ComorbidityIn psychology, comorbidity refers to the presence of more than one mental disorder occuring in an individual at the same time. On the DSM Axis I, Major Depressive Disorder is a very common comorbid disorder. The Axis II personality disorders are often criticized because their comorbidity rates are excessively high, approaching 60% in some cases, indicating to critics the possibility that these categories of mental illness are too imprecisely distinguished to be usefully valid for diagnostic purposes and, thus, for deciding how treatment resources should be allocated.
Patients who are more seriously ill tend to require more hospital resources than patients who are less seriously ill, even though they are admitted to the hospital for the same reason. Recognizing this, the DRG grouper manual splits certain DRGs based on the presence of secondary diagnoses for specific complications or comorbidities (CC).