six months to 24 years of age. Despite these evidence-based recommendations and widespread precedent for ACA coverage of certain over-the-counter medications, dermatologic products such as sunscreen are notably excluded. Herein, we address an under-recognized insurance coverage gap for patients by outlining the evidence that sunscreen, as a primary prevention, dually reduces skin cancer incidence and healthcare costs, highlighting the critical need to address barriers to sunscreen utilization. As such, we advocate for amendment of current ACA coverage to include the cost of sunscreen as an evidence-based strategy to decrease the incidence of UV-induced cutaneous disease and associated treatment expenses.

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.

Sun Exposure Awareness and Sunscreen Use Among College Students in Saudi Arabia: A Cross-Sectional Analysis

BACKGROUND

Excessive sun exposure is a significant risk factor for various skin conditions, including sunburn, premature aging, and skin cancer. This study aimed to assess the awareness, attitudes, and practices regarding sun exposure and sunscreen use among college students in Saudi Arabia.

METHODOLOGY

A cross-sectional study was conducted with 388 college students from various disciplines. Data were collected using a structured questionnaire covering demographic information, awareness, and practices related to sun exposure and sunscreen use. Descriptive statistics and chi-square tests were employed to analyze the data.

RESULTS

This study comprised 209 (53.9%) females and 179 (46.1%) males, with the majority aged between 18 and 23 years. Formal education on sun exposure dangers was lacking in 43.0% (167) of participants. The most recognized consequences of excessive sun exposure were sunburn (313, 80.6%) and skin cancer (289, 74.4%). Factors influencing sunscreen use included weather conditions and healthcare provider recommendations. Males were significantly less likely to use sunscreen compared to females. First-year students and participants without formal education on sun exposure were less likely to use sunscreen regularly.

CONCLUSION

Despite awareness of the risks associated with excessive sun exposure, sunscreen use among college students in Saudi Arabia is inconsistent and influenced by various factors, including gender and education level.

Skin cancer in patients who are co-infected with HIV/ HBV or HIV/HCV: a systematic review

Skin cancer, the most common cancer in the United States, has been well-described in the literature to be associated with environmental factors including ultraviolet (UV) radiation. However, the effect of chronic viral infections on risk of skin cancer development, particularly in individuals co-infected with Human Immunodeficiency Virus (HIV) and Hepatitis B or C Viruses (HBV/HCV), has yet to be elucidated. This systematic review aims to be one of the first to consolidate existing literature and examine the relationship between skin cancer and HIV/HBV and HIV/HCV co-infections. We conducted a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, searching MEDLINE, Embase, Cochrane CENTRAL, and Web of Science databases for studies published from inception to March 26, 2024. Inclusion criteria for studies included only those reporting on HBV and/or HCV in people living with HIV (PLWH). Five studies were ultimately included for analysis. The review identified multiple non-melanoma skin cancers (NMSC) and cutaneous adnexal carcinomas in HIV/HCV or HIV/HBV co-infected patients. Notably, Pilomatrical carcinomas were observed in co-infected individuals. Sarcomas including Kaposi sarcoma and low-grade fibroblastic sarcoma were also linked to HIV/HCV or HIV/HBV infections. However, the studies primarily focused on specific types of cancers without elucidating the underlying mechanisms for the association between HIV/HCV/HBV infection and sarcoma development. In summary, this review suggests a potential link between HIV/HCV and HIV/HBV co-infection and certain types of skin cancer, namely adnexal carcinomas. Further research is crucial to determine the underlying mechanisms, explore the association with different skin cancer types, and identify effective prevention and treatment strategies for co-infected individuals.

Skin Cancer and Other Dermatologic Conditions Among US Veterans

Importance

US veterans may be at an increased risk of developing various dermatologic conditions compared with nonveterans.

Objectives

To compare the prevalence and the odds of dermatologic conditions (eg, skin cancers, dermatitis/eczema/rash, psoriasis) between veterans and nonveterans.

Design, Setting, and Participants

This population-based cross-sectional study leveraged nationally representative data from the National Health and Nutrition Examination Survey (NHANES). Three questionnaires (demographics, medical conditions, and dermatology) were merged from 1999-2018 for analysis. Participants were nonveterans and veterans from NHANES data. Data were analyzed from August 2023 to April 2024.

Main Outcomes and Measures

The prevalence and odds ratios (ORs) comparing veterans and nonveterans were examined for various dermatologic conditions, including self-reported skin cancer history (any skin cancer, melanoma, nonmelanoma and unknown subtypes), dermatitis/eczema/inflamed rash, and psoriasis.

Results

In a total of 61 307 participants (54 554 nonveterans and 6753 veterans), there was a higher prevalence of any skin cancer history among US veterans compared with nonveterans (9.0% vs 2.9%; P < .001) as well as a higher prevalence of melanoma history (2.2% vs 0.6%; P < .001). Adjusted for demographic factors, veterans had higher odds of any skin cancer history (OR, 1.72; 95% CI, 1.23-2.40) and higher odds of a melanoma history (OR, 2.27; 95% CI, 1.17-4.39) compared with nonveterans. Veterans had a higher prevalence of a psoriasis diagnosis compared with nonveterans (4.5% vs 2.9%; P = .002) and a 61% higher odds of a psoriasis diagnosis (OR, 1.61; 95% CI, 1.05-2.46) compared with nonveterans.

Conclusions and Relevance

This cross-sectional study found that veterans have higher prevalence and odds of various dermatologic conditions compared with nonveterans. Efforts aimed at improving health care quality among veterans must investigate the underlying causes of worsened skin health in this population.

Examination of a Novel Intervention Strategy to Promote Sunscreen Use: A Feasibility Study

Objective

Skin cancer remains prevalent despite numerous studies reporting the benefits of sunscreen for reducing risk of skin cancer and sunburn. While the risks of not wearing sunscreen are well-documented, there are no effective interventions to promote sunscreen use across populations, and existing interventions have modest outcomes. The current study investigated a novel intervention to increase sunscreen use.

Methods

Participants (n=15) first reported their baseline daily sunscreen use then completed sunscreen sampling and selection procedures that included testing sunscreen samples, choosing preferred sunscreens to take home and sample further, and ultimately selecting a preferred sunscreen to use for the remainder of the study. Participants then self-reported their daily sunscreen use for approximately two weeks (+/-5 days).

Results

All participants increased sunscreen use following intervention.

Limitations

Data were collected between January and May; individuals may increase sunscreen use as temperatures increase (and time outdoors increases). Additionally, the current study relied on self-report of sunscreen use primarily.

Conclusion

Our findings suggest that sampling and election procedures may be an effective strategy to promote sunscreen use. The findings of this study may inform future research examining sunscreen intervention strategies.

The Relationship between Vitamin D Levels and Blood Glucose and Cholesterol Levels

BACKGROUND

Vitamin D deficiency has reached epidemic proportions globally. Observational data link low vitamin D status to diabetes, dyslipidemia, and metabolic syndrome, but interventional trials on the effects of supplementation are limited.

OBJECTIVE

We investigated associations between serum 25-hydroxyvitamin D (25(OH)D) levels and metabolic markers in Saudi adults.

METHODS

This retrospective cross-sectional study analyzed the clinical records of 476 patients from Saudi Arabia, aged 15-78 years. According to 25(OH)D levels, participants were stratified as vitamin D-sufficient (≥30 ng/mL), -insufficient (21-29 ng/mL), or -deficient (≤20 ng/mL). The outcomes were diabetic status (fasting glucose, HbA1c) and lipid panel results.

RESULTS

Higher diabetes prevalence was significantly associated with lower 25(OH)D levels (10.1% in the sufficient group, 11.6% in the insufficient group, and 18.3% in the deficient group). Similarly, worse lipid profiles were associated with more severe hypovitaminosis D, including a total cholesterol level of ≥240 mg/dL (5.3% in participants with normal vitamin D levels vs. 18.9% in those with deficient levels) and LDL ≥ 160 mg/dL (6.9% in participants with normal vitamin D levels vs. 13.2% in those with deficient levels). Vitamin D deficiency disproportionately affected women and adults > 45 years old.

CONCLUSIONS

Vitamin D deficiency is endemic in Saudi Arabia and strongly linked to worsened metabolic markers. Optimizing vitamin D status through screening and correcting the deficiency may provide a cost-effective approach to confronting the regional diabetes epidemic and reducing cardiovascular disease risk.

DDCNN-F: double decker convolutional neural network 'F' feature fusion as a medical image classification framework

Melanoma is a severe skin cancer that involves abnormal cell development. This study aims to provide a new feature fusion framework for melanoma classification that includes a novel 'F' Flag feature for early detection. This novel 'F' indicator efficiently distinguishes benign skin lesions from malignant ones known as melanoma. The article proposes an architecture that is built in a Double Decker Convolutional Neural Network called DDCNN future fusion. The network's deck one, known as a Convolutional Neural Network (CNN), finds difficult-to-classify hairy images using a confidence factor termed the intra-class variance score. These hirsute image samples are combined to form a Baseline Separated Channel (BSC). By eliminating hair and using data augmentation techniques, the BSC is ready for analysis. The network's second deck trains the pre-processed BSC and generates bottleneck features. The bottleneck features are merged with features generated from the ABCDE clinical bio indicators to promote classification accuracy. Different types of classifiers are fed to the resulting hybrid fused features with the novel 'F' Flag feature. The proposed system was trained using the ISIC 2019 and ISIC 2020 datasets to assess its performance. The empirical findings expose that the DDCNN feature fusion strategy for exposing malignant melanoma achieved a specificity of 98.4%, accuracy of 93.75%, precision of 98.56%, and Area Under Curve (AUC) value of 0.98. This study proposes a novel approach that can accurately identify and diagnose fatal skin cancer and outperform other state-of-the-art techniques, which is attributed to the DDCNN 'F' Feature fusion framework. Also, this research ascertained improvements in several classifiers when utilising the 'F' indicator, resulting in the highest specificity of + 7.34%.

Photoprotective measures among adolescents stratified by region: An analysis utilizing the National College Health Assessment

BACKGROUND/PURPOSE

Exposure to sunlight has been shown to cause pigmentary alterations, photoaging and photocarcinogenesis. Understanding photoprotective patterns in adolescent populations is beneficial to public health initiatives. We utilized data provided by the American College Health Association's National College Health Assessment to evaluate photoprotective behaviors among adolescent populations.

METHODS

Behavioral questions related to photoprotection were analyzed from the American College Health Association (ACHA) National College Health Assessment (NCHA) (Version III).

RESULTS

When comparing races, Black/African American respondents had the lowest association of practicing photoprotective behaviors in comparison to white respondents (p < .05). When comparing US geographic regions, the south had the lowest association of photoprotective measures (p < .05).

LIMITATIONS

The response rate of each institution varied, although there was still a large quantity of respondents. Finally, we cannot discern the specific reasoning for adolescent populations not using sunscreen.

CONCLUSION

These data identify demographics where efforts to enhance education on photoprotective behaviors, specifically among skin of color and southern population, to support public health initiatives.

Are in-market control systems for sunscreens adequate for consumer protection? A review of the legal framework regulating sun protection factor labels in Europe

Public health authorities and regulations in Europe protect the population against the damaging effects of excessive solar ultraviolet radiation through, among other means, monitoring marketed sunscreens and enforcing compliance with sun protection factor labelling requirements. In-market control processes are fundamental and complementary to other public health initiatives in a context of suboptimal sunscreen use in real-world settings. However, the laboratory testing method used for determining the sun protection factor of sunscreens is known to produce variability of results. The combination of an inherently variable testing method with the necessary rigidity of regulations generates volatility in the decision-making process followed by regulators during official in-market controls and exposes sunscreens to be susceptible to accidental mislabelling challenges. This leads to a paradoxical situation that may leave most sunscreens incorrectly labelled in the market and to a potential dilemma for authorities. The issue may get further amplified when non-official sources echo and broadcast uncontrolled messages about sunscreens to the public. Amending current regulation with a tolerance level to compare results that accommodates the variability of results from sun protection factor tests would ease decision-making, bring robustness to an uncertain legal landscape, make more efficient the efforts to convey consistent public health messages about the benefits of sunscreen use and better protect users. There are precedents of using tolerance levels for regulatory decision-making in other fields, and a review of the applicable legal landscape in Europe reveals that implementing it for sunscreens would only require one change to current cosmetics law.

Factors associated with older adults' knowledge, attitude and practice on skin cancer prevention

OBJECTIVES

to identify factors associated with older adults' knowledge, attitude and practice regarding skin cancer prevention.

METHODS

this is a cross-sectional study, carried out with 120 older adults from a Basic Health Unit in Quixadá, Ceará, from September to November 2018.

RESULTS

individuals aged 60 to 69 years and working were statistically associated with adequate knowledge (p=0.038). Having light skin, eyes and hair was associated with adequate attitude (p=0.030). Having skin problems, such as bleeding wounds, was associated with adequate practice (p=0.016). With regard to inappropriate behavior for skin cancer prevention, there was a statistically significant association between working or having worked under direct exposure to the sun, inadequate knowledge (p=0.036), inadequate attitude (p=0.010) and having incomplete primary education and inadequate practice (p<0.001).

CONCLUSIONS

sociodemographic and clinical factors influence older adults' knowledge, attitude and practice regarding skin cancer prevention.

Outcomes and Follow-Up Data From Two Skin Cancer Screening Events

This study investigated the outcomes and follow-up behaviors of participants from two free skin cancer screening events in the United States. This survey, with 296 participants and a 31% response rate, gathered information on participant demographics, personal history of skin cancer, knowledge of skin screening practices, and follow-up behaviors. There was a high follow-up rate of 92.3% among individuals recommended for further dermatological consultation, but a low (22%) concordance rate between the preliminary diagnoses from the screening and patient-recalled diagnoses. Additionally, about one-sixth of participants identified limited access to care as a motivation for participating in the screening. The study emphasizes the need to improve awareness about the limitations of free screenings, enhance participant education, and ensure equitable access to skin cancer screening. Future research should focus on factors influencing follow-up behaviors and the development of targeted interventions to increase awareness and access to skin cancer screening.

Current practice and beliefs of parents toward sunscreen use for their children: A cross-sectional study

Parents are generally influencing the sun protection behaviors of their children, including sunscreen use. In Saudi Arabia, sunscreen use was estimated in adults but not children. The objective was to estimate the prevalence and predictors of sunscreen use among parents and their children. An observational cross-sectional study was conducted in April 2022. Parents who were visiting outpatient clinics at a university hospital in Al-Kharj city, Saudi Arabia, were invited to complete an online questionnaire. A total of 266 participants were included in the final analysis. The mean age of parents was 39.0 ± 8.9 years, and the mean age of children was 8.2 ± 3.2 years. The prevalence of sunscreen use was 38.7% in parents and 24.1% in their children. Females had higher sunscreen use than males in both parents (49.7% versus 7.2%, p < 0.001) and in children (31.9% versus 18.3%, p = 0.011). The most frequent sunburn protection measures practiced by children were wearing long-sleeved clothes (77.0%), sitting in the shade (70.6%), and wearing hats (39.2%). In multivariable analysis, predictors of sunscreen use in parents included female sex, history of sunburn, and sunscreen use by children. Independent predictors of sunscreen use in children included a history of sunburn, wearing hats, and practicing other sunburn protection measures on risky occasions, and sunscreen use in parents. Sunscreen use in parents and children in Saudi Arabia is still inadequate or limited. This calls for community/school intervention programs using educational activities and multimedia promotion. Further studies are needed.

Photoaging and theory-based intervention to improve sun protection behaviors in students in Zahedan: study protocol for a randomized controlled trial

BACKGROUND

Excessive exposure to solar ultraviolet (UV) radiation can cause skin cancer. Implementing new technologies and computational algorithms can potentially change the outlook for cancer prevention and facilitate early detection of melanoma, thereby reducing mortality. Mobile technology as a potential provider of health services in delivering health information and conducting interventions, especially in skin fields, where a significant part of diagnosis is based on visual examination, can be important. Evidence showed that constructs of protection motivation theory (PMT) were good predictors of practicing sun protection behaviors in students. This study will investigate whether mobile applications improve safe and healthy behaviors and affect students' reduced UV exposure.

METHOD/DESIGN

This randomized controlled trial will be conducted on 320 students on 06/04/2022 in Zahedan. We created mobile applications (Sunshine and Skin Health and WhatsApp apps). Sunshine and Skin Health app allows users to see their changed faces in three stages of adolescence, middle age, and old age based on sun protection behavior. The WhatsApp app has 27 health messages based on PMT theory, eight educational files, and a skin cancer clip that will be sent through WhatsApp during a week. Randomization will be performed using a 1:1 (control: intervention) ratio. The primary endpoint is the group difference in sun-protective behaviors and PMT constructs immediately after the intervention. The secondary endpoint is the group difference in sun-protective behaviors and PMT constructs at a 3-month follow-up. The data will be analyzed in SPSS.22, and the significance level will be considered at 0.05.

DISCUSSION

The present study examines the effectiveness of mobile applications in improving sun-protective behaviors. If this intervention enhances sun protection behaviors, it can prevent students' skin damage.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials IRCT20200924048825N1. Prospectively registered on 8 February 2021.

Exploring Mycosporine-like Amino Acid UV-Absorbing Natural Products for a New Generation of Environmentally Friendly Sunscreens

Human skin needs additional protection from damaging ultraviolet radiation (UVR: 280-400 nm). Harmful UVR exposure leads to DNA damage and the development of skin cancer. Available sunscreens offer chemical protection from detrimental sun radiation to a certain extent. However, many synthetic sunscreens do not provide sufficient UVR protection due to the lack of photostability of their UV-absorbing active ingredients and/or the lack of ability to prevent the formation of free radicals, inevitably leading to skin damage. In addition, synthetic sunscreens may negatively affect human skin, causing irritation, accelerating skin aging and even resulting in allergic reactions. Beyond the potential negative effect on human health, some synthetic sunscreens have been shown to have a harmful impact on the environment. Consequently, identifying photostable, biodegradable, non-toxic, and renewable natural UV filters is imperative to address human health needs and provide a sustainable environmental solution. In nature, marine, freshwater, and terrestrial organisms are protected from harmful UVR through several important photoprotective mechanisms, including the synthesis of UV-absorbing compounds such as mycosporine-like amino acids (MAAs). Beyond MAAs, several other promising, natural UV-absorbing products could be considered for the future development of natural sunscreens. This review investigates the damaging impact of UVR on human health and the necessity of using sunscreens for UV protection, specifically UV-absorbing natural products that are more environmentally friendly than synthetic UV filters. Critical challenges and limitations related to using MAAs in sunscreen formulations are also evaluated. Furthermore, we explain how the genetic diversity of MAA biosynthetic pathways may be linked to their bioactivities and assess MAAs' potential for applications in human health.

Patch Testing With Benzophenone-3 and -4: The North American Contact Dermatitis Group Experience, 2013-2020

Background: Benzophenone (BZP)-3 and BZP-4 are ultraviolet (UV) absorbers used in sunscreens and personal care products (PCPs) and may cause allergic contact dermatitis. Objective: To characterize positive patch test reactions to BZP-3 (10% in petrolatum [pet]) and BZP-4 (2% pet) in a screening allergen series. Methods: Retrospective analysis of patients tested to BZP-3 and BZP-4 was conducted by the North American Contact Dermatitis Group from 2013 to 2020. Results: Of 19,618 patients patch tested to BZP-3 and BZP-4, 103 (0.5%) and 323 (1.6%) had positive reactions, respectively: 413 (2.1%) reacted to at least 1 BZP (BZP-positive patient). As compared with BZP-negative patients, BZP-positive patients were significantly more likely to have a history of hay fever (39.3% vs 33.4%, P = 0.0134), history of atopic dermatitis (39.8% vs 30.7%, P = 0.0001), and facial involvement (37.4% vs 32.2%, P = 0.0272). Most reactions were currently clinically relevant (BZP-3: 90.4%; BZP-4: 65.8%). Common identified sources included PCPs and sunscreens. Coreactivity between BZP-3 and BZP-4 was low: 13.5% (14/104) of BZP-3-positive patients were allergic to BZP-4 and 4.3% (14/322) of BZP-4-positive patients were allergic to BZP-3. Conclusions: Eight-year prevalence of BZP positivity was 2.1%. Reactions were frequently clinically relevant and linked to PCPs and sunscreens.