Mackenzie R. Wehner

Indoor tanning and non-melanoma skin cancer: systematic review and meta-analysis

Objective To synthesise the literature on indoor tanning and non-melanoma skin cancer. Design Systematic review and meta-analysis. Data sources PubMed (1966 to present), Embase (1974 to present), and Web of Science (1898 to present). Study selection All articles that reported an original effect statistic for indoor tanning and non-melanoma skin cancer were included. Articles that presented no data, such as review articles and editorials, were excluded, as were articles in languages other than English. Data extraction Two investigators independently extracted data. Random effects meta-analysis was used to summarise the relative risk of ever use versus never use of indoor tanning. Dose-response effects and exposure to indoor tanning during early life were also examined. The population attributable risk fraction for the United States population was calculated. Results 12 studies with 9328 cases of non-melanoma skin cancer were included. Among people who reported ever using indoor tanning compared with those who never used indoor tanning, the summary relative risk for squamous cell carcinoma was 1.67 (95% confidence interval 1.29 to 2.17) and that for basal cell carcinoma was 1.29 (1.08 to 1.53). No significant heterogeneity existed between studies. The population attributable risk fraction for the United States was estimated to be 8.2% for squamous cell carcinoma and 3.7% for basal cell carcinoma. This corresponds to more than 170 000 cases of non-melanoma skin cancer each year attributable to indoor tanning. On the basis of data from three studies, use of indoor tanning before age 25 was more strongly associated with both squamous cell carcinoma (relative risk 2.02, 0.70 to 5.86) and basal cell carcinoma (1.40, 1.29 to 1.52). Conclusions Indoor tanning is associated with a significantly increased risk of both basal and squamous cell skin cancer. The risk is higher with use in early life (<25 years). This modifiable risk factor may account for hundreds of thousands of cases of non-melanoma skin cancer each year in the United States alone and many more worldwide. These findings contribute to the growing body of evidence on the harms of indoor tanning and support public health campaigns and regulation to reduce exposure to this carcinogen.

International prevalence of indoor tanning: a systematic review and meta-analysis.

IMPORTANCE Indoor tanning is a known carcinogen, but the scope of exposure to this hazard is not known. OBJECTIVE To summarize the international prevalence of exposure to indoor tanning. DATA SOURCES Studies were identified through systematic searches of PubMed (1966 to present), Scopus (1823 to present), and Web of Science (1898 to present) databases, last performed on March 16, 2013. We also hand searched reference lists to identify records missed by database searches and publicly available data not yet published in the scientific literature. STUDY SELECTION Records reporting a prevalence of indoor tanning were eligible for inclusion. We excluded case-control studies, reports with insufficient study information, and reports of groups recruited using factors related to indoor tanning. Two independent investigators performed searches and study selection. Our search yielded 1976 unique records. After exclusions, 161 records were assessed for eligibility in full text, and 88 were included. DATA EXTRACTION AND SYNTHESIS Two independent investigators extracted data on characteristics of study participants, inclusion/exclusion criteria, data collection format, outcomes, and statistical methods. Random-effects meta-analyses were used to summarize the prevalence of indoor tanning in different age categories. We calculated the population proportional attributable risk of indoor tanning in the United States, Europe, and Australia for nonmelanoma skin cancer (NMSC) and melanoma. MAIN OUTCOMES AND MEASURES Ever and past-year exposure to indoor tanning. RESULTS The summary prevalence of ever exposure was 35.7% (95% CI, 27.5%-44.0%) for adults, 55.0% (33.0%-77.1%) for university students, and 19.3% (14.7%-24.0%) for adolescents. The summary prevalence of past-year exposure was 14.0% (95% CI, 11.5%-16.5%) for adults, 43.1% (21.7%-64.5%) for university students, and 18.3% (12.6%-24.0%) for adolescents. These results included data from 406 696 participants. The population proportional attributable risk were 3.0% to 21.8% for NMSC and 2.6% to 9.4% for melanoma, corresponding to more than 450 000 NMSC cases and more than 10 000 melanoma cases each year attributable to indoor tanning in the United States, Europe, and Australia. CONCLUSIONS AND RELEVANCE Exposure to indoor tanning is common in Western countries, especially among young persons. Given the large number of skin cancer cases attributable to indoor tanning, these findings highlight a major public health issue.

The Risk of Melanoma in Airline Pilots and Cabin Crew: A Meta-analysis

IMPORTANCE Airline pilots and cabin crew are occupationally exposed to higher levels of cosmic and UV radiation than the general population, but their risk of developing melanoma is not yet established. OBJECTIVE To assess the risk of melanoma in pilots and airline crew. DATA SOURCES PubMed (1966 to October 30, 2013), Web of Science (1898 to January 27, 2014), and Scopus (1823 to January 27, 2014). STUDY SELECTION All studies were included that reported a standardized incidence ratio (SIR), standardized mortality ratio (SMR), or data on expected and observed cases of melanoma or death caused by melanoma that could be used to calculate an SIR or SMR in any flight-based occupation. DATA EXTRACTION AND SYNTHESIS Primary random-effect meta-analyses were used to summarize SIR and SMR for melanoma in any flight-based occupation. Heterogeneity was assessed using the χ2 test and I2 statistic. To assess the potential bias of small studies, we used funnel plots, the Begg rank correlation test, and the Egger weighted linear regression test. MAIN OUTCOMES AND MEASURES Summary SIR and SMR of melanoma in pilots and cabin crew. RESULTS Of the 3527 citations retrieved, 19 studies were included, with more than 266 431 participants. The overall summary SIR of participants in any flight-based occupation was 2.21 (95% CI, 1.76-2.77; P < .001; 14 records). The summary SIR for pilots was 2.22 (95% CI, 1.67-2.93; P = .001; 12 records). The summary SIR for cabin crew was 2.09 (95% CI, 1.67-2.62; P = .45; 2 records). The overall summary SMR of participants in any flight-based occupation was 1.42 (95% CI, 0.89-2.26; P = .002; 6 records). The summary SMR for pilots was 1.83 (95% CI, 1.27-2.63, P = .33; 4 records). The summary SMR for cabin crew was 0.90 (95% CI, 0.80-1.01; P = .97; 2 records). CONCLUSIONS AND RELEVANCE Pilots and cabin crew have approximately twice the incidence of melanoma compared with the general population. Further research on mechanisms and optimal occupational protection is needed.

Twitter: an opportunity for public health campaigns

www.thelancet.com Vol 384 July 12, 2014 131 F i n a l l y, L a b r o p o u l o s a n d colleagues seem to be dismayed that the SOX trial does not confi rm the assumed benefit of elastic compression stockings suggested by smaller trials. There are many examples of large, properly designed multicenter trials refuting results of earlier smaller trials or cohort studies. The SOX trial is the largest randomised trial so far of elastic compression stockings, overcomes the potential for bias inherent in any open trial by using placebo and double blinding, uses outcome measures used in other clinical trials of post-thrombotic syndrome, and is generalisable because of the large number of centres involved. Further, the estimated compliance rates are consistent with our clinical experience. Many patients find elastic compression stockings intolerable for aesthetic reasons, because they have the potential to cause discomfort, and can be difficult to put on. Although some might find the negative results of the SOX trial disappointing, patients might be relieved to fi nd that they do not routinely need to wear elastic compression stockings for 2 years after deep-vein thrombosis.

Timing of Subsequent New Tumors in Patients Who Present With Basal Cell Carcinoma or Cutaneous Squamous Cell Carcinoma

IMPORTANCE Patients with basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (SCC) (often termed nonmelanoma skin cancer or keratinocyte carcinoma [KC]) often develop new KCs, but information is limited on the frequency and timing of these subsequent tumors. This information is crucial to guide follow-up care. OBJECTIVE To determine the timing of subsequent new KCs in patients who present with KC. DESIGN, SETTING, AND PARTICIPANTS We enrolled a consecutive cohort of 1426 patients diagnosed as having biopsy-proven KC from January 1, 1999, through December 31, 2000, in a university dermatology practice and its affiliated Department of Veterans Affairs dermatology service. After exclusion of patients with basal cell nevus syndrome and immunocompromise, 1284 patients (90.0%) were followed up prospectively for a mean of 5.7 (range, 0-12.3) years. MAIN OUTCOMES AND MEASURES We assessed the risks for subsequent KCs over time using single-failure and multiple-failure models. We separately assessed outcomes after first lifetime KCs and after nonfirst lifetime KCs. We also performed secondary analyses of the risk for a subsequent BCC after a prior BCC diagnosis and the risk for a subsequent SCC after a prior SCC diagnosis. RESULTS The risk for a subsequent KC was substantially lower after the first lifetime KC diagnosis: 14.5% (95% CI, 11.9%-17.7%) at 1 year, 31.1% (95% CI, 27.3%-35.3%) at 3 years, and 40.7% (95% CI, 36.5%-45.2%) at 5 years, than after a nonfirst KC: 43.9% (95% CI, 42.0%-45.9%) at 1 year, 71.1% (95% CI, 69.1%-73.0%) at 3 years, and 82.0% (95% CI, 80.2%-83.7%) at 5 years. Secondary analyses of the risks for a subsequent BCC after a prior BCC diagnosis and of a subsequent SCC after a prior SCC diagnosis yielded results consistent with the analyses for the pooled KC sample. CONCLUSIONS AND RELEVANCE Although all patients with KC are assumed to be at high risk for subsequent tumors, a subset may not develop another KC after their first tumor. Whether these findings are related to biological or behavioral differences or to differences in health care services should be investigated further to inform and improve care. Ongoing routine screening for subsequent KC may not be indicated for all patients with KC. Skin cancer screening can be improved with a better understanding of the course and frequency of subsequent KC diagnoses.

Contribution of common non-synonymous variants in PCSK1 to body-mass index variation and risk of obesity: a systematic review and meta-analysis with evidence from up to 331,175 individuals

Polymorphisms rs6232 and rs6234/rs6235 in PCSK1 have been associated with extreme obesity [e.g. body mass index (BMI) ≥ 40 kg/m(2)], but their contribution to common obesity (BMI ≥ 30 kg/m(2)) and BMI variation in a multi-ethnic context is unclear. To fill this gap, we collected phenotypic and genetic data in up to 331 175 individuals from diverse ethnic groups. This process involved a systematic review of the literature in PubMed, Web of Science, Embase and the NIH GWAS catalog complemented by data extraction from pre-existing GWAS or custom-arrays in consortia and single studies. We employed recently developed global meta-analytic random-effects methods to calculate summary odds ratios (OR) and 95% confidence intervals (CIs) or beta estimates and standard errors (SE) for the obesity status and BMI analyses, respectively. Significant associations were found with binary obesity status for rs6232 (OR = 1.15, 95% CI 1.06-1.24, P = 6.08 × 10(-6)) and rs6234/rs6235 (OR = 1.07, 95% CI 1.04-1.10, P = 3.00 × 10(-7)). Similarly, significant associations were found with continuous BMI for rs6232 (β = 0.03, 95% CI 0.00-0.07; P = 0.047) and rs6234/rs6235 (β = 0.02, 95% CI 0.00-0.03; P = 5.57 × 10(-4)). Ethnicity, age and study ascertainment significantly modulated the association of PCSK1 polymorphisms with obesity. In summary, we demonstrate evidence that common gene variation in PCSK1 contributes to BMI variation and susceptibility to common obesity in the largest known meta-analysis published to date in genetic epidemiology.

Teens, Tweets, and Tanning Beds: Rethinking the Use of Social Media for Skin Cancer Prevention

The incidence of skin cancer is rising in the U.S., and melanoma, the deadliest form, is increasing disproportionately among young white women. Indoor tanning is a modifiable risk factor for all skin cancers and continues to be used at the highest rates in young white women. Adolescents and young adults report personal appearance–based reasons for using indoor tanning. Previous research has explored the influences on tanning bed use, including individual factors as well as relationships with peers, family, schools, media influences, legislation, and societal beauty norms. Adolescents and young adults also have high rates of social media usage, and research is emerging on how best to utilize these platforms for prevention. Social media has the potential to be a cost-effective way to reach large numbers of young people and target messages at characteristics of specific audiences. Recent prevention efforts have shown that comprehensive prevention campaigns that include technology and social media are promising in reducing rates of indoor tanning among young adults. This review examines the literature on psychosocial influences on indoor tanning among adolescents and young adults, and highlights ways in which technology and social media can be used for prevention efforts.

Plenty of moustaches but not enough women: cross sectional study of medical leaders

Objectives To draw attention to sex related disparities in academic medical leadership by investigating the representation of female leaders compared with leaders with moustaches. Design Cross sectional analysis. Setting Academic medical departments in the United States. Participants Clinical department leaders (n=1018) at the top 50 US medical schools funded by the National Institutes of Health (NIH). Main outcome measures The proportions of female leaders and moustachioed leaders across institutions and specialties (n=20). Additionally, the moustache index: the proportion of women compared with the proportion of moustaches, analyzed with multinomial logistic regression models. Results Women accounted for 13% (137/1018) of department leaders at the top 50 NIH funded medical schools in the US. Moustachioed leaders accounted for 19% (190/1018). The proportion of female department leaders ranged from 0% (0/20) to 26% (5/19) across institutions and 0% (0/53) to 36% (19/53) across specialties. Only seven institutions and five specialties had more than 20% of female department leaders. The overall moustache index of all academic medical departments studied was 0.72 (95% confidence interval 0.58 to 0.90; P=0.004). Only six of 20 specialties had more women than moustaches (moustache index >1). Conclusions Moustachioed individuals significantly outnumber women as leaders of medical departments in the US. We believe that every department and institution should strive for a moustache index ≥1. Known, effective, and evidence based policies to increase the number of women in leadership positions should be prioritized.

Tumor necrosis factor-α inhibitor-induced psoriasis: Systematic review of clinical features, histopathological findings, and management experience

Background: Tumor necrosis factor‐&agr; (TNF‐&agr;) inhibitors have been reported to induce new‐onset psoriasis. Objective: To better define the demographic, clinical features, and treatment approach of TNF‐&agr; inhibitor‐induced psoriasis. Methods: Systematic review of published cases of TNF‐&agr; inhibitor‐induced psoriasis. Results: We identified 88 articles with 216 cases of new‐onset TNF‐&agr; inhibitor‐induced psoriasis. The mean age at psoriasis onset was 38.5 years. The most common underlying diseases were Crohn disease (40.7%) and rheumatoid arthritis (37.0%). Patients underwent TNF‐&agr; therapy for an average of 14.0 months before psoriasis onset with 69.9% of patients experiencing onset within the first year. The majority of patients received skin‐directed therapy, though patients who discontinued TNF therapy had the greatest resolution of symptoms (47.7%) compared with those who switched to a different TNF agent (36.7%) or continued therapy (32.9%). Limitations: Retrospective review that relies on case reports and series. Conclusion: While TNF‐&agr; inhibitor cessation may result in resolution of induced psoriasis, lesions may persist. Decisions regarding treatment should be weighed against the treatability of TNF‐&agr; inhibitor‐induced psoriasis, the severity of the background rheumatologic or gastrointestinal disease, and possible loss of efficacy with cessation followed by retreatment. Skin‐directed therapy is a reasonable initial strategy except in severe cases.

A Novel Mouse Model for Frostbite Injury

BACKGROUND Frostbite injury occurs when exposure to cold results in frozen tissue. To screen drugs and other field therapies that might improve the outcome for a frostbite victim, it would be helpful to have a reliable and cost-effective preclinical in vivo model. OBJECTIVE We sought to create a novel mouse skin model of induced frostbite injury. This model would allow quantification of the surface area of involved skin, histology of the wound, rate of wound healing, and skin loss in a standardized fashion after the frostbite injury. METHODS Thirty-six mice were studied. Standardized 2.9-cm diameter circles were tattooed on the mouse dorsum. Magnets frozen in dry ice (-78.5°C) were used to create a frostbite injury on skin within the circle, either as a continuous 5-minute freeze or as 3 repeated freeze (1-minute) and thaw (3-minute) cycles. Appearance, healing rate, skin surface area loss, and histology were recorded until the wounds were healed. RESULTS The amount of skin surface area loss was approximately 50% for both freeze methods. Although the time to surface skin healing was similar for both freeze methods, the initial healing rate was significantly (P = .001) slower in mice exposed to the freeze-thaw cycles compared with the continuous freeze model. Histopathology reflected inflammatory changes, cell death, and necrosis. CONCLUSIONS This novel in vivo mouse model for frostbite allows quantification of affected skin surface area, histology, healing rate, and skin loss and has the potential of being utilized to screen future treatment modalities.