PATTERNS OF SUNSCREEN USE ON THE FACE AND OTHER EXPOSED SKIN AMONG US ADULTS

Holman, D. M., Berkowitz, Z., Guy, G. P. Jr., Hawkins, N. A., Saraiya, M., & Watson, M. (2015). Patterns of sunscreen use on the face and other exposed skin among US adults. Journal of the American Academy of Dermatology, 73(1), 83.e1-92.e1.

According to previous studies, only one third of adults "usually or always" apply sunscreen when outdoors during sunny hours (Buller et al., 2011). If used properly, daily sunscreen use can significantly reduce the risk of skin cancer and minimize or delay photoaging of the skin. This study used data from Porter Novelli's 2013 Summer ConsumerStyles survey to further characterize sunscreen use among U.S. adults (GfK, 2013). The ConsumerStyles are cross-sectional online surveys created to solicit the public opinions and their behavioral trends on health issues. Participants were recruited by probability-based sampling using random-digit dialing and address-based sampling methods. The survey was completed from June 28 through July 26, 2013. It was sent to 6,102 adults aged 18 years or older. Four thousand thirty-three adults completed the survey, obtaining a 66% response rate.

Overall, 18% of men and 43% of women regularly used sunscreen on the face, and only 14% of men and 30% of women regularly used sunscreen on all exposed skin. More men than women never used sunscreen at all. Among sunscreen users, over 80% chose a sunscreen with an SPF 15 or higher, and 25% chose an SPF 50 or higher. Almost 40% of regular users were unsure if their sunscreen was broad spectrum.

Compared with non-Hispanic whites, Blacks and Hispanics were less likely to use sunscreen regularly on the face or on other exposed skin. Regardless of skin type, a higher likelihood of regular application was observed among men and women with more sun-sensitive skin compared with those whose skin did not sunburn. Those with an annual household income exceeding $60,000 were more likely to apply sunscreen regularly. Evaluating for other health conscious behaviors, those who met daily exercise guidelines were significantly more likely to regularly use sunscreen than those who did not, and current smokers were less likely to regularly use sunscreen compared with nonsmokers. Those who were overweight or obese were less likely to use sunscreen than their counterparts.

REMARKS: Only 30% of women and less than 15% of men regularly use sunscreen on all exposed skin. Some adults, particularly women, use sunscreen regularly on the face but not on other exposed skin. This pattern may reflect the use of cosmetic products containing SPF. Similarly, women may focus sunscreen use on the face for antiaging effects (Abroms, Jorgensen, Southwell, Geller, & Emmons, 2003). Sun-safety messages should encourage women to protect all skin from the sun for health concerns, specifically cancer risk. Among sunscreen users, almost half were unsure if their sunscreen provided broad-spectrum protection. When a sunscreen does not provide proper coverage, users may have a false sense of protection, possibly leading to more worrisome sun exposure. Additional health education on product requirements would help alleviate this concern. Sunscreen use was positively associated with other preventative health behaviors and should be included within the routine preventative medicine counseling. The inverse association between sunscreen use and household income suggests that cost may be a barrier to sunscreen use. Creating social supports for sun safety may help mitigate individual-level barriers (Mahe, Beauchet, de Maleissye, & Saiag, 2011).

Limitations of this study include that the study relies on self-reported information, which is subject to social desirability bias. It was conducted in summer, which could falsely elevate the rate of sunscreen use, as it is typically higher in sunnier weather. As well, the study does not include data on other skin cancer risk-related behaviors, such as tanning bed use, or other sun safety behaviors, including shade seeking, all of which should be discussed and evaluated when ensuring adequate sun protection.

Key points: The associations between sunscreen use and demographic characteristics are necessary information for future intervention efforts. Sunscreen use is particularly low among certain groups such as men, darker-skinned individuals, those with less health conscious behaviors, and those with lower incomes. These groups should be specifically targeted for further education and intervention.

SUNSCREEN USE IN PATIENTS WITH CUTANEOUS LUPUS ERYTHEMATOSUS

Gutmark, E. L., Lin, D. Q., Bernstein, I., Wang, S. Q., & Chong, B. F. (2015). Sunscreen use in patients with cutaneous lupus erythematosus. The British Journal of Dermatology, 173(3), 831-834.

Cutaneous lupus erythematosus is a chronic autoimmune disorder affecting around 1% of the population. It can either involve the skin alone or have systemic involvement. Lupus erythematosus has a variety of triggers-arguably, the most important is exposure to ultraviolet radiation (UV-R), which can induce lupus flares up to several weeks after exposure. It has long been known that diligent use of sunscreens can reduce the frequency and severity of lupus flares; thus, all patients should apply sunscreen on a regular basis.

Gutmark, Lin, Bernstein, Wang, and Chong (2015) conducted a cross-sectional survey from 2012 to 2013 to determine the prevalence of sunscreen use among patients with cutaneous lupus erythematosus in Dallas, Texas. They compared participants who were daily sunscreen users versus those who did not use sunscreen at all. The overall response rate was 67.7% (100/148). Of the 100 respondents, 32 (32%) used sunscreen daily, and 40 (40%) never used sunscreen. Among those who used sunscreen, 63% reapplied when outdoors for more than 1 hour. A multivariate analysis found that being married (p = .04) and having a college degree (p = .03) were associated with daily sunscreen use. "Forgetfulness" and "greasiness" were common reasons not to use sunscreen. A belief that sunscreens were ineffective in reducing lupus flares was cited in 41% of the participants.

REMARKS: Sunscreen use is the foundation of the management of cutaneous lupus erythematosus. This cross-sectional study highlights the poor adherence to standard sunscreen recommendations with less than one third of patients with lupus using sunscreen daily. Reasons cited included simply forgetting and the cosmetic appeal of commercial sunscreens. Over 40% of the participants did not feel that sunscreen reduced lupus flares. This is despite evidence that sunscreen reduces UV damage. For example, a study of 20 patients with lupus found that application of a broad-spectrum sunscreen prevented cell damage and inflammation immediately after exposure to UV-R on histopathologic examination (Zahn et al., 2014). A double-blinded, placebo-controlled randomized controlled trial on sunscreen use included 25 patients with lupus. It found significantly (p < .001) fewer skin lesions in sunscreen-protected skin after UV-R exposure (Kuhn et al., 2011).

This study reinforces the need for patient education on sun protection practices, including sunscreen use, among patients with lupus erythematosus. Clinicians should consider more detailed and frequent counseling on the potential benefits of daily sunscreen application in reducing lupus flares. Given that "greasiness" was commonly cited as a factor in not using sunscreen, patients should be introduced to a variety of sunscreens, including newer products that have a more matte finish and may be more cosmetically appealing. Future research on sun protection should include a qualitative study with group interviews to generate a more in-depth understanding on patient perceptions and preferences.

Key points: Patients with cutaneous lupus erythematosus often do not use daily sunscreen and require counseling on its benefits in reducing lupus flares.

AZATHIOPRINE TREATMENT OF INTRACTABLE PRURITUS: A RETROSPECTIVE REVIEW

Maley, A., & Swerlick, R. A. (2015). Azathioprine treatment of intractable pruritus: A retrospective review. Journal of the American Academy of Dermatology, 73(3), 439-443.

Chronic pruritus is a debilitating and difficult-to-treat symptom in dermatology. It is central to many common diseases including atopic dermatitis, psoriasis, allergic contact dermatitis, prurigo nodularis, and urticaria (Yosipovitch and Bernhard, 2013). Previous studies have shown that pruritus is associated with decreased quality of life and can be as debilitating as chronic pain (Kini et al., 2011). Standard first-line treatments for pruritus include emollients, topical corticosteroids, phototherapy, antihistamines, gabapentin, and selective serotonin reuptake inhibitors (Yosipovitch and Bernhard et al., 2013). For treatment-resistant cases, the therapeutic options are less well established, and finding an effective option for patients can be challenging.

Maley and Swerlick (2015) conducted a retrospective chart review of 96 patients with severe chronic pruritus who were treated with azathioprine. Azathioprine is a 6-mercaptopurine analog that interferes with purine synthesis, thereby inhibiting lymphocyte activity (Tavadia et al., 2000). Patients in the study group had several dermatologic conditions including contact dermatitis, drug allergy, prurigo nodularis, lichen simplex, urticarial, and primary pruritus. All patients had pruritus that was resistant to topical corticosteroids and antihistamines; many had also failed topical calcineurin inhibitors, antibiotics, methotrexate, cyclosporine, mycophenolate mofetil, leukotriene inhibitors, phototherapy, dapsone, antiparasitics, antifungals, and gabapentin. The authors included patients who had at least 6 weeks of pruritus symptoms and unremarkable clinical and laboratory investigations. Patients whose pruritus was secondary to an underlying cause (such as end-stage renal disease or cholestasis) were excluded. They treated patients with a mean starting dose of 137.5 mg daily, with the dose adjusted for thiopurine methyltransferase levels.

Patients were asked to rate their itch on a visual analog scale from 0 to 10, with 10 being the worst itch they could imagine. After a mean duration of azathioprine treatment of 15.91 months, the investigators found a statistically significant improvement in itch. The mean itch score went from 9.25 (3-10, SD = 1.37) in the pretreatment assessment to 1.63 (0-8, SD = 1.67). Adverse events were seen in 62 (64.6%) of the patients and included transaminitis, gastrointestinal upset, azathioprine hypersensitivity syndrome, myelosuppression, infection, hair loss, and malignancy. Nine patients developed malignancy (basal cell carcinoma [4], squamous cell carcinoma [3], breast cancer [1], and squamous cell carcinoma of the tongue base [1]). Forty patients (41.6%) discontinued treatment during the study period, of which eight were able to resume the medication after a drug holiday.

REMARKS: This is an interesting retrospective review of the efficacy and tolerability of azathioprine in treating chronic pruritus. The investigators show that azathioprine is effective in significantly reducing itch in patients who have failed multiple treatments. These findings build on previous studies that have examined the role of azathioprine in treating itch associated with atopic dermatitis (Berth-Jones et al., 2002; Meggitt, Gray, & Reynolds, 2006). Limitations of the study relate primarily to its retrospective design, which led to a lack of standardization of azathioprine dosing. The patients and investigators were not blinded to the treatment, and this may have led to bias. Furthermore, patients may have used concomitant treatments including topical corticosteroids and antihistamines. Nevertheless, the authors were successful in showing a statistically significant improvement in itch after azathioprine treatment and adequately balanced their findings with mention of several adverse effects of azathioprine, perhaps, most notably, the increased risk of cancer. The study also has good generalizability and external validity, given the diverse patient selection and real-world setting.

Key points: Azathioprine is an effective, moderately priced treatment option for severe intractable pruritus. Adverse effects such as transaminitis, hypersensitivity syndrome, and malignancy should be monitored while patients are on this medication.

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