Avoidant Personality Disorder (APD)
The diagnostic criteria for avoidant personality disorder overlap significantly with those of SAD. In other words, the symptoms of the two disorders are mostly the same. Because of that, there has been a debate about the sense of distinguishing between the two disorders. Individuals suffering from generalized social anxiety (anxiety in most social situations) display the highest rates of additional APD (Alden, Laposa, Taylor, & Ryder, 2003). In addition, people suffering from these two conditions experience higher symptom severity as well as social skills deficits (Bögels et al., 2010; Chambless, Fydrich, & Rodebaugh, 2008). Given these data, it has been suggested that avoidant personality disorder is a more severe version of social anxiety disorder (Spokas & Cardaciotto, 2014). However, before this hypothesis can be accepted, more research is necessary.
People diagnosed with generalized social anxiety disorder have a 44-69% chance of suffering from additional APD, as compared to roughly 2% for people who only fear one social situation (Brown, Heimberg, & Juster, 1995; Tillfors, Furmark, Ekselius, & Fredrikson, 2004). Compared to SAD sufferers without APD, socially anxious people who also suffer from avoidant personality disorder were found to display a higher likelihood of earning lower wages, being unmarried, and meeting the criteria for an additional mood disorder (Brown et al., 1995). This group of individuals has also been found to engage in more avoidance behavior as long as they are not certain of being liked and approved of. They also tend to experience a stronger fear of being embarrassed due to anxiety symptoms that might be visible to others.
Whether or not a socially anxious person additionally suffers from APD does not seem to have any negative effect on treatment effectiveness (Szafranski, Talkovsky, Farris, & Norton, 2014). Two different research teams confirmed this proposition in their studies (Van Velzen, Emmelkamp, & Scholing, 1997; Brown et al., 1995). So, apart from greater symptom severity and functional impairment, an additional diagnoses of APD does not seem to have a significant weight. The differences between the two disorders are due to quantitative traits, not qualitative ones (Szafranski, Talkovsky, Farris, & Norton, 2014). Others have argued that while SAD is mostly related to phobic factors, APD has its focus on the person’s interpersonal abilities and engagement (Kose et al., 2009).
Conduct Disorder (CD) & Antisocial Personality Disorder (ASPD)
When thinking of a socially anxious person, most people imagine a timid, reserved individual who tries to comply with social norms and expectations as best as possible. Conduct Disorder is characterized by a difficulty to follow rules, trouble showing empathy, and engagement in other antisocial behaviors. In simple terms, antisocial personality disorder often develops out of CD. The two disorders describe pretty much the same symptoms, with CD being the diagnosis of choice for children and adolescents, and ASPD for adults. Affected people may lie a lot, manipulate and disrespect others, display feelings of grandiosity, and are at high risk of getting in trouble with the law.
Despite these huge differences in symptoms, there is a small subgroup of people with ASPD that shows an elevated risk of being diagnosed with SAD at some point in their lives (Goodwin, Hamilton, 2003). While women are usually more prone to developing anxiety disorders, about 75% of this specific group are men (Coid & Ullrich, 2010). Furthermore, it has been found that males with nongeneralized SAD are more likely to also suffer from conduct disorder, but not females (Marmorstein, 2006). Among these men, a combined diagnosis of the two disorders is more likely for younger individuals (Coid & Ullrich, 2010).
It has been suggested that the link between the two disorders is the anxiety which motivates the person to engage in antisocial behavior (McMurran, 2011). Therefore, the anxiety may represent a crucial factor for the development and maintenance of CD and ASPD (Bubier & Drabick, 2009). It has been pointed out however, that it is not clear whether the anxiety develops first and precedes the aggression. Treatment should aim for the development of better skills when dealing with threats, as well as disengaging the individual from his or her hypervigilant state, and improving overall social confidence (McMurran, 2011).