IMPORTANCE UV radiation (UVR) exposure is the primary environmental risk factor for developing cutaneous malignant melanoma (CMM). OBJECTIVE To measure changes in sun behavior from the first until the third summer after the diagnosis of CMM using matched controls as a reference. DESIGN, SETTING, AND PARTICIPANTS Three-year follow-up, observational, case-control study performed from May 7 to September 22, 2009, April 17 to September 15, 2010, and May 6 to July 31, 2011, at a university hospital in Denmark of 21 patients with CMM and 21 controls matched to patients by sex, age, occupation, and constitutive skin type participated in the study. Exposure to UVR was assessed the first and second summers (n=20) and the first and third summers (n=22) after diagnosis. Data from 40 participants were analyzed. MAIN OUTCOMES AND MEASURES Exposure to UVR was assessed by personal electronic UVR dosimeters that measured time-related UVR in standard erythema dose (SED) and corresponding sun diaries (mean, 74 days per participant each participation year). RESULTS Patients' daily UVR dose and UVR dose in connection with various behaviors increased during follow-up (quantified as an increase in daily UVR dose each year; all days: mean, 0.3 SED; 95% CI, 0.05-0.5 SED; days with body exposure: mean, 0.6 SED; 95% CI, 0.07-1.2 SED; holidays: mean, 1.2 SED; 95% CI, 0.3-2.1 SED; days abroad: 1.9 SED; 95% CI, 0.4-3.4 SED; and holidays with body exposure: mean, 2.3 SED; 95% CI, 1.1-3.4 SED). After the second year of follow-up, patients' UVR dose was higher than that of controls, who maintained a stable UVR dose. No difference was found between groups in the number of days with body exposure or the number of days using sunscreen in the second and third years of follow-up. CONCLUSIONS AND RELEVANCE Our findings suggest that patients with CMM do not maintain a cautious sun behavior in connection with an increase in UVR exposure, especially on days with body exposure, when abroad, and on holidays.
Actinic prurigo, an idiopathic familial photodermatosis, has been described in Amerindians in Manitoba, Canada, as well as in the United States, Mexico, and South America.
Our purpose was to describe the clinical features and prognosis of actinic prurigo in Amerindians in Saskatchewan, Canada.
Clinical examinations, questionnaires, phototesting, and laboratory tests were used.
We present a series of 93 Amerindian patients. The face is the most commonly involved area. A hereditary tendency, cheilitis, and pruritus are prominent features. One third of patients report some lesions, often minor, during the winter. The majority of patients phototested were sensitive to ultraviolet A light.
We find the age of onset of actinic prurigo to be the most important feature in determining the type of eruption and the prognosis for the patient. In general the younger ages of onset (up to 20 years of age) are associated with cheilitis and more acute eruptions and are more likely to improve over 5 years. Those who develop actinic prurigo as adults (21 years of age and older) tend to have a milder and more persistent dermatosis.
Comment In: J Am Acad Dermatol. 1997 Mar;36(3 Pt 1):504-59091504
The aim was to examine a possible association of amount of sunshine and risk for acute closed angle glaucoma.
This was a retrospective analysis of hospital discharge registry data, linked to meteorological data for the same period.
The study was a national survey using hospital discharge data for the whole of Finland over a 10 year period.
All subjects with the acute closed angle glaucoma diagnosis from the hospital discharge registry were collected for the years 1972 to 1982. A total of 1796 patients were found.
Meteorological data from two cities in Finland, Helsinki and Oulu, were collected for the same years from the Finnish Meteorological Institute. A peak incidence of acute closed angle glaucoma was noted whenever the number of hours without sunshine increased. A regression analysis including incidence of acute closed angle glaucoma as a dependent variable, and sex, mean temperature, mean air pressure, mean humidity, total amount of rain per month, and mean sunshine hours as independent variables, was constructed. Sex and sunshine hours best explained the variation in incidence in a covariate model. No other meteorological variate could improve the model fit.
The result confirms that the number of hours without sunshine is positively associated with the incidence of acute closed angle glaucoma, when other meteorological variables are controlled for.
The risk of non-melanoma skin cancer in northern Europeans who indulge in sunbathing or use a UVA solarium was estimated using a mathematical model of skin cancer incidence that makes allowance for childhood, occupational and recreational sun exposure. This model demonstrates that the cumulative incidence of skin cancer in indoor workers is about 2-3% by the age of 70, yet this risk can increase 5-fold if they indulge in a two-week sunbathing vacation each summer. The use of a UVA solarium is also shown to increase the risk of skin cancer. Because risk increases with the approximate square of annual solarium exposure, it is not possible to define a 'safe' level of exposure. Instead, it is shown that weekly use of a UVA solarium from age 20 until middle age (40-50) gives a relative cumulative incidence of 1.3 compared with non-users of sun beds and sun canopies. The risk begins to increase rapidly for more frequent use, particularly when solaria are used in combination with sunbathing.
In Sweden, individuals with dysplastic naevus syndrome (DNS-D2), a high risk group for malignant melanoma, are regularly screened and informed about self-examination and sun protection. During the summer of 1994, 54 out of 65 consecutive patients completed 1 month of daily self-recordings of sun-related behaviour. The diary report was compared with questionnaire responses obtained 6 months later concerning sun-related behaviour, both habitual and during the month of self-recording. The correspondence between the sun-related behaviour recorded in the diary and given in response to the questionnaire was fairly high, but 48% underestimated and 29% overestimated their actual number of sunbathing occasions in the questionnaire. Few patients indicated habitual high frequencies of sunbathing, although some of them recorded six or more occasions during 1 month in the diary. Those who recorded multiple sunburns reported the highest number of sunburns in the questionnaire. Patients who scored high on sunbed use also recorded high numbers of sunbathing occasions. Diaries should be used when detailed information about the magnitude of sun-related behaviour is essential, whereas questionnaires should be sufficient in studies aiming to differentiate between high and low frequencies of such behaviour.
To get an optimal vitamin D supplement from the sun at a minimal risk of getting cutaneous malignant melanoma (CMM), the best time of sun exposure is noon. Thus, common health recommendations given by authorities in many countries, that sun exposure should be avoided for three to five hours around noon and postponed to the afternoon, may be wrong and may even promote CMM. The reasons for this are (1) The action spectrum for CMM is likely to be centered at longer wavelengths (UVA, ultraviolet A, 320-400 nm) than that of vitamin D generation (UVB, ultraviolet B, 280-320 nm). (2) Scattering of solar radiation on clear days is caused by small scattering elements, Rayleigh dominated and increases with decreasing wavelengths. A larger fraction of UVA than of UVB comes directly and unscattered from the sun. (3) The human body can be more realistically represented by a vertical cylinder than by a horizontal, planar surface, as done in almost all calculations in the literature. With the cylinder model, high UVA fluence rates last about twice as long after noon as high UVB fluence rates do. In view of this, short, nonerythemogenic exposures around noon should be recommended rather than longer nonerythemogenic exposures in the afternoon. This would give a maximal yield of vitamin D at a minimal CMM risk.
Women with active sunlight exposure habits experience a lower mortality rate than women who avoid sun exposure; however, they are at an increased risk of skin cancer. We aimed to explore the differences in main causes of death according to sun exposure.
We assessed the differences in sun exposure as a risk factor for all-cause mortality in a competing risk scenario for 29 518 Swedish women in a prospective 20-year follow-up of the Melanoma in Southern Sweden (MISS) cohort. Women were recruited from 1990 to 1992 (aged 25-64 years at the start of the study). We obtained detailed information at baseline on sun exposure habits and potential confounders. The data were analysed using modern survival statistics.
Women with active sun exposure habits were mainly at a lower risk of cardiovascular disease (CVD) and noncancer/non-CVD death as compared to those who avoided sun exposure. As a result of their increased survival, the relative contribution of cancer death increased in these women. Nonsmokers who avoided sun exposure had a life expectancy similar to smokers in the highest sun exposure group, indicating that avoidance of sun exposure is a risk factor for death of a similar magnitude as smoking. Compared to the highest sun exposure group, life expectancy of avoiders of sun exposure was reduced by 0.6-2.1 years.
The longer life expectancy amongst women with active sun exposure habits was related to a decrease in CVD and noncancer/non-CVD mortality, causing the relative contribution of death due to cancer to increase.
Sunlight exposure and fair skin are major determinants of human vitamin D production, but they are also risk factors for cutaneous malignant melanoma (MM). There is epidemiological evidence that all-cause mortality is related to low vitamin D levels.
We assessed the avoidance of sun exposure as a risk factor for all-cause mortality for 29 518 Swedish women in a prospective 20-year follow-up of the Melanoma in Southern Sweden (MISS) cohort. Women were recruited from 1990 to 1992 and were aged 25 to 64 years at the start of the study. We obtained detailed information at baseline on their sun exposure habits and potential confounders. Multivariable flexible parametric survival analysis was applied to the data.
There were 2545 deaths amongst the 29 518 women who responded to the initial questionnaire. We found that all-cause mortality was inversely related to sun exposure habits. The mortality rate amongst avoiders of sun exposure was approximately twofold higher compared with the highest sun exposure group, resulting in excess mortality with a population attributable risk of 3%.
The results of this study provide observational evidence that avoiding sun exposure is a risk factor for all-cause mortality. Following sun exposure advice that is very restrictive in countries with low solar intensity might in fact be harmful to women's health.