Skin Cancer Risk Reduction Behaviors Among American Indian and Non-Hispanic White Persons in Rural New Mexico

From 2008 to 2012, age-adjusted incidence rates of skin cancer for New Mexican non-Hispanic white males and females were 37.11 and 21.72, respectively.¹ The same rates for New Mexican American Indian males and females were 2.51 and 3.04, respectively. Despite this stark difference in incidence, half of all American Indian and Alaskan Native persons with skin cancer will die from the disease compared with less than one-sixth for all races combined.² This study sought to determine what sun-protective behaviors were used among rural New Mexican American Indian individuals, a relatively understudied population, and non-Hispanic white individuals, a relatively well-studied population.

A cross-sectional survey of 429 anonymous participants was conducted at community farmer and flea markets in 2 rural New Mexico/Navajo Nation border towns. This survey was conducted in English and completed by the participants; although English is a second language for many rural New Mexicans, it is commonly used. A multivariable logistic regression model of the probability of high skin-protective behavior was generated from covariates, including ethnicity, age, family history of skin cancer, sex, and eye color. A 2-sample t test was used to assess the difference in mean sun-behavior scores between American Indian and non-Hispanic white participants overall. Adjusted odds ratios (ORs) and their corresponding Wald 95% CIs were calculated. The University of New Mexico institutional review board approved the research. Participants provided oral consent; they were compensated with sunglasses and travel sunscreen.

The dependent variable, sun-behavior score, was constructed from eleven 5-point Likert-scale variables regarding skin-protective and risk behaviors. Sun behavior scores were dichotomized by their association with the overall median score of 36 points: scores of 36 or higher were classified as high skin-protective behavior, and scores less than 36 were considered low skin-protective behavior. A comparison of medians between American Indian and non-Hispanic white participants was also conducted via Wilcoxon tests on each of the eleven 5-point Likert-scale variables.

A higher proportion of non-Hispanic white participants used sunscreen, wore sunglasses, and had physician skin checks (P < .001) compared with American Indian participants. No significant differences were found for childhood sunburns, time spent outdoors, and use of shade, shirts with sleeves, or hats. Use of tanning beds was the least practiced behavior for both groups (median for both, 5 [indicating that tanning beds were never used]). American Indian participants were 38% less likely than non-Hispanic white individuals to have high sun-behavior scores (OR, 0.62; 95% CI, 0.37-1.04) (Figure 1). Women were 22% more likely than men to have high scores (OR, 1.22; 95% CI, 0.80-1.85). Participants with a family history of skin cancer were 45% more likely to have high scores compared with those without a family history (OR, 1.45; 95% CI, 0.82-2.58). Participants in individual age groups of 60 years or younger were less likely to have high scores compared with those older than 61 years (Figure 2).

Thirty years ago, Black and Wiggins stated, “there is virtually no information concerning sun exposure as to the life-style of the Southwestern American Indian that is other than anecdotal.”^3(p2901) This statement is still true. The brief behavioral inventory provided by this study may have useful data to enhance awareness projects and early detection practices among Southwestern American Indian individuals. In addition, the significantly lower frequency of physician skin checks reported by American Indian individuals (P < .001) in this study may be associated with the higher melanoma mortality rates among the American Indian population. Although there is a paucity of data for comparison, a similar study found non-Hispanic white people to be more likely than nonwhite individuals to have physician skin checks.⁴ Data from 1999 to 2006 showed high percentages of advanced, thicker melanomas among nonwhite compared with white persons.^4,5 The higher percentage of thicker and more advanced melanomas among minorities, including American Indian individuals,⁵ more often in non–sun-exposed skin, highlights the need for more effective melanoma awareness for all races and ethnicities in the United States as well as evaluation of etiologic differences. Although there remain insufficient data to support skin cancer screening, lack of awareness may play a role in later presentation for care and greater melanoma mortality.⁶ Our study underscores the importance of further assessment of the motivators and barriers to screening among Southwestern American Indian persons, a population at risk for thicker melanomas, poorer prognoses, and subsequently higher mortality rates.

Corresponding Author: Mary E. Logue, BA, University of New Mexico School of Medicine, 1416 C Vassar Dr NE, Albuquerque, NM 87106 (logueme@salud.unm.edu).

Accepted for Publication: July 15, 2016.

Published Online: September 14, 2016. doi:10.1001/jamadermatol.2016.3280

Author Contributions: Dr Berwick had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Study concept and design: Logue, Berwick.

Acquisition, analysis, or interpretation of data: Logue, Hough, Leyva, Kee.

Drafting of the manuscript: All authors.

Critical revision of the manuscript for important intellectual content: Logue, Berwick.

Statistical analysis: Hough, Leyva, Berwick.

Obtained funding: Logue, Berwick.

Administrative, technical, or material support: Logue, Berwick.

Study supervision: Berwick.

Conflict of Interest Disclosures: None reported.

Funding/Support: This study was supported in part by the Office of Academic Resources and Support, University of New Mexico School of Medicine.

Role of the Funder/Sponsor: The funding source had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Additional Contributions: William D. Tandberg, MD, and Fares Qeadan, PhD, contributed statistical advice, and Kimberly Page, PhD, provided analytic advice (all from the University of New Mexico). No financial compensation was given.