to another, due to pricing differences between years. This study used data from 2002,

which was the most recent data available at study onset. This study combined previous

years with 2002 data and prices of the previous years were inflated to reflect 2002 rates.

 Research Questions

Research Question 1

 After controlling for demographic characteristics, comorbidities, insurance status,

and perceived mental and physical health status, do pulmonary and cardiac patients with

comorbid depression or anxiety have higher health care expenditures than those with

pulmonary or cardiac conditions alone? The specific aim is to determine if, and to what

extent, depression or anxiety increases health care expenditures in pulmonary or cardiac

patients. The hypothesis is that the presence of depression or anxiety will correspond to

an increase in health care expenditures.

Research Question 2

 After controlling for demographic characteristics, comorbidities, insurance status,

and perceived mental and physical health status, do pulmonary and cardiac patients with

comorbid depression or anxiety who received mental health treatment have lower health

care expenditures than those patients who did not receive mental health treatment? The

specific aim is to determine if, and to what extent, the treatment of depression or anxiety

affects health care expenditures in pulmonary or cardiac patients. The hypothesis is that

mental health treatment will correspond to a decrease in health care expenditures.

Research Question 3

 After controlling for demographic characteristics, comorbidities, insurance status,

and perceived mental and physical health status, do pulmonary and cardiac patients with