[Comorbidity of internal inpatients in the german diagnosis related groups-system]

The representation of comorbid mental disorders within the German Diagnosis Related Groups-System was investigated. First the complication and complexity level CCL of diagnoses of mental disorders (ICD-10 category F) within the G-DRG-calculation handbooks 2004 and 2005 were checked. Second the revenue based on a fictitious base rate of 3000 with the G-DRG versions 2004/2005 respectively was calculated with and without inclusion of diagnosed comorbid mental disorders of 6610 cases of both medical departments of a hospital of tertiary care level (year 2004). Only F0-diagnoses could lead to a CCL of 3. In 28.2 % of the patients at least one comorbid diagnosis of the category F of the International Classification of Diseases (mental and substance induced disorders) had been coded. Renunciation of the diagnosed mental disorders would have been resulted in a fictitious reduction in revenues based on the G-DRG version 2004 of 93 600 and on the G-DRG version 2005 of 69 000 . The Patient Clinical Complexity Level PCCL was increased 0.15 by the comorbid mental disorders in each year. To achieve an adequate representation of comorbid mental disorders in the G-DRG-system and to ensure a financial survival of psychosomatic/psychiatric CL-services coordinated efforts of psychosomatic scientific societies and hospitals taking part in the G-DRG-calculation sample are necessary.