Interaction of Area-Level Socioeconomic Status and UV Radiation on Melanoma Occurrence in California

Abstract

Background: Melanoma incidence has been correlated strongly and positively with both socioeconomic status (SES) and lower latitude and other measures of ambient UV radiation (UVR). However, because high-SES populations may be colocated in areas of high UVR, we assessed their joint influences on melanoma occurrence to better target subpopulations for melanoma education and screening.Methods: We obtained from the California Cancer Registry information regarding 23,564 incident cases of invasive cutaneous melanoma among non-Hispanic white residents between January 1, 1998, and December 31, 2002. We geocoded each case based on residence at diagnosis and linked previously tested neighborhood measures of SES and average annual UVR to calculate age-adjusted incidence rates, rate ratios, and the corresponding 95% confidence intervals. Poisson regression was used to calculate multivariately adjusted rate ratios.Results: UVR was significantly and positively associated with melanoma incidence only among persons living in the top 40% of California neighborhoods ranked by SES. People in neighborhoods of the highest SES and UVR categories had 60% higher rates of melanoma than those from neighborhoods in the lowest categories (rate ratio, 1.60; 95% confidence interval, 1.02-2.51).Conclusion: Our findings indicate that UVR and SES interact to influence melanoma occurrence and suggest that socioeconomic gradients in melanoma incidence are not explained entirely by UVR.Impact: Cancer prevention and early detection educational efforts should be targeted to high-SES groups in areas of high UVR exposure. Contextual measures of both SES and UVR should be considered important determinants of melanoma occurrence in future studies.

Solar UV Radiation and Cancer in Young Children

“…Since our UVR exposure metric represents a 20 km buffer around the mother’s home we would not expect moves to be a strong source of exposure misclassification in this study and we would expect it to be nondifferential with respect to the outcome and likely biased estimates toward the null. Also, the increased melanoma risk in our study supports the validity of our exposure measure, as does the increased risk for melanoma in adults based on the same UVR exposure data for California in previous studies (24, 25). …”

“…Due to its diverse latitudes (32°30′ – 42° North) and elevations (282 ft below sea level in Death Valley to 14,494 ft at the peak of Mt Whitney), California receives a wide range of UVR. Other studies in California have linked similar UVR measures to increased risk for melanoma (24, 25) and reduced risk of non-Hodgkin’s lymphoma (22). …”

The impact of socio-economic status on health related quality of life for children and adolescents with heart disease

“…Although there have been significant limitations in using community-level geocodes for individual-level data [33,34], others have noted positive results from the use of geocodes [35,36]. If an SES measure can easily be developed with the use of geocodes and have as strong a predictive value as family income, researchers may have another SES tool with which to work.…”

Adulthood residential ultraviolet radiation, sun sensitivity, dietary vitamin D, and risk of lymphoid malignancies in the California Teachers Study

“…SES, in turn, is known to influence sun-related behaviors and cultural norms, such as vacation travel to sunny areas, routine outdoor recreational activities, and preferences for tanned skin. 45 Although we had detailed information on skin sensitivity to sunlight, the potential influence of skin type on UVR exposure is unclear, because lighter skin permits a higher level of vitamin D synthesis in response to a given amount of UVR exposure, 46 yet persons prone to sunburns might also take more precautions to avoid the sun. Indeed, our measure of sunburn blistering did not distinguish participants who were exposed but did not blister from participants who avoided sufficient exposure to cause blistering.…”