Psychiatric comorbidity in cardiovascular inpatients: costs, net gain, and length of hospitalization.

OBJECTIVE: Although psychiatric comorbidity often goes undetected and untreated in cardiovascular patients, it is not clear whether the costs for a special treatment of psychiatric comorbidity are appropriately reflected in the reimbursement system. To investigate the economic impact of psychiatric comorbidity, we compared costs, returns, net gain, and duration of hospitalization in cardiovascular inpatients with and without psychiatric comorbidity.
METHODS: For a period of 2 years, we analyzed costs, net gain, and other outcome variables according to the diagnosis-related group (DRG) system for cardiovascular inpatients of a German university department (n = 940). Psychiatric disorders were diagnosed by the treating physicians based on clinical criteria and results from the Patient Health Questionnaire (PHQ). With respect to the outcome variables, we compared patients with and without a psychiatric disorder, controlling for sociodemographic characteristics.
RESULTS: The average total costs of hospitalization (mean ± S.E.) for cardiovascular patients without psychiatric comorbidity and for patients with psychiatric comorbidity differed significantly (€5142 ± 210 vs. €7663 ± 571; d = 0.39). The increased costs for patients with psychiatric comorbidity were related to elevated returns, but the net gain for patients without psychiatric comorbidity was €277 ± 119. In contrast, the treatment of internal medicine patients with psychiatric disorders resulted in a net loss of -€624 ± 324 (overall group difference, d = -0.25).
CONCLUSION: Psychiatric comorbidity in cardiovascular inpatients leads to higher costs that are not reflected in the current reimbursement system in Germany. The inappropriate reimbursement of psychiatric comorbidity in cardiovascular inpatients may result in a serious undertreatment of these patients.