Volume
8: No. 5, September 2011
Ana Patricia Ortiz, MPH, PhD; Magdalena López, MS; Libertad T. Flores, MPH; Marievelisse Soto-Salgado, MS; Lila J. Finney Rutten, PhD, MPH; Ruby A. Serrano-Rodriguez, MS, DrPH; Bradford W. Hesse, PhD; Guillermo Tortolero-Luna, MD, PhD
Suggested citation for this article: Ortiz AP, López M, Flores LT, Soto-Salgado M, Finney Rutten LJ, Serrano-Rodriguez RA, et al. Awareness of direct-to-consumer genetic tests and use of genetic tests among Puerto Rican adults, 2009. Prev Chronic Dis
2011;8(5):A110.
http://www.cdc.gov/pcd/issues/2011/sep/10_0220.htm. Accessed [date].
PEER REVIEWED
Abstract
Introduction
Genetic testing remains low among racial/ethnic minority populations in the United States. We aimed to determine
the prevalence and correlates of awareness of direct-to-consumer (DTC) genetic tests and the prevalence of genetic test use in a population-based sample of adults in Puerto Rico.
Methods
We analyzed data from adults aged 18 years or older who completed information on genetic test awareness (n = 611; 96% of study population) from the Health Information National Trends Survey conducted in Puerto
Rico in 2009. Odds ratios with 95% confidence intervals were estimated by using
logistic regression models to identify factors associated with awareness of
DTC genetic tests.
Results
The majority of respondents (56%) were aware of direct-to-consumer genetic tests, and
approximately 4% had ever undergone any genetic test. Respondents who had never been married were less likely to be aware of
DTC tests, as were current smokers. Respondents who ever sought cancer information were more likely to be aware of these tests.
Conclusion
We provide the first published data on the awareness of DTC genetic tests and on use of genetic testing in Puerto Rico. Forty-four percent of our sample of Puerto Rican adults
were unaware of direct-to-consumer genetic tests. Given the lack of clear benefits of DTC genetic tests to the general population, educational interventions should be developed to increase awareness and specific knowledge regarding the appropriate use of DTC genetic tests among people who
are already aware of their existence.
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Introduction
With the completion of the Human Genome Project (1), genetic tests have increasingly become available to the population. Genetic testing is defined as “the analysis of human DNA, RNA, chromosomes, proteins, and certain metabolites in order to detect heritable disease-related genotypes, mutations, phenotypes, or karyotypes for clinical purposes” (2). Genetic tests that target specific diseases, such as cancer, are offered in health care settings to identify people with increased disease risk,
for example, because of family history (3). The American Society of Clinical Oncology recognizes that identifying people at highest risk for cancer may improve prevention and early detection efforts and therefore supports access to genetic testing for all people with apparent heredity risk for cancer (4). In addition, the general public, patient groups, and people with a family history of cancer (5-7) appear to be strongly interested in genetic testing.
Despite increasing availability and public interest, studies on genetic testing are few, and most have focused on specific cancer types, as disease-specific tests have become more available in recent years. Previous research suggests that not all sociodemographic groups have
benefited equally from genetic counseling and testing for cancer susceptibility (8); their use has been documented to be lower among racial/ethnic minority populations compared with non-Hispanic whites (8,9). Among
African Americans, studies of diverse groups in the medical setting, including women seeking general medical services (10), cancer patients (11), and people with
a family history of cancer (12), have established consistently low levels of awareness of genetic testing for early identification of cancer risk compared with non-Hispanic whites. Although studies of genetic testing specifically among Hispanics are few, analyses reveal low levels of awareness and use of genetic cancer screening
(8,9,11), much of which has been shown to be related to education levels, nativity, or length of residence in the United States (8,13).
Genetic tests are increasingly being offered as direct-to-consumer (DTC)
services through the Internet and other venues, providing people access to these tests without the involvement of a health care professional (14,15). For example, nutrigenomic testing, which involves testing for genes associated with common diseases, is becoming increasingly common; these results are used, together with information on diet and lifestyle habits provided by the test subject, to assess potential health risks and
inform recommendations on behavioral changes, diet, or nutritional supplements (14-16). Of concern and of potential harm to consumers are 1) limited regulations and guidelines
for pretest and posttest counseling, 2) inconsistencies in the accreditation of the laboratories involved, and 3) inconsistencies in medical advice regarding interpretation of results (14). In addition, a report by the US Government Accountability Office (GAO) highlighted concerns about nutrigenomic tests, stressing
that such tests may mislead consumers by making vague predictions about their health risks (17). A more recent report from the GAO also highlights concerns about DTC genetic tests (18), including deceptive marketing of the capacities of such tests, lack of standardization across companies, and erroneous advice, concluding that test results are misleading and of little use to consumers. For example, given that companies test for different risk markers, different companies may provide different
results regarding disease risk for the same person. In addition, because prevalence of genetic variants may differ by population or ancestry, it is not clear how different tests may benefit people from different racial/ethnic minority populations (18) or admixed populations, such as Puerto Ricans. Furthermore, the tests poorly predict disease risk and may not account for gene-gene interactions and gene-environment interactions.
Demographic differences between people who are aware of and use genetic tests have been observed for both DTC tests and for tests administered in clinical settings (13,14,19); such differences may contribute to health disparities among population subgroups. Information on public awareness, interest, or use of genetic tests is generally limited and is nonexistent for the population of Puerto Rico. This information is necessary to better understand public demand for these tests and will
provide baseline data to track consumer awareness of and demand for DTC genetic tests. In addition, better knowledge is necessary to develop educational interventions, increase awareness, and improve decision making about these tests. Given the limited data on genetic testing among Hispanic populations and the lack of data for Puerto Rico, our study aimed to determine the prevalence and correlates of DTC genetic test awareness and the prevalence of genetic test use in a population-based sample
of adults surveyed for the Health Information National Trends Survey (HINTS) conducted in Puerto Rico in 2009.
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Methods
Study design and study population
We performed a secondary data analysis from a sample of adults aged 18 years or older who participated in the cross-sectional 2009 HINTS survey conducted in Puerto Rico (HINTS-PR). Data collection procedures for the 2009 HINTS-PR survey have been described in detail elsewhere (20). In brief, the 2007-2008 HINTS survey used for the mainland HINTS data collection (21) was fielded in Puerto Rico from April to June 2009, through the Puerto Rico Behavioral Risk Factor Surveillance System telephone research center. Data were collected via random-digit dialing and a computer-assisted telephone interview system; the stratified sampling frame represented 8 geographic regions
designated by the Puerto Rico Department of Health. Within each stratum, sampled telephone numbers were selected with equal probability. Nonworking and nonresidential numbers were eliminated from the sample. Trained bilingual Puerto Rican interviewers collected 639 interviews from 837 households screened (weighted extended interview response rate, 76%). Of these, 611
respondents (96%) provided complete information on DTC test awareness and were included in our analysis. All of these 611
respondents also had complete information on age and sex, and although 2 were missing information on genetic test use,
their data were retained for the study.
The main outcome variables included in our analysis were awareness of DTC genetic tests and use of genetic tests, assessed with the following questions: “Genetic tests that analyze your DNA, diet, and lifestyle for potential health risks are currently being marketed by companies directly to consumers. Have you heard or read about these genetic tests?” and “Have you ever had a genetic test?” Study covariates included demographic characteristics such as age, sex, education, marital status, and
employment status. Information on health insurance coverage and personal and family history of cancer was also assessed. Other covariates of interest included body mass index, daily consumption of 5 or more servings of fruit or vegetables, and having a regular health care provider. Current smokers were defined as people who had smoked at least 100 cigarettes in their lifetime and continued to smoke at the time of the interview.
We also assessed information about health, cancer-specific
information seeking, and sources of information. Respondents were asked, “Have you ever looked for information about health or medical topics from any source?” and “Have you ever looked for cancer information from any source?” Respondents who sought health or cancer information were asked to identify the source: “The most recent time you looked for information about health or medical topics, where did you go first?” Responses were categorized into 4 groups: Internet, printed
materials (eg, brochures, pamphlets, newspapers, books), health care professionals, and other (eg, interpersonal contact, TV, radio, telephone, health organizations).
Data analysis
All analyses were weighted to estimate standard errors of point estimates for the complex survey data
by using jackknife repetition as an estimator. Data were weighted according to total estimates of sex, age, education, and marital status obtained from the American Community Survey for Puerto Rico (20) to provide representative estimates of the adult population in Puerto Rico. We calculated descriptive statistics for all variables included in this analysis. We conducted bivariate analysis to
assess potential associations between demographic, health, and behavioral
characteristics of respondents and awareness of genetic tests by using the Pearson χ2 test. On the basis of the results of the bivariate analysis, we constructed a multivariate logistic regression model to estimate odds ratios and their 95% confidence intervals for the association between covariates of interest and genetic test awareness. Interactions and goodness of fit of the model were tested with the
likelihood ratio test and the Hosmer-Lemeshow test, respectively.
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Results
The majority of respondents (56%) were aware of DTC genetic tests, and
approximately 4% had ever used any genetic test (Table 1). Lower awareness of DTC genetic tests was observed among men, single
people, smokers, and people who had never sought health or cancer information
(Table 2). Among people who were aware of genetic tests (n = 361), those who had ever looked for cancer information (n = 122) sought this information mostly via the Internet (47%), printed materials (28%), or through health care
providers (16%). A similar pattern was observed for general health information seeking (data not shown).
We found no significant interactions in the multivariate model and a good model fit (Hosmer-Lemeshow test: χ2 = 2.50; P = .96). Awareness of DTC genetic tests was independently associated with marital status: people who were married or living together and those who were divorced, separated, or widowed were more likely to be aware of genetic tests
than people who were never married. Current smokers were less likely than nonsmokers to be aware of genetic tests, and
respondents who had ever looked for cancer information were more likely to have heard or read about DTC genetic tests than those who had not
(Table 3).
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Discussion
Although our result for awareness of DTC genetic tests (56%) was higher than that reported in the United States in the 2006 HealthStyles Survey (14%) and for Hispanic (25%) and non-Hispanic (30%) respondents in the 2008 US HINTS (overall prevalence, 29%) using the same survey item (14,22,23), the lack of awareness in our sample was nevertheless high. Meanwhile, use of genetic tests in Puerto Rico (4%) was higher than that reported in the United States by the 2006 HealthStyles
National Survey 1%, but lower than that reported in the 2008 US HINTS survey overall 8% and for Hispanic 9% and non-Hispanic respondents 8%. Although causal attributions cannot be established from these data, the higher awareness and use of genetic testing observed in Puerto Rico relative to mainland estimates coincides with more marketing and availability of such tests over time (24).
Similar to what has been seen in the US mainland (14), instead of health care professionals, the Internet was the primary source of information for DTC tests in our study. This source of information is of concern because a systematic analysis of websites promoting nutrigenomic services in 2006 showed that organizations that either sold or promoted these tests did not provide adequate information about nutrigenomic services and at-home genetic testing in terms of laboratory certifications,
test validity or utility, or genetic counseling (16).
Even though this lack of professional information could be because limited data are available to support the products currently on the market (14), the rapid growth in the availability of health-related DTC genetic tests
offers an opportunity for professional organizations to develop and promote their posture regarding the use of these tests and highlights the need for the development of consistent recommendations (15); these measures will support the tests’ appropriate use as more data become
available. Clinicians should advise their patients that currently available testing has
little value for disease risk ascertainment but should use the opportunity to direct patient counseling toward modifiable risk factors, such as tobacco cessation (25). Government regulation regarding the use of these technologies will also be essential (26).
Consistent with the results of our study, previous research from US HINTS has identified a positive relationship between health information seeking and genetic test awareness (23). Whereas, although the 2006 HealthStyles data revealed a higher prevalence of genetic test awareness among respondents younger than 65 years and those with at least a high school education, neither age nor education were associated with awareness of genetic tests in Puerto Rico. Neither our study nor the study by
Goddard and colleagues (14) identified significant associations between sex or family history of cancer and test awareness. Similar results have been observed for Hispanics in the 2000 and 2005 National Health Interview Survey, specifically for genetic testing for increased cancer risk (13,27). However, these findings are inconsistent with research reporting more awareness and use of genetic tests among women and people with a family history of cancer (5-9). For family history, the lack of
association could be explained by the low proportion of people in our study with family history of cancer (low statistical power).
Meanwhile, the association between smoking status and awareness of DTC genetic tests is particularly interesting given that this group is at an increased risk of multiple chronic diseases and could be a group that benefits from DTC testing in the future, if the benefit of testing is established.
Health disparities exist in cancer occurrence by race/ethnicity (28). Some of these disparities may be explained by differences in lifestyle and environmental or genetic risk factors across populations. Although we do not focus our analysis on genetic testing specifically for cancer risk, genetic cancer screening may provide needed motivation and opportunities for prevention because people with basic knowledge about inherited cancer risk and awareness of genetic testing for cancer
susceptibility mutations may make more informed choices about their health care services (27). Although Puerto Ricans living in the United States show the highest level of awareness of genetic testing for cancer risk compared with other Hispanic subgroups (13,27), socioeconomic and racial/ethnic disparities in use of genetic counseling and testing for cancer susceptibility continue to exist (8,9,19). One explanation for the lower awareness and use of genetic tests for cancer risk in
racial/ethnic minority populations, particularly Hispanics, is that they are less exposed to health information through the health care system partially because of language barriers (8). Low awareness about genetic testing among Hispanics may increase cancer disparities in this group (29). Thus, to guard against the possibility of tests becoming a source of health disparity (29), DTC and cancer-specific genetic tests that have proven health benefits in the future should be made equally
available to all who might benefit from them.
Our study is subject to limitations. First, because HINTS-PR was a telephone-based survey, it includes data only from residents who have a working
landline telephone. Consequently, our data may not be generalizable to the entire adult Puerto Rican population. Nonetheless, the weighted extended interview response rate in the 2009 HINTS-PR (76.4%) was higher than that reported for the 2007 US HINTS (60.4%) (30). Second, the prevalence estimates were based on self-reported information, which
is subject to recall and social desirability biases. Third, the small number of
respondents who had used genetic tests did not permit us to explore correlates of this behavior. Finally, our estimates of awareness of DTC tests and use of genetic tests may be inaccurate if respondents did not fully understand or misinterpreted the study questions. In fact, even though the research question used to determine DTC genetic test awareness included a brief explanation of these tests, some
people may not understand what a genetic test is; this clarity issue should be carefully addressed in future studies.
To our knowledge, this study provides the first published data on the awareness of DTC genetic tests and use of genetic tests in Puerto Rico. These baseline data are valuable for tracking trends in awareness of DTC tests and use of genetic tests in Puerto Rico and can inform the development of policy and educational efforts regarding the appropriate use of these tests. We expect that the proportion of people who are aware of and use these tests will continue to increase, as more of these
tests become available, as their marketing increases, and as the Internet and other sources of information become more widely available to the general population. Given the lack of clear benefits of DTC genetic tests to the general population, educational interventions should be developed to increase awareness and specific knowledge regarding the appropriate use of DTC genetic tests among people who are already aware of their existence (primary audience). As a clear message
about these tests is in circulation, people who are unaware (secondary audience)
may start to become more adequately aware of them. Future studies should try to elucidate remaining questions in this area of genetic testing, such as the prevalence of disease-specific genetic testing in clinical settings, and other psychosocial correlates of genetic testing awareness, including attitudes, beliefs, and cultural or religious norms regarding their use.
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Acknowledgments
This project was supported by contract no. HHSN261200800001E from the National Institutes of Health, National Cancer Institute; no. 5R25CA094186-08 from the National Institutes of Health, National Cancer Institute: Training in Computational Genomic Epidemiology of Cancer; nos. U54CA96297 and U54CA96300 from the University of Puerto Rico-MD Anderson Cancer Center, Partnership for Excellence in Cancer Research; no. G12RR03051 from the Research Center of Minority Institutions, University
of Puerto Rico; and no. U50/325128-02 from the Centers for Disease Control and Prevention, Hispanic-Serving Health Professions School.
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Author Information
Corresponding Author: Ana Patricia Ortiz, MPH, PhD, Department of Biostatistics and Epidemiology, Graduate School of Public Health, Medical Sciences Campus, University of Puerto Rico, PO Box 365067, San Juan, PR 00936-5067. Telephone: 787-772-8300, ext 1204. E-mail:
ana.ortiz7@upr.edu. Dr Ortiz is also affiliated with the University of Puerto Rico Comprehensive Cancer Center, San Juan, Puerto Rico.
Author Affiliations: Magdalena López, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; Libertad T. Flores, Alpert Medical School of Brown University, Providence, Rhode Island; Marievelisse Soto-Salgado, University of Puerto Rico, San Juan, Puerto Rico; Lila J. Finney Rutten, SAIC-Frederick, Inc, National Cancer Institute, Frederick, Maryland; Ruby A. Serrano-Rodriguez, Puerto Rico Department of Health, San Juan, Puerto Rico; Bradford W. Hesse, National Cancer
Institute, Bethesda, Maryland; Guillermo Tortolero-Luna, University of Puerto Rico Comprehensive Cancer Center, San Juan, Puerto Rico.
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