conditions, pulmonary conditions, and psychological conditions have been identified as

expensive chronic conditions in the US health care system, when cardiac conditions and

pulmonary conditions are comorbid with psychological conditions, expenditures tend to

be greater than the cost of each condition alone. Primary care patients with psychological

conditions tend to utilize the health care system more often than patients without

comorbid psychological conditions. In studies of primary care patients, medical costs of

patients with depressive symptoms or major depression were higher than patients without

depression (Katon, 2003). For example, patients with congestive heart failure who also

present with depression have medical costs 26 to 29 percent higher than those with

congestive heart failure only.

 The prevalence of psychological conditions comorbid with cardiac conditions or

pulmonary conditions is high. In particular, depression and anxiety are more frequent in

these medical populations. A study determining the associations between anxiety

disorders and physical illness found that both males and females with an anxiety disorder

have higher rates of cardiac disorders and pulmonary illnesses compared to individuals

without anxiety disorders (Harter, Conway, & Merikangas, 2003). In a pilot study on

individuals with congenital heart disease, 27.3 percent met the Diagnostic and Statistical

Manual of Mental Disorders, Fourth Edition (DSM-IV) diagnostic criteria for depressive

episode and 9.1 percent met the DSM-IV criteria for generalized anxiety disorder (GAD)

(Bromberg et al., 2003). Depression comorbid with the respiratory condition, chronic

obstructive pulmonary disorder (COPD) is estimated to be up to four times more frequent

than in COPD alone (van Ede et al., 1999, as cited in Kunik et al., 2005). In a study