Abstract CN03-02: Community-based intervention to reduce liver cancer disparities in Asian Americans: A cluster randomized trial
Authors: Bastani Roshan , Glenn Beth A. , Herrmann Alison K. , Crespi Catherine M. , Wong Weng Kee , Jo Angela M. , Chang Cindy , Maxwell Annette E. , Taylor Vicky 
Published: January 2011

Asians experience the highest liver cancer incidence and mortality rates of all racial/ethnic groups in the U.S. Approximately 80% of liver cancers are etiologically related to chronic infection with the hepatitis B virus (HBV), which is endemic in Asia. It is therefore recommended that Asian adults first be tested for HBV to identify, counsel, and monitor virus carriers and that only those found susceptible be referred for vaccination. In light of the rapid growth and high interracial marriage rates of the U.S. Asian population, prevention and control of HBV infection through testing and vaccination is a critical public health priority.

Koreans have the highest liver cancer incidence and mortality rates in Los Angeles County, home to the largest concentration of Koreans in the U.S. To date, no intervention studies have focused on HBV prevention and control among Korean adults. Therefore, we conducted a cluster randomized trial to test the effectiveness of a culturally-tailored small group intervention in increasing HBV serologic testing rates in a community sample of Korean adults in Los Angeles. The sample was recruited through churches, given the large proportion of Korean Americans that attend church.

Methods: Study Design. A 2-group design, with cluster randomization at the church level, was used. Churches (N=50) were stratified by size (small: 50-200 members, medium: 201-900 members, large: 900+ members) and geographic location (Koreatown vs. outside Koreatown). Randomization was conducted within each stratum. The intervention consisted of a 1-hour discussion session on HBV, using an interactive, nondidactic format, aided by PowerPoint materials and take-home materials. The control group received a 1-hour discussion session, using a similar format, on nutrition and physical activity (NPA) as well as take-home materials. Lay health educators served as facilitators for the discussions in both study conditions.

Church members were recruited on site, in conjunction with routine weekend church services, and invited to participate in a discussion on cancer prevention. Participants had no advance knowledge of their church's study condition assignment. Eligibility criteria included: Korean ethnicity, age 18-64 years, and no prior history of HBV testing. Individuals previously tested, but unaware of their results, were also eligible. Baseline surveys were administered in person, by interviewers, immediately prior to discussion sessions. Subjects were contacted by telephone 6 months post-intervention to assess study outcomes.

Theoretical Framework. The Health Behavior Framework (HBF) guided the interventions and data collection instruments.1 The HBF is a comprehensive conceptual framework that includes individual, health system, community, and societal level variables that can influence health behavior. The focus of this trial was primarily on modifying individual (e.g., knowledge, health beliefs) and community level (e.g., social norms) constructs. Data Collection Instruments. Data collection instruments assessed HBF constructs including demographics, cultural factors and knowledge, beliefs, barriers, and supports related to HBV and NPA. To assess the effect of answering a lengthy survey (testing effect) on HBV testing, approximately half the sample completed an abbreviated baseline interview.

Results: Recruitment. To date (7/31/10) 1,826 individuals have been screened at 50 churches, and 1174 (64%) were eligible for the study participation. Ninety-four percent (N = 1105) of those eligible were enrolled into the trial (target enrollment =1200). The vast majority of participants completed baseline interviews in Korean (98%) and attended their assigned session (92%). Among participants due for 6-month follow-up (N = 972), the retention rate in both study conditions was 86%.

Demographic Characteristics of Sample. Nearly all participants were born in Korea (97%), with an average stay in the U.S. of 16 years and a mean age of 45.5 years. Participants were well-educated (54% have a college degree or more) with a wide range of incomes (25% earn less than $30,000 and 23% earn more than $80,000). Still, only 42% were insured and only 49% indicated that they had a usual place where they sought health care. Knowledge and Beliefs Regarding HBV. Results of HBV baseline survey items from participants assigned to complete the full-length baseline interview (N = 557) illustrate gaps in knowledge related to HBV. For example, while 77% were aware that HBV can be spread by an infected individual who feels and appears healthy, only 45% knew that the virus can be sexually transmitted. Fifty-two percent believed HBV can be transmitted via sharing food and eating utensils and 40% believed that it can be transmitted via coughing or sneezing.

Health beliefs that may influence testing likelihood were also identified. Only 58% believed that Koreans were more susceptible to HBV than Caucasians. A majority of participants (82%) believed that HBV can be treated, but only 49% were aware that infection can last a lifetime. Perceived efficacy of HBV testing in preventing future liver problems was high (93%). Additionally, 47% believed that people avoid those infected with HBV, suggesting a stigma in the community related to HBV.

Intervention Effect. We investigated the effect of the intervention on receipt of HBV serologic testing in the overall study sample, and within strata defined by church size and location. We employed intent-to-treat analyses in which individuals lost to follow-up were counted as untested. A statistically significant intervention effect was detected in the overall sample (OR=4.6, p&lt;.001). At follow-up the testing rate was 20% in the intervention group versus 6% in the control group. Significant effects were also observed within small (OR = 5.2, p&lt;.01), medium (OR=5.9, p=.001), and non-Koreatown (OR=8.5, p&lt;.001) churches.

Discussion: This study illustrates the need for liver cancer prevention and control efforts in the Korean American community, and the viability of the church as an intervention setting. Although participants were from Korea, where HBV is endemic, baseline data revealed significant gaps in knowledge related to the virus.

Our small-group intervention was successful in increasing HBV testing rates. However, a significant intervention effect was not detected in large or Koreatown churches. This could be due to the fact that free HBV testing events (sponsored by a community organization) were conducted in control churches in these two strata during our study period.

While the intervention produced a fairly large and statistically significant effect size, the absolute HBV testing rate in the intervention group was only 20%. This has implications for the value of such an intervention when applied at the population level. Further efforts are needed to test interventions that can substantially increase HBV testing among high-risk groups.

Reference:

1. Bastani, R., Glenn, B.A., Taylor, V.M., Chen, M.S., Nguyen, T.T., Stewart, S. L., Maxwell, A.E. (2010). Integrating theory into community interventions to reduce liver cancer disparities: The Health Behavior Framework, Preventive Medicine, 50 (1-2):63-7. Epub 2009 Aug 27

Citation Information: Cancer Prev Res 2010;3(12 Suppl):CN03-02.