Genetic testing may not trigger more use of health services

(Press-News.org) SEATTLE—People have more and more chances to participate in genetic testing that can indicate their range of risk for developing a disease. Receiving these results does not appreciably drive up— or diminish—test recipients' demand for potentially costly follow-up health services, according to a new study in the May 17, 2012 early online issue of Genetics in Medicine.

The study was done by researchers with the Multiplex Initiative, a multi-center collaborative initiative involving investigators from the National Institutes of Health's Intramural Research Program, Group Health Cooperative in Seattle, and the Henry Ford Health System in Detroit.

The tests are available from a growing number of commercial producers, and health care providers have been uncertain whether people who received information only about risk would follow up by demanding diagnostic testing to check for predicted illnesses.

The study is the first to use electronic health records—rather than self-reported behavior—to measure the impact of genetic testing on the subsequent use of health services by commercially insured, healthy adults. Self-reports, which can be affected by memory lapses and other problems, tend to be less accurate.

"Our study was a best-case scenario, because we chose 15 genes reliably associated with relatively small risks for eight common diseases that health behaviors can affect," said the study's first author Robert J. Reid, MD, PhD. Dr. Reid is Group Health's associate medical director of research translation and an associate investigator at Group Health Research Institute. Those diseases were type 2 diabetes, coronary heart disease, high blood cholesterol, hypertension, osteoporosis, lung cancer, colorectal cancer, and melanoma. "We hope that testing positive activates patients to make behavior changes that could lower their risk, such as quitting smoking," he added, "without causing them to make many extra visits to their doctors."

"Understanding personalized genetic information is important because it is becoming more readily available and we need to figure out how to integrate it effectively and efficiently into the clinical care we provide," said coauthor Eric B. Larson, MD, MPH, Group Health Cooperative's vice president for research and Group Health Research Institute's executive director.

"There are a lot of unanswered questions about how genetic test results can be used to guide people toward making positive lifestyle and health behavior changes," said Colleen McBride, PhD, chief of the Social and Behavioral Research Branch at the National Human Genome Research Institute (NHGRI). "This study goes a long way toward bringing data to these debates and shows that people are not likely to make inappropriate demands of health delivery systems if they are properly informed about the limitations of genetic tests."

Genetic tests, such as those used in this study, can detect common variants of genes associated with modest changes in the chances of developing particular diseases. "Multiplex" means simultaneously performing many genetic tests on one blood sample.

"Good next steps would be to see whether any patients were motivated to make long-term behavior changes—and whether those individuals at highest risk went to their doctors more often," Dr. Reid said. "But this study wasn't designed to answer those questions."

The study included 217 healthy people age 25 to 40 who elected to participate in genetic susceptibility testing that their health plan offered. The researchers analyzed the participants' health care use in the 12 months before genetic testing and the 12 months after it. They also compared the test group's health care use with that of about 400 similar plan members who declined the testing offer.

The researchers counted the doctor visits, lab tests, and procedures the people received, particularly those services associated with four of the eight conditions that the multiplex panel tested. Most of the procedures or screening tests that were counted are not among those currently recommended for people in this age group who don't have symptoms. The researchers found that participants in genetic testing did not change their overall use of health care services compared with those not tested.

Each person who chose to undergo the multiplex test was found to carry at least one at-risk genetic marker. Individuals in the population carried an average of nine at-risk variants. Having a risk version of one of the 15 genes on the multiplex genetic test does not mean that a person is certain to get the condition—only that he or she might have a slightly greater chance of developing the health condition. Many things other than genetics contribute to the risk of common diseases, including such lifestyle factors as diet, exercise, smoking, and sun exposure.

"Much is written about using genetics to personalize health care," said co-author Lawrence C. Brody, PhD, chief of NHGRI's Genome Technology Branch. "Some think this new generation of genetic tests will be a very positive addition to medicine; others believe they have the potential to make things worse." Dr. Brody designed the panel of genetic tests used in the Multiplex Initiative.

The NHGRI Division of Intramural Research and the National Cancer Institute, both at NIH, along with Group Health Cooperative in Seattle and the Henry Ford Health System in Detroit, launched the Multiplex Initiative in May 2007. For the first two years of the study, the investigators accumulated data from 2,000 Detroit area residents who were offered a multiplex genetic test for eight common conditions.

Once enrolled, participants were asked to review information online about the multiplex genetic test and to decide whether they were interested in taking the test. Those who agreed to genetic testing met with a research educator, who provided more information about the risks and benefits of testing and obtained the patient's written consent. Test results were mailed to participants. Trained research educators called the participants to help them interpret and understand their results. The study also included follow-up interviews with participants three months after they received their results.

###This work was supported by the Intramural Research Program of the National Human Genome Research Institute, National Institutes of Health. The research was also made possible by collaboration with the Cancer Research Network, funded by the National Cancer Institute. Group Health Research Institute and Henry Ford Hospital provided additional resources. Funded through a federal contract from the National Institutes of Health to The Johns Hopkins University, the Center for Inherited Disease Research provided genotyping services.

In addition to Drs. Reid, Larson, McBride, and Brody, the Multiplex Initiative study team included Andy Baxevanis, PhD, an associate investigator in NHGRI's Genome Technology Branch; and Sharon Hensley Alford, PhD, MPH, an epidemiologist at the Henry Ford Health System.

For more information about the Multiplex Initiative, see http://multiplex.nih.gov.

National Human Genome Research Institute The National Human Genome Research Institute (NHGRI) is one of the 27 institutes and centers at the National Institutes of Health, an agency of the Department of Health and Human Services. The NHGRI Division of Intramural Research develops and implements technology to understand, diagnose, and treat genomic and genetic diseases. For more information, see www.genome.gov.

National Institutes of Health The National Institutes of Health (NIH), the nation's medical research agency, includes 27 institutes and centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information, see http://nih.gov.

HMO Research Network Now 19 members strong, the HMO Research Network is a group of research centers associated with health care delivery systems. They collaborate on multi-site studies in real-world settings where people receive everyday care. With the ability to pool information on more than 16 million people, Network researchers gain statistical power and ethnic and geographical diversity. Since 1994, Network studies have been answering pressing questions about what really works—and what doesn't—to keep people healthy and to deliver care effectively. For more information, see http://hmoresearchnetwork.org.

Cancer Research Network The HMO Cancer Research Network (CRN) consists of the research programs, enrolled populations, and data systems of 14 health maintenance organizations nationwide that are part of the HMO Research Network. The overall goal of the CRN, and the National Cancer Institute initiative under which it was funded, is to use this consortium of delivery systems to conduct research on cancer prevention, early detection, treatment, long-term care, surveillance, and cancer communication and dissemination and implementation research. A portfolio of research studies encompasses cancer control topics ranging from modification of behavioral risk factors such as smoking to cancer care at the end of life. Through this expansive program of research, the CRN seeks to improve the effectiveness of preventive, curative, and supportive interventions for both major cancers such as breast, colon and lung, and rare tumors. The CRN is also uniquely positioned to study the quality of cancer care in community-based settings. As a reflection of its commitment to improving quality of care, the Agency for Healthcare Research and Quality is cooperatively supporting the CRN with the NCI. For more information, see http://crn.cancer.gov.

Henry Ford Health System Henry Ford Health System is a not-for-profit corporation comprising hospitals, medical centers, and one of the nation's largest group practices. Researchers across multiple research centers within Henry Ford Health System participate in the HMO Research Network. The health system is an integrated health care system serving more than 800,000 patients and health plan members in Southeast Michigan. Approximately 35 percent of the HFHS patient population is African American, creating special opportunities for research and quality improvement in the area of health care disparities. For more information, see http://henryford.com.

Group Health Research Institute Group Health Research Institute is the research arm of Seattle-based Group Health Cooperative, a consumer-governed, nonprofit health care system. Founded in 1947, Group Health Cooperative coordinates health care and coverage. Group Health Research Institute changed its name from Group Health Center for Health Studies in 2009. Since 1983, the Institute has conducted nonproprietary public-interest research on preventing, diagnosing, and treating major health problems. Government and private research grants provide its main funding. For more information, see http://grouphealthresearch.org.