Oral contraceptive use and risk of melanoma in premenopausal women

Melanoma has been increasing in white populations. Incidence rates rise steeply in women until about age 50, suggesting oestrogen as a possible risk factor. Oestrogens can increase melanocyte count and melanin content and cause hyperpigmentation of the skin. We examined prospectively the association between oral contraceptive (OC) use and diagnoses of superficial spreading and nodular melanoma among 183 693 premenopausal white women in the Nurses’ Health Study (NHS) and the Nurses’ Health Study II (NHS II) cohorts. One hundred and forty six cases were confirmed in NHS during follow-up from 1976 to 1994, and 106 cases were confirmed in NHS II from 1989 to 1995. Skin reaction to sun exposure, sunburn history, mole counts, hair colour, family history of melanoma, parity, height and body mass index were also assessed and included in logistic regression models. A significant twofold increase in risk of melanoma (relative risk (RR) = 2.0, 95% confidence interval (CI) 1.2–3.4) was observed among current OC users compared to never users. Risk was further increased among current users with 10 or more years of use (RR = 3.4, 95% CI 1.7–7.0). Risk did not appear elevated among past OC users, even among those with longer durations of use, and risk did not decline linearly with time since last use. In conclusion, risk of premenopausal melanoma may be increased among women who are current OC users, particularly among those with longer durations of use. Further research is needed to determine whether low-dose oestrogen pills in particular are associated with an increase in risk and to describe possible interactions between OC use and sun exposure or other risk factors for melanoma. © 1999 Cancer Research Campaig

A pooled analysis of 10 case–control studies of melanoma and oral contraceptive use

Data regarding the effects of oral contraceptive use on women's risk of melanoma have been difficult to resolve. We undertook a pooled analysis of all case–control studies of melanoma in women completed as of July 1994 for which electronic data were available on oral contraceptive use along with other melanoma risk factors such as hair colour, sun sensitivity, family history of melanoma and sun exposure. Using the original data from each investigation (a total of 2391 cases and 3199 controls), we combined the study-specific odds ratios and standard errors to obtain a pooled estimate that incorporates inter-study heterogeneity. Overall, we observed no excess risk associated with oral contraceptive use for 1 year or longer compared to never use or use for less than 1 year (pooled odds ratio (pOR)=0.86; 95% CI=0.74–1.01), and there was no evidence of heterogeneity between studies. We found no relation between melanoma incidence and duration of oral contraceptive use, age began, year of use, years since first use or last use, or specifically current oral contraceptive use. In aggregate, our findings do not suggest a major role of oral contraceptive use on women's risk of melanoma

Comparing human wayfinding behavior between a real, existing building, a virtual replica, and two architectural redesigns

While virtual reality (VR) is increasingly being used for behavioral studies and pre-occupancy evaluations, the correspondence of wayfinding behavior between real and virtual environments is yet understudied. In this chapter, we report a post- and pre-occupancy evaluation that compares wayfinding behavior in a real, existing building to three virtually simulated buildings: one replication of the real building and two architectural design variations of the same building. We focus on comparing the conditions with respect to their effect on a) the distance above a shortest, optimal path, and key wayfinding decisions, as well as b) absolute angular pointing errors. Preliminary results indicate that the virtual replica represented the real building, as the result patterns were generally comparable. Yet, the redesigns did not evoke a better wayfinding performance.ISSN:0302-9743ISSN:1611-334

Occupational exposure to ultraviolet radiation: The duality dilemma

Human exposure to ultraviolet (UV) radiation is a component of everyday life and a significant hazard for outdoor workers. In addition, a large range of artificial sources also has the potential to provide extreme occupational UV exposure. Even though the human health risks of overexposure to UV are well documented, to date relatively little is known quantitatively about UV exposure. For example, the evidence indicates that workers who are exposed to particular sources (for example, welding arcs) are exposed to extreme UV exposures, despite the use of current control measures. In contrast, increasing evidence points to significant health impacts resulting from underexposure to UV, particularly with the production (or more correctly lack of production) of vitamin D in the skin. The latter poses a serious issue for the work-force, with specific risks for workers lacking adequate sun exposure-underground miners, long-haul flight crews, shift workers, and perhaps indoor workers. Using a risk-management approach, this paper provides a comprehensive review of occupational UV sources, health impact of occupational UV exposure, occupational exposure standards, and levels of exposure in various settings, and discusses the appropriate control measures. In addition, the duality aspect of health impacts from overexposure and underexposure to UV and the associated occupational health implications are specifically explored

Assessment of a new questionnaire for self-reported sun sensitivity in an occupational skin cancer screening program

<p>Abstract</p> <p>Background</p> <p>Sun sensitivity of the skin is a risk factor for the development of cutaneous melanoma and other skin cancers. Epidemiological studies on causal factors for the development of melanoma must control for sun sensitivity as a confounder. A standardized instrument for measuring sun sensitivity has not been established yet. It is assumed that many studies show a high potential of residual confounding for sun sensitivity. In the present study, a new questionnaire for the assessment of self-reported sun sensitivity is administered and examined.</p> <p>Methods</p> <p>Prior to an occupational skin cancer screening program, the 745 participating employees were asked to fill in a questionnaire for self-assessment of sun sensitivity. The questionnaire was developed by experts of the working group "Round Table Sunbeds" (RTS) to limit the health hazards of sunbed use in Germany. A sun sensitivity score (RTS-score) was calculated using 10 indicators. The internal consistency of the questionnaire and the agreement with other methods (convergent validity) were examined.</p> <p>Results</p> <p>The RTS-score was calculated for 655 study participants who were 18 to 65 years of age. The correlation of the items among each other was between 0.12 and 0.62. The items and the RTS-score correlated between 0.46 and 0.77. The internal consistency showed a reliability coefficient with 0.82 (Cronbach's alpha). The comparison with the Fitzpatrick classification, the prevailing standard, was possible in 617 cases with a rank correlation of r_s= 0.65. The categorization of the RTS-score in four risk groups showed correct classification to the four skin types of Fitzpatrick in 75% of the cases. Other methods for the assessment of sun sensitivity displayed varying agreements with the RTS-score.</p> <p>Conclusion</p> <p>The RTS questionnaire showed a sufficient internal consistency. There is a good convergent validity between the RTS-score and the Fritzpatrick classification avoiding shortcomings of the prevailing standard. The questionnaire represents a simple, reliable and valid instrument for the assessment of sun sensitivity. The questionnaire can be useful for epidemiological studies as well as for skin cancer prevention. Further development and standardization of sun sensitivity assessments is necessary to strengthen the evidence of epidemiological studies on causal factors of melanoma and other skin cancers.</p