UCLA

ABSTRACT OF THE DISSERTATION

Factors Affecting Medication Adherence among Vietnamese Immigrants

with Latent Tuberculosis Infection: A Mixed Design

by

Fayette Nguyen Truax

Doctor of Philosophy in Nursing

University of California, Los Angeles, 2016

Professor Adeline M. Nyamathi, Chair

Completion of latent tuberculosis infection (LTBI) treatment among foreign-born Asians in the United States (US) is suboptimal, thus leading to high rates of reactivation tuberculosis (TB) among this population. Approximately 77% of TB cases in the US are from reactivation TB and foreign-born Asians have a higher reactivation rate compared to Blacks, Hispanics and Whites. In Orange County (O.C.), the annual TB case rate continues to remain steady at 6.0 cases per 100,000 in 2014 with foreign-born persons from Vietnam leading with a TB rate of 49.7%, Mexico at 14.4% and the Philippines at 12.6%. Overall the high number of active TB cases among Vietnamese immigrants, coupled with low LTBI treatment completion rate of approximately 50.1% in the overall Asian population, presents an important challenge to the national strategy of eliminating TB (Li et al., 2010). At this time, there is limited data on Vietnamese immigrants with LTBI in the US.

The purpose of this mixed methods study is to identify the factors related to LTBI treatment acceptance and completion in addition to exploring the decision-making process of LTBI treatment adherence among Vietnamese immigrants. Predictors for phase 1 included: socio-demographic characteristics, basic health history, behavioral survey scores measured by Morisky Medication Adherence Scale (MMAS-8), Champion Health Belief Model Scale (CHBMS-29) and the Self-Efficacy for Appropriate Medication Use (SEAM-9). Significant predictors for multivariate analysis for treatment acceptance included individuals with a history of smoking and recent contact with an infectious TB case. For treatment completion, the top two most significant predictors in the univariate analysis included age group between 18-44 years and current employment. No significant predictors were identified in the multivariate analysis for treatment completion. There were also no significant correlations identified between the psychosocial measurements (SEAM-9, CHBMS-29, MMAS-8) and treatment completion.

In phase 2, a decision-making grounded theory model entitled “The Decision-Making Model for Latent TB Infection Treatment Acceptance and Completion” was developed from the stories and testimonies of 17 Vietnamese participants. Three primary decision-making points were identified that was critical to the development of the proposed model: treatment acceptance, treatment initiation and treatment completion. Three categories emerged from participants’ data that were directly related to the decision to accept LTBI treatment, “beliefs”, “TB awareness” and “trust in healthcare”. Findings revealed the only category to influence treatment initiation was “barriers” to scheduling. Lastly, the decision to maintain adherence and complete treatment were strongly influenced by self-determination, medication side effects, and having family support.

Based on this study’s findings, target screening of Vietnamese immigrants at highest risk for latent TB reactivation should be done more frequently in private community clinics and focus on reducing barriers to treatment acceptance, initiation and completion.