Photoprotection in Adolescence - SKINmed 2005; 4(4):229-233

Cristiane Benvenuto-Andrade, MD, MS; Tania Ferreira Cestari, MD, PhD; Adriana Mota; Claudia Poziomczyk; Marcia Ramos-e-Silva, MD, PhD

From the Sector of Dermatology and the School of Medicine, Federal University of Rio Grande do Sul, Porto Alegre, Brazil; the Sector of Dermatology, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; and the School of Medicine, Catholic University of Rio Grande do Sul, Porto Alegre, Brazil

Physical changes and the establishment of personal values are characteristics of adolescence. Despite being well informed regarding sun protection and the skin cancer risks related to sun exposure, teenagers usually make little use of sunscreens and remain out in the sun for long periods. Besides the social appeal and the impression that a nice tan provides a healthy appearance, the tendency to deny long-term risks seems to influence sun exposure behaviors in this life period. Due to the strong relation between skin cancer and sun exposure in childhood and adolescence, it is important to encourage the adoption of photoprotection measures early in life. Adolescents have difficulty accepting guidance through official educational messages, and very few of them follow family recommendations. Celebrities, fashion, and the entertainment industry exert a greater influence on their choices. Thus, it is fundamental to incorporate photoprotection counseling into the medical routine, in an adolescent-driven way. This article reviews peculiarities of sun protection in adolescence and discusses the type of advice to be given to patients in this age group.

Several studies indicate that cumulative sun exposure is the most important triggering factor for nonmelanoma skin cancers in humans. 1 Additionally, solar radiation is responsible for photoaging, immunologic disturbances, and increased incidence of ocular cataract, pterygium, and macular degeneration—disorders that can occur in all skin types, even the most pigmented. 1, 2 Unfortunately, the exact relation between UV radiation (UVR) exposure and pigmentary cell cancer (melanoma [MM]), is still unknown. Epidemiologic studies indicate that excessive intermittent solar exposure in childhood and adolescence, usually recreational, is associated with a higher risk of MM. 1, 2 Although other risk factors, such as presence of precursor lesions, age, race, history of previous MM, and family history of MM are recognized as associated with MM development, the unique thing about sunburn is the fact that it is preventable.

UVR Effects on the Skin

After sun exposure, several cytokines and inflammatory mediators, such as ecosanoids, histamine, kinins, and other chemotactic factors, are synthesized and released by skin cells. These substances act on the vascular endothelium and on keratinocytes, promoting recruitment and activation of mononuclear and polymorphonuclear cells, in addition to inducing vasodilation and inflammation (solar erythema), which can be quite intense. 3 The minimum dose of UVR required to induce erythema (sunburn) depends on factors such as radiation intensity, skin type and thickness, amount of melanin in the epidermis (constitutional pigmentation), and the amount of melanin production after sun exposure (facultative pigmentation). 2

Tanning occurs as a protective reaction. Immediately after sun exposure, there is a transient skin color change induced by UV-A radiation (UVA-R) and some ranges of visible light. This transient change occurs due to the release of preformed melanin. This effect is most intense at the end of the exposure, remaining detectable for hours. 4 After 48–72 hours, late tanning occurs. This late color change follows melanin synthesis and release, with a peak in 7–10 days, persisting for weeks or months. 4

Less visible are the UV-B radiation (UVB-R) effects on keratinocytes in the basal layer of the epidermis, and the effects of UVA-R in the connective tissue. UVB-R is responsible for DNA damage and formation of DNA photoproducts, such as pyrimidine dimers. 5 Incorrect repair of this damage may cause mutations that lead to carcinogenesis. UVA-R is much more abundant in the troposphere than UVB-R. It can indirectly affect cellular DNA by oxidative damage, which is also potentially mutagenic. 5 In the dermal compartment, the long-term effects of UVA-R on collagen are responsible for some aspects of photo aging. 6

UVR also affects the immune system, 7 triggering a decrease in antigen-presenting cell function and preferential activation of suppressor T-lymphocytes, with decreases in lymphocyte activation and production of interleukins. 8 UVR also suppresses the induction of the late hypersensitivity and granuloma formation. 4

A beneficial aspect of sun exposure is the photochemical effect that leads to vitamin D3 production. Although no definitive information is available, minimal amounts of sun exposure seem to be sufficient for maintenance of normal vitamin D levels. 9–11

Psychosocial Aspects of Adolescence

Adolescence is the stage of psychologic development that occurs during puberty. 12 The psychosocial complexity of adolescence is characterized by body image redefinition, elaboration of childhood mourning, search for similar groups, establishment of personal values, culmination of the process of separation from the original familial nucleus, and the attainment of new mental abilities. 12 In this period, ego-centrism assumes a peculiar form. Adolescents believe they are special and unique, and that others, especially peers, are watching them, and interested in all their thoughts and behaviors. This is due, in part, to emerging formal operational thought, which allows adolescents to think about their own thinking and that of others. 12 This self-absorption also contributes to the development of the so-called “personal fables” that reflect adolescents’ conviction of being immortal and unreachable by accidents and diseases. It is typical of this stage to avoid thinking about the past or the distant future. 13

The Adolescent’s Solar Behavior

Studies performed in adolescent populations indicate inadequate use of sunscreens and other photoprotective measures, despite their spending long periods in the sun. 14, 15 A significant proportion of that exposure occurs in the summer, in hours of intense radiation, with boys being more susceptible to occupational exposure, and girls to recreational exposure. 16, 17

A study of 500 adolescents conducted by the American Academy of Dermatology showed that 78% of subjects were aware of the risks of sun exposure, but 66% said that a suntan gave them a healthier appearance. 18 Similar findings were described in French and Brazilian adolescents. 19, 20 In general, the use of sun-protective measures is higher among girls, but boys are less prone to use tanning beds. 18, 21–24

Besides the social appeal, the tendency to deny long-term risks influences adolescent behavior. Thus, despite being informed about the risks of UVR exposure, and having a family history of skin cancer, some groups make regular use of tanning salons. 25

In recent years, some researchers have suggested that the profusion of indoor activities such as the use of video games, computers, and the Internet, may be reducing the total UVR dose in the first and second decades of life. 10 Nowadays, in the United States, men over 40 years of age spend much more time in the sun than people from birth to 21 years of age, 10 and children receive as much UVR as adults throughout the year. 26 Adolescents have the lowest UVR exposure. 26 If this proves to be a worldwide trend, in the future we may not be able to state that 80% of an individual’s total UVR dose is received before the age of 21.

Solar Protection Campaigns for Adolescents

Disease prevention and health promotion campaigns aim at behavioral changes, but generally those changes are very complicated and slowly assimilated at any age. 27–29 Primary prevention of skin cancer usually focus on changes in information, attitudes, and habits regarding sun exposure. Some of these strategies are likely to take up to 20 years, if effective, to reduce the morbidity/mortality of cutaneous neoplasias. 27 Nonetheless, there has already been considerable progress in this area, and several successful programs are being conducted to increase solar protection awareness in ado-lescents. 18, 27, 30 In Australia, the country with the highest rate of skin cancer in the world, prevention and detection campaigns directed at teenagers have been instituted, raising early diagnoses of skin tumors. 19

In general, measures of impact on adolescents involve the media, with attractive and convincing commercials aimed at them. 31 This group is classically difficult to guide by official or familial educational messages. 32 Celebrities, fashion icons, and the entertainment industry can influence their behaviors. 31

Photoprotection Measures in Adolescence

Sunscreens

It is estimated that regular photo-protection until the age of 18 can reduce the incidence of non-MM skin cancers up to 78%. 33 Some groups deserve special attention, such as people with xeroderma pigmentosum, skin phototype I and II, blue eyes, blond or red hair, as well as those presenting with familial dysplastic nevus syndrome, large number of melanocytic nevi, and family history of MM. 34

The sun protection factor (SPF) of a sunscreen indicates its capacity to delay erythema caused by UVB-R. Sunscreen use is effective in preventing actinic keratoses and squamous-cell carcinoma. 1, 35 Although there are no conclusive studies proving the effectiveness of sunscreens in preventing the development of MM or basal-cell carcinoma in humans, indirect evidence seems to suggest such action. 1, 2, 35, 36 The increasing concern about UVA-R effects on the skin, such as photoaging, oxidative damage to DNA, production of free radicals, and the hypotheses of a relevant role in MM induction, 37 led to the development of products conferring protection for the longer UVR rays. These products are called broad-spectrum filters, and are effective both in the UVB-R and UVA-R range. 37 Additionally, it is well documented that most of the photo dermatoses and photosensitivity reactions induced by drugs are related to the UVA-R spectrum, demanding the use of broad-spectrum filters. 37

Photo protectors should be part of the daily routine throughout the year. 2, 38, 39 Patients must be advised to apply a sunscreen of a least SPF 15, ideally SPF 30, with broad spectrum, 20 minutes before sun exposure. 1, 40 Ideally, the application should occur out of the sun and the patient should be wearing no clothes. Some authors suggest that the sunscreen should be reapplied about 15 to 30 minutes after the first layer, to render uniformity. Reapplication is necessary every 2 hours, or after excessive perspiration and water immersion. 41 The ideal dose of sunscreen to reach the SPF stated on the package is 2 mg/cm2 , with special attention to areas like the ears, nape, and dorsa of the feet. 1 Investigators have found that the amount of sunscreen applied by the population usually is well under the ideal requirement, providing protection of only one third of that described on the product’s label. 42 Therefore, physician advice must include not only the ideal SPF, but also the amount of product to be applied, regularity, and reapplication during the exposure period.

Formulas containing perfumes and dyes should be avoided at any age, because they increase risks of allergic reactions. When the sunscreen is used in combination with an insect repellent containing diethyl methyl toluamide, its protection factor is reduced, requiring the use of higher SPF filters. 40

Adolescents usually show great resistance to the use of sunscreens due to factors like cost, cosmetic aspect, and the lack of patience to apply them. 20, 35 Thus, sunscreen application should be taught very early, and incorporated into the daily routine, just like toothbrush use. Another important measure would be the development of products with pleasing cosmetic properties, low cost, and easy to apply.

General Photoprotective Measures

Family and school members are very important early sources of motivation for photoprotection. When protection becomes a habit, through school rules and family habits, it is more likely to be incorporated in future attitudes. 43 Familial outdoor activities should be avoided between 10 a.m. and 2 p.m. 2 Photo protection should be maintained on cloudy days, since clouds reduce UVR intensity by only 20%–40%. 2 Furthermore, youngsters using oral or topical medications with photosensitizing potential, such as tetracyclines, sulfonamides, psoralens, promethazine, and nonsteroidal anti-inflammatory drugs, should be educated to avoid sun exposure during the entire day. 2, 44, 45

Clothes can confer sufficient protection without the previously mentioned inconveniences attributed to sunscreens. Their shield capacity depends on the type of material, structure, color, and thickness of the fabric. 1, 2 Fabrics of tight mesh offer the greatest protection against UVR. 1 Wet clothes lose a great part of their protecting potential. 2 The protecting capacity of fabrics can be enhanced by substances that increase adhesion of the fibers, such as resins, or by more recent methods, such as substances added to detergents or softeners that deposit into the fibers, absorbing and dispersing the UVR. 46, 47

Hats with large brims protect the face, ears, neck, and eyes. Caps are not ideal, but, if used with the brim facing forward, they can avoid up to 50% of eye exposure to UVR. 1, 2

Dark glasses are suitable for eye protection and very well accepted by adolescents because they improve their status and are considered fashionable. Sunglasses should block about 99% of the UVR spectrum and fit well on the face. Sunglass lenses must be wide and used close to the eyes.

Applications in Medical Practice

General practitioners, pediatricians, and dermatologists have a fundamental role in education for sun protection from childhood to adolescence. 34 A study of adolescents in southern Brazil revealed that the main information source on the effects of UVR is the media. Schools and health professionals must be motivated to integrate consideration of photoprotection into their routine activities. 20 Physicians can exercise an active role in their patients’ education, positively influencing the adolescents and their relatives’ attitude. Taking advantage of the time spent in consultation to guide them on simple and effective practices, such as skin self-exam, is an easy way to start. 20 Although adolescent patients rarely develop cutaneous neoplasias, those at increased risk for skin cancer should have annual total body examinations and should be encouraged to practice skin self-examination on a regular basis. Schools can help by adopting measures such as covered playgrounds, concentrating outdoor activities before 10 a.m. and after 4 p.m., including caps as part of the uniform, and educating about the risks of exposure to natural and artificial sources of UVR. 2

Conclusions

Behavioral changes occur slowly. But interventions addressed at increasing sun protection awareness should not be abandoned, so that in the future we can effectively reduce the burden of skin cancer in our population.

References