Comorbidity

Comorbidities are conditions that exist at the same time as the primary condition in the same patient (e.g., hypertension is a comorbidity of many conditions such as diabetes, ischemic heart disease, and end-stage renal disease). In medicine, comorbidity describes the effect of all other diseases an individual patient might have other than the primary disease of interest. Many tests attempt to standardize the "weight" or value of comorbid conditions, whether they are secondary or tertiary illnesses. A substantial proportion of these illnesses were judged to be either causing or exacerbating the patient's mental illness. A study by Koranyi of psychiatric clinic patients revealed remarkably similar findings: 43% of patients had physical illnesses and, of these, 46% had not been diagnosed by the referring doctor (non-psychiatrist physicians had missed 33%; psychiatrists had missed 50%). However, most studies have been focused on one health care service, mainly hospital care, or limited their analyses to one additional comorbid disease. In addition, previous studies on multidisciplinary health care utilization were based on self-reported questionnaires instead of health care registration data. We elaborated on these studies by taking into account a broad spectrum of comorbidities and focusing on multiple health care services by linking data of different health care registrations. Each test attempts to consolidate each individual comorbid condition into a single, predictive variable that measures mortality or other outcomes. Researchers have "validated" such tests because of their predictive value, but no one test is as yet recognized as a standard