UCLA

This dissertation evaluates the national burden of heart failure (HF) hospitalizations. HF is the leading cause of admission among all cardiovascular conditions. Yet, information is lacking on the factors associated with hospital expenditures, differences in utilization by gender and ethnicity, and the complexity of hospitalized patients. Due to an aging demographic, the prevalence of HF is projected to continue to increase in the future. This dissertation is divided into three projects that describe different aspects of hospital utilization for heart failure.

The National Inpatient Sample (NIS) provided through the Healthcare Cost and Utilization Project (HCUP) were used for all three projects. The NIS datasets were obtained for the years between 2002 and 2013. Each year of the NIS contains a sample of 7 to 8 million hospital discharges representing 20% of all hospitalizations nationally. The NIS is the largest all-payer database that uses administrative data to estimate hospital utilization nationally.

The first project describes the factors associated with hospitalization costs in the highest quantile compared to the lowest quantile. Hospital cost data was estimated based on charges using established conversion methods. A multinomial logistic model adjusted for patient and hospital factors as well as sampling strategy was used to identify factors associated with higher cost hospitalizations. Select patient demographics and comorbidities were associated with the highest hospitalization costs. When controlling for all patient related factors, hospital characteristics and region were still associated with higher hospitalization costs.

The second project reports on the trends in age-standardized hospital utilization by gender and ethnicity. Shifting age demographics make reporting trends in crude hospitalization rates inaccurate. The purpose of this research project was to standardize hospital utilization rates and contrast them by gender and ethnic subgroups. The difference in hospital utilization rates for men has increased relative to women. The difference in hospital utilization for blacks is nearly two and a half times that of whites and the relative difference has not changed over the recent decade. Hispanics have lowered their hospital utilization rates for HF. Asians have consistently had the lowest HF hospitalization burden.

The third project describes the shifts in comorbid conditions among hospitalized HF patients. While research attention has focused on reducing repeat HF admissions, shifts in the complexity of care for HF patients have not been described. Over the last decade, diabetes, obesity, and renal disease have increased in prevalence among hospitalized HF patients. Average Elixhauser comorbidity scores have increased for all gender and ethnic groups. The severity of comorbid illnesses among HF patients continues to increase, prompting the need for more effective management of these complex patients.