Latino Population and Clinical Trials: Improving the Informed Consent Process

By Maja Gawronska, MA

Latinos comprise 16 percent of the US population, and that number is expected to increase rapidly in the next few decades. Yet this fastest growing demographic is underrepresented in research studies, especially in clinical trials of new drugs and therapies.

In fact, Latinos account for only 7 percent of participants in research projects funded by the National Institutes of Health, and just 2 percent of those in clinical trials overseen by the Food and Drug Administration.

“Because of the underrepresentation of Latinos in clinical trials, it is extremely difficult to establish effective clinical guidelines for this population,” said Barton Palmer, PhD, professor of psychiatry at the UC San Diego School of Medicine and faculty member at the Stein Institute for Research on Aging. “This is a profound ethical and public health problem.

”In thirty years, Latinos are projected to account for nearly 20 percent of people older than sixty, but there is little data from Latinos on the efficacy of treatment and prevention of many diseases associated with aging. Previous studies have indicated that because of their greater propensity for obesity, this group might be at a higher risk of developing dementia and Alzheimer’s disease, which Latinos tend to get a couple of years earlier than the rest of the population. There are also many conditions that disproportionately affect Latinos, such as metabolic syndrome, a group of risk factors that increases the chance for heart disease and diabetes.

To further explore the underrepresentation of Latinos in medical research, Dr. Palmer partnered with Concepción Barrio, PhD, LCSW, associate professor at the USC School of Social Work and an expert on the interactions of ethnicity and clinical practice. Together they lead a $1.4-million, three-year project to study the process of informed consent and to develop a multimedia educational tool to enhance research literacy among Latinos.

This study will focus on patients with schizophrenia and schizoaffective disorder, a group which faces a risk for problems with understanding the informed consent process. But the findings are likely to be applicable to a broad range of clinical research,” said Dr. Palmer. Spanish-speaking Latinos are especially not well represented in research. This means that findings from most major drug trials for schizophrenia are being generalized to all populations, but they cannot really be generalized to Latinos,” added Dr. Barrio, who will also investigate the degree to which language, acculturation, education, health, and research literacy affect participants’ initial comprehension and satisfaction with consent procedures.

Language and cultural nuances are important in explaining the details of clinical trials, and lack of shared cultural knowledge might be a potential barrier to the participation of an ethnic minority in clinical trials and research studies. The lack of personal connection during recruitment might discourage potential participants, including many Latinos who tend to value relationship building very highly.

Researchers will test the effects of teaching participants about clinical research and the informed consent prior to discussing a specific protocol. “Informed consent is more than just a signature on a form. It involves education and information exchange that takes place between the researcher and the potential subject so that the subject is fully aware about what his or her participation entails,” said Dr. Palmer.

While the Latino population in the United States is often seen as homogenous, this group is diversified in terms of culture and overall health literacy. To address this misconception, the study will also consider possible subpopulation differences in the influence of language and other cultural factors on the informed consent process.

This project is funded by the National Institute of Mental Health.