Studies and Facts on Comorbidity

Different minds.
Comorbidity means having more than one diagnosis. Getty / DrAfter123

In simple terms, comorbidity refers to the presence of more than one disorder in the same person. For example, if a person is diagnosed with both social anxiety disorder (SAD) and major depressive disorder (MDD), they are said to have comorbid (meaning co-existing) anxiety and depressive disorders.

The term comorbidity was coined in the 1970s by A.R. Feinstein, a renowned American doctor, and epidemiologist. Feinstein demonstrated comorbidity through the example of how people who suffered from rheumatic fever, also usually suffered from multiple other diseases.

Comorbidity Is Not Uncommon

It's not uncommon for people to suffer from two disorders or illnesses at once. In fact, health care professionals say the amount of people suffering from multiple diseases is increasing each year.  About 80 percent of Medicare spending in the United States is devoted to people suffering from four or more chronic medical or psychological conditions. 

In fact, more than 68 percent of adults with social anxiety disorder also have at least one other medical condition.

Comorbidity can include a situation where a person receives a medical diagnosis that is followed by social anxiety disorder, or it can be one disorder that is followed by another disorder.


In the U.S. National Comorbidity Survey, 51 percent of patients with a diagnosis of major depression also had at least one anxiety disorder and only 26 percent of them had no other mental disorder. However, in the Early Developmental Stages of Psychopathology Study, 48.6 percent of patients with a  diagnosis of major depression also had at least one anxiety disorder and 34.8 percent of them had no other mental disorder.

Many studies have concluded that comorbidity is more common now than in the past. This can be due, in part, to better screening for social disorders. The medical field has focused much of its attention on the co-occurrence of mood and anxiety disorders, as well as psychosis and substance use disorders.

Psychiatric Comorbidity

Comorbid in medical terms relates to a person suffering two different medical conditions or disorders at the same time. However, in the psychiatric community, comorbid can refer to a person who suffers from multiple symptoms whereby a psychiatrist cannot come up with a single psychiatric diagnosis.

With each revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM), psychiatric comorbidity has become more common in the general population. Some in the medical world say this is because DSM-V includes enhanced descriptions that divide psychiatric behaviors and symptoms into very different, yet distinct diagnoses.

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View Article Sources
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