UCLA

Chronic liver disease is increasingly prevalent with high rates of morbidity and mortality, yet it receives less attention than other similar chronic diseases such as cardiovascular disease and chronic obstructive pulmonary disease. Barriers to timely medical care may preclude diagnosis and management and thus, exacerbate potentially avoidable morbidity and mortality for persons with chronic liver disease. This dissertation explored the extent of health care barriers among adults with chronic liver disease compared to other chronic conditions and identified latent classes derived from different health care barriers to phenotype those at highest risk for recurrent acute care use within the adult population with chronic liver disease in the United States.

The first paper, “Evaluation of the Extent of Health Care Barriers among Adults with Chronic Liver Disease vs. Other Chronic Diseases in the United States,” compared estimates of any and the number of health care barriers and the association of recurrent acute care use by prevalence of barriers to care among adults with chronic liver disease versus those with cardiovascular disease and/or chronic obstructive pulmonary disease. Using a multivariable hurdle model, the study found that adults with chronic liver disease were significantly more likely to have any barriers to care (incident rate ratio, 1.12), but such a significant difference did not exist for the frequency of health care barriers. There was a dose-dependent relationship between likelihood of recurrent acute care use and prevalence of barriers to care. Inclusion of chronic liver disease as a high-risk group in future health policies that aim to improve access to care may help reduce challenges that persons with chronic liver disease encounter when seeking timely medical care and potentially reduce preventable acute care use.

The second paper, “Identification of Hidden Phenotypes Using Self-Reported Barriers to Care to Predict Risk of Recurrent Hospitalization or Emergency Department Visits among Adults with Chronic Liver Disease in the United States,” identified latent classes within the adult population with chronic liver disease using self-reported barriers to care and assessed each phenotype’s likelihood of recurrent acute care use. The best fitting model to the data included four latent classes or phenotypes: minimal barriers, unaffordability, care delays, and inability to establish care. The study used a multivariable multinomial logistic regression model to identify likelihood of class membership. The unaffordability phenotype was significantly associated with younger age, fair or poor health, functional limitation due to health, and uninsurance. Membership in the care delays class was significantly associated with Hispanics, fair or poor health, and functional limitation due to health. The inability to establish care phenotype was significantly associated with younger age, female sex, functional limitation due to health, and non-private insurance. The inability to establish care group had the highest odds of recurrent acute care use, followed by the care delays and unaffordability groups. An emphasis on risk stratification using health care barriers can potentially help improve interventions that aim to reduce recurrent acute care use among adults with chronic liver disease, particularly for those who struggle to establish care.

In summary, both chapters highlighted the prevalence of health care barriers and its association with recurrent acute care use for adults with chronic liver disease. Findings from the second chapter showed the consistent disparity in health care barriers for adults with chronic liver disease versus other chronic diseases and aimed to capture the attention of health policy makers to include chronic liver disease in future iterations of existing health policies or new programs that strive to improve outpatient care access to reduce preventable hospitalizations. The third chapter identified novel phenotypes of persons with chronic liver disease with different associated sociodemographic, health, and insurance characteristics and risks of recurrent acute care use. The third chapter also introduced the concept of using self-reported barriers to care as a way to risk stratify and allocate resources to the most vulnerable individuals with chronic liver disease. Both chapters intend to help improve health care access, reduce preventable acute care use, and potentially improve the morbidity and mortality trends among adults with chronic liver disease in the United States.