As we have discussed anxiety is a normal human emotion. It is also a symptomatic feature of many different psychiatric disorders. Therefore, the clinician must determine if the diagnosis of an anxiety disorder best accounts for the symptoms. The mere presence of some anxiety symptoms does not automatically indicate an anxiety disorder. For example, someone who is obsessed with food, dieting, and exercise, because of an extreme fear becoming fat, would be diagnosed with an eating disorder; not a Phobia. Similarly, most of the Addictive Disorders (alcohol and other drugs) have some anxious features associated with obtaining and using the drug. Nonetheless, when all the symptoms are considered together, a substance-use disorder might be the most accurate diagnosis. To receive an anxiety diagnosis, anxiety must be the key and primary feature.
To complicate things further, sometimes two separate disorders may be present at the same time. Thus, it is quite possible to have both an eating disorder and an anxiety disorder. The term "co-occurring disorders" (or "comorbid" disorders) is used when two or more disorders occur at the same time. In this section, we will review some of the other psychiatric disorders where anxiety is a prominent feature, as well as disorders that frequently co-occur with anxiety disorders.
Social Anxiety (Social Phobia) and Avoidant Personality Disorder
Personality disorders are a category of disorders that are distinct from many other disorders listed in the DSM. Personality disorders refer to a chronic, inflexible, and maladaptive pattern of relating to the world. This maladaptive pattern is evident in the way the person thinks, feels, and behaves and most importantly, how they relate interpersonally to other people. It is quite possible to have both a personality disorder and an anxiety disorder. For more information about personality disorders please refer to our article entitled "Understanding Personality Disorders."
The Avoidant Personality Disorder is characterized by feelings of inadequacy, being socially reserved, and extreme sensitivity to negative criticism. People with this disorder believe they are socially inept, personally unappealing, or inferior to others. They are afraid they will be embarrassed or ridiculed in social situations. These characteristics are very similar to Social Anxiety Disorder (Social Phobia). Because of the parallels between these two disorders, some research has suggested that Avoidant Personality Disorder is merely a more severe form of Social Phobia. The comorbidity between Social Phobia and Avoidant Personality Disorder has ranged from 21% to 89% (Ralevski et al., 2005). Despite this evidence, others continue to assert these are two separate and distinct disorders. Compared to people Social Phobia, people with Avoidant Personality Disorder have more difficulty forming intimate relationships, more severe social phobia, and poorer social skills. Other studies have indicated that people with both disorders (Social Phobia and Avoidant Personality Disorder) display more anxiety, depression, and impairment in functioning, when compared to people with either disorder alone (Chambless, Fydrich, & Rodebaugh, 2008; Tillfors, Furmark, Ekselius, & Fredrikson, 2004). DSM-5 (APA, 2013) acknowledges that the overlap is so great that these two disorders may represent alternative conceptualizations of the same or similar conditions. Research will continue to explore the similarities and differences between these two disorders.
Anxiety and Depression
Anxiety and depression commonly occur together with a comorbidity rate of 50% (Hubert, 2009). Depression is a psychiatric disorder characterized by significant changes in mood. People will often say, "I feel depressed" to describe a deep feeling of sadness. This everyday usage of the term "depression" must be distinguished from the clinical usage of the term. People with clinical depression have a depressed mood almost every day, for most of the day, for at least two weeks. Depressed mood can be experienced as profound feelings of sadness, but depression can also be expressed as irritability or agitation. In children, teens, and many adult men, depression is often displayed as an irritable mood. Another important symptom of clinical depression is anhedonia. Anhedonia means a lack of interest or pleasure in most activities. Additional symptoms of depression include significant weight loss or gain; insomnia or hypersomnia (i.e., too little or too much sleep); psychomotor agitation or retardation; fatigue; feelings of worthlessness or guilt; decreased ability to concentrate; and suicidal ideation (thoughts of suicide).
It may be difficult to separate anxiety from depression when both disorders co-occur. This is because the symptoms of one disorder, might disguise the symptoms of the other disorder, due to symptom overlap. Depressive disorders and anxiety disorders both include symptoms of psychomotor agitation, difficulties with concentration, changes in appetite, and sleep disturbances. However, individuals with both anxiety and depression tend to have more severe and chronic depressive and anxious symptoms when compared to individuals with either disorder alone. Unfortunately, this increased severity of symptoms predicts a poorer response to treatment, and a larger negative impact on the quality of life (Huppert, 2009). Anxiety and depression are suspected of sharing a genetic pathway.
Anxiety and Schizophrenia
Schizophrenia Spectrum Disorders (SSDs) are disorders characterized by perceptual and cognitive difficulties (e.g., hallucinations and delusions). These disorders result in an impaired ability to distinguish between what is real, and what is not (called impaired reality testing). There is a comorbid association between SSDs and anxiety disorders. In fact, comorbid anxiety disorders and SSDs are rather commonplace, with an average comorbidity estimated at 50% (Pokos & Castle, 2006). However, the effect of having both an anxiety disorder and SSD is uncertain. Some studies suggest that having both disorders has no significant effect. Other research points to poorer outcomes when both disorders are present (Pokos & Castle, 2006).