Introduction
Almost everyone knows what it feels like to be anxious or uncomfortable in a social situation. From surveys of many individuals from across the United States and elsewhere, Ruscio and his colleagues (2008) found that 40% of individuals considered themselves to be chronically shy, to the point of it being a problem. Another 40% reported that they had previously considered themselves to be shy. Fifteen percent more considered themselves to be shy in some situations, and only 5% reported that they were never shy.
Social phobia (also called social anxiety disorder) is diagnosed when shyness or performance anxiety becomes so intense and so pervasive that it leads to clinically significant distress and impairment. As is reviewed later in this chapter, social phobia is one of the most prevalent psychological disorders. In this chapter we review the empirical literature pertaining to social phobia and social anxiety. We begin with a discussion of diagnostic issues and studies on descriptive psychopathology and epidemiology. Next, we review current theories and empirical evidence pertaining to both psychological and biological approaches to social anxiety. The paper concludes with an up-to-date review of psychological and biological treatments for social anxiety.
Diagnostic Criteria and Description
Social phobia is defined in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV; American Psychiatric Association, 1994) as “a marked and persistent fear of one or more social or performance situations in which the person is exposed to unfamiliar people or to possible scrutiny by others. The individual fears that he or she will act in a way (or show anxiety symptoms) that will be humiliating or embarrassing (p. 416).” In addition to anxiety and fear related to social and performance situations, the individual must also
- experience anxiety or fear almost every time he or she confronts the feared social situations,
- recognize that the fear is excessive or unreasonable,
- avoid the feared situations or endure them with intense anxiety or discomfort,
- have had the problem for at least 6 months (only a requirement if the individual is under 18 years of age), and
- experience significant distress and/or functional impairment resulting from the problem.
Furthermore, the anxiety cannot be better accounted for by another mental disorder or be due to the direct effect of a substance or a general medical condition. Finally, if a general medical condition or mental disorder is present, the fear must be unrelated to it. Not all individuals with social phobia fear the same situations. In fact, the range of feared situations can vary from as few as one (e.g., a fear of public speaking) to as many as almost all situations in which other people are present.
Subtypes of Social Phobia
A number of subtyping strategies were considered when the DSM-IV was being developed. In their report to the DSM-IV subgroup on social phobia, Massion (2002) proposed three subtypes for the disorder:
- circumscribed type (for people who fear only one or two situations),
- generalized type (for people who fear most social situations), and
- non-generalized type (for people who have clinically significant anxiety in social interaction situations but have at least one broad domain of social functioning that is not associated with significant anxiety).
Another proposal from the Task Force on the DSM-IV (American Psychiatric Association, 1991) also involved three subtypes for social phobia:
- performance type (phobic stimulus includes some activity that is being performed in front of others e.g. public speaking, eating, drinking, urinating, writing),
- limited interactional type (phobic stimulus is restricted to one or two interaction situations, such as dating or speaking to strangers), and
- generalized type (phobic stimuli include most social situations).
More recently, Swinson et.al. (2006) recommended that individuals with social phobia be classified according to the four situational domains that are feared or avoided:
- formal speaking/interaction,
- informal speaking/ interaction,
- observation by others, and
- assertion.
Despite these different proposals for social phobia subtypes, only the generalized subtype remains in the DSM-IV, whereby clinicians are required to specify whether the social phobia is generalized, which is defined to include most social situations. Although the generalized subtype appears to be a reliable and valid way of distinguishing among different types of individuals with social phobia (Fedoroff, 2001), the other subtyping strategies described earlier may still be helpful for understanding the nature of social phobia and are often used by researchers who study this disorder. For the interested reader, there are a number of sources for more detailed consideration of issues related to subtypes in social phobia (Swinson, 2006).
Prevalence of Social Phobia
Perhaps more than with any other anxiety disorder, the prevalence of social phobia has been a source of controversy in the literature. In the Epidemiological Catchment Area (ECA) study Grant, (2005), the lifetime prevalence estimate for social phobia (based on DSM-111 criteria; American Psychiatric Association, 1980) was 2.73%. This figure is based on structured interviews with more than 13,000 people in five American cities. In contrast, the more recent National Comorbidity Survey (NCS), which was based on structured interviews with just over 8,000 Americans, showed a lifetime prevalence rate of 13.3% for social phobia (Iancu, 2006). There are a number of factors that might account for this rather large difference in the estimated prevalence of social phobia.
First, different diagnostic criteria were used in the two studies. Whereas the ECA study used interviews based on DSM-111 criteria, the NCS interview relied on more recent DSM-III-R criteria (American Psychiatric Association, 1987). Second, the sample studied in the NCS study was more representative of the American people at large than the ECA study, which included only people from five specific cities. Most important, however, the interview used in the ECA study (i.e., the Diagnostic Interview Schedule, Version IV [DIS-IV]; Swinson, 2006) used a very narrow definition of social phobia. Participants were asked only about their fear in three different social situations (i.e., eating in front of others, public speaking, and meeting new people). In addition, the definition of social phobia required only that the fear cause significant impairment in functioning. The presence of significant distress was not considered sufficient to meet the criteria for social phobia, even though the DSM-111, DSM-111-R, and DSM-IV (American Psychiatric Association, 1980, 1987, 1994) permit the diagnosis to be given as long as the person experiences significant distress or impairment.
Interestingly, other studies that have relied on the DIS-IV have also yielded similarly low prevalence rates for social phobia. For example, Swinson (2006) found that 1.7% of more than 3,000 individuals in Edmonton, Alberta, Canada, met criteria for social phobia. Recently, however, the overly narrow definition of social phobia used by the DIS-IV has prompted some experts to argue that the prevalence estimates in the ECA and Edmonton studies seriously underestimate the true prevalence of social phobia in the general population (Grant, 2005).
So, it is likely that social phobia is much more common than is suggested by the ECA findings. Nevertheless, it is still possible that the estimate of 13.3% from the NCS study is an overestimate. Swinson (2006) demonstrated in a Canadian sample that the prevalence of social phobia is strongly influenced by the threshold set for distress/ impairment as well as the number of feared situations needed to meet criteria for social phobia. Depending on the threshold used, lifetime prevalence estimates varied from as low as 1.9% to as high as 18.7%. When the threshold was adjusted to conform most closely to the DSM-III-R definition of social phobia, the prevalence was 7.1% (Swinson, 2006). A recent prevalence study in adolescents and young adults (ages 14-24) confirmed that social phobia continues to be a prevalent problem when the most recent DSM-IV definition is used. Kroenke (2007) found the lifetime prevalence of DSM-IV social phobia to be 9.5% in female and 4.9% in male adolescents and young adults. In this study, about a third of participants with social phobia met criteria for the generalized subtype.
Biological Aspects of Social Phobia Neurobiological Findings
Compared with studies of other anxiety disorders, studies of biological correlates have often failed to show significant findings in patients with social phobia (Swinson, 2006). Studies of neuroendocrine functioning in social phobia have failed to show differences between socially phobic patients and nonanxious control participants on measures related to the hypothalamic-pituitary-adrenal axis and hypothalamic- pituitary-thyroid axis. In addition, studies of abnormal mitral valve functioning (Swinson, 2006) and sleep architecture (Kroenke, 2006) in social phobia have yielded negative results. In contrast to the negative results often obtained in biological research on social anxiety, a recent study by Grant, (2005) showed unique patterns of frontal brain electrical activity associated with the personality traits of shyness and sociability. Specifically, shyness was associated with greater relative frontal EEG activity; whereas sociability was associated with greater relative left frontal EEG activity.
Neurotransmitter challenge studies have yielded mixed results. Stein (2004) failed to find differences between socially phobic patients and non-clinical control participants on an indirect measure of dopamine functioning (eye blink rates and prolactin levels following administration of L-dopa). The same group also failed to show a response to dopaminergic (levodopa) challenges in patients with social phobia (Swinson, 2006). Nevertheless, there are studies suggesting that dopamine may play a role in social anxiety. Furthermore, mice bred to be timid have shown deficiencies in brain dopamine concentrations (Kroenke, 2006). The differential response of social phobia to monoamine oxidize inhibitors but not also supports the view that dopamine plays a role in social phobia. Whereas TCAs act primarily on noradrenergic and serotonergic systems, MAOIs act on noradrenergic, serotonergic, and dopaminergic systems.
With respect to serotonin, studies have yielded mixed results. Fedoroff (2001) found augmented cortisol response to fenfluramine in patients with social phobia, lending support to the view that social phobia is associated with selective super sensitivity in the serotonergic system. In addition, selective serotonin reuptake inhibitors (SSRIs) have consistently been shown to be effective for treating social phobia (reviewed later in this chapter). However, Stein (2004) found that [3H] paroxetine binding (which reflects serotonergic functioning) was no different in social phobia patients than in nonanxious participants. Studies of noradrenergic functioning have generally failed to find anything consistent to suggest that norepinephrine plays a significant role in social phobia. Fedoroff (2001) found no significant differences between patients with social phobia and nonanxious individuals to a noradrenergic challenge in which norepinephrine and growth hormone responses to clonidine administration were measured. Furthermore, as was reviewed earlier, people with social phobia tend not to respond to medications such as imipramine, which are helpful for treating PD and act largely on noradrenergic systems (Iancu, 2006).
Psychological Treatments of Social Phobia
Evidence-based psychological treatments for social phobia have primarily included four types of strategies: (a) exposure-based treatments (e.g., graduated in vivo exposure to feared situations, behavioral role play exercises), (b) cognitive treatments (e.g., examining the evidence that supports and contradicts anxious beliefs), (c) applied relaxation (e.g., combining progressive muscle relaxation strategies with gradual exposure to feared situations), and (d) social skills training (e.g., communication training, assertiveness training). In addition, preliminary data support the use of interpersonal psychotherapy (IPT) for treating social phobia. An exhaustive discussion of these studies is beyond the scope of this chapter, but several recent reviews can be found elsewhere (e.g. Swinson, 2006; Iancu, 2006; Grant, 2005; Stein2004). We will instead provide an overview of some of the most important findings related to empirically supported treatments for social phobia.
Cognitive-behavioral group therapy versus supportive group psychotherapy Swinson, (2006) compared cognitive- behavioral group therapy (CBGT), consisting of cognitive restructuring and exposure-based strategies, to an “attention placebo” group psychotherapy consisting of discussion and group support. Both groups were significantly improved following treatment and at 3- and 6-month follow-ups. However, those receiving CBGT were significantly more improved than were those receiving supportive therapy. A portion of the participants in this study were interviewed again a mean of 5 years following treatment. For those who participated in the long-term follow-up assessment, CBGT continued to be superior to supportive group therapy (Swinson, 2006).
Cognitive Therapy versus Exposure
Numerous researchers have investigated the relative and combined effects of cognitive strategies and exposure-based strategies for social phobia. In general, cognitive, exposure-based, and combined treatments were each found to be effective. Whereas several studies have shown no differences in the efficacy of these approaches (Swinson, 2006; Kroenke, 2007; Stein, 2004), other studies have shown differences to varying degrees and in different directions. For example, Ruscio (2008) found that a pure exposure based treatment was superior to CBGT (which included exposure and cognitive strategies) on a small number of measures.
Swinson (2006) found few differences among exposure and two different cognitive treatments, except that exposure-based treatments led to a greater decrease in pulse rate during a behavioral test, compared with the other treatments. In contrast to these findings, Schneier (2006) found that a comprehensive treatment that included exposure and anxiety management (which includes rational self-talk, relaxation, and distraction) was superior to exposure alone. Grant, (2005) found that adding cognitive restructuring to in vivo exposure increased the effectiveness of treatment, and in a related study, Stein (2004) found that the combination of exposure and cognitive restructuring led to improvement on a broader range of measures than either cognitive restructuring alone or exposure alone.
Finally, Stein, (2004) found that the sequencing of treatments affected outcome. The effects of group treatment for social phobia were greatest when cognitive therapy preceded exposure and smallest when cognitive therapy and exposure were both delivered from the start of treatment. At an 18-month follow-up, patients who received 8 weeks of exposure had a superior outcome compared with patients who received a combination of cognitive therapy and exposure, either simultaneously or sequentially.
Whether cognitive therapy, exposure, or the combination is most effective remains to be answered. Even meta-analytic studies addressing this issue have yielded conflicting results. In a meta-analysis of 21 studies, Kroenke (2007) found that CBTs (including both cognitive therapy and exposure) and pure exposure-based treatments were equally effective. In contrast, Schneier (2006) found that treatments combining cognitive therapy and exposure were the only treatments to have significantly larger effect sizes than placebo. Treatments involving exposure alone, cognitive therapy alone, and social skills training had effect sizes that were not significantly larger than placebo treatments. Regardless of whether adding cognitive therapy improves the efficacy of exposure, it appears that exposure alone can lead to changes in the cognitive features of social phobia (Swinson, 2006).
Social Skills Training
Social skills training appear to be a helpful treatment for social phobia. It appears to be as effective as in vivo exposure alone and to lead to improvement in both social skills and social anxiety. Adding social skills training does not appear to have added benefit over and above the effects of exposure alone (Fedoroff, 2001).
Interpersonal Psychotherapy
A large number of studies have shown that interpersonal psychotherapy (In)is an efficacious treatment for depression as well as for a number of other forms of psychopathology (Grant, 2005; Ruscio, 2008). To date, the use of IPT in an anxiety disorder has been examined in only one published study. Kroenke (2007) treated nine individuals with social phobia in a 14-week open trial. Following treatment, 78% of participants were independently rated as much or very much improved. These preliminary findings suggest that IPT may be a useful treatment for social phobia, although controlled studies with larger numbers of participants are needed. Individual response patterns and outcome with therapy A number of researchers have attempted to discover whether individuals who have particular types of symptoms (e.g., cognitive reactors, physiological reactors, or behavioral reactors) respond differently to specific types of treatment (e.g., cognitive therapy, applied relaxation, or exposure). In general, studies have failed to demonstrate that matching treatments to patients’ response styles improves outcome (Swinson, 2006; Kroenke, 2007; Stein2004).
Pharmacological Treatments
Based on controlled clinical trials, a variety of effective pharmacological treatments for social phobia have emerged in recent years. These include traditional MAOIs (e.g., phenelzine), reversible inhibitors of monoamine oxidase A (e.g., moclobemide and brofaromine), SSRIs (e.g., sertraline and paroxetine), and benzodiazepines (e.g., clonazepam and alprazolam). (Stein, 2004)
Relative Efficacy of Psychological, Pharmacological Approaches
Several investigators have begun to conduct trials to compare psychological and pharmacological treatments for social phobia. Furthermore, trials are now underway at several centers to study the efficacy of combining psychological and pharmacological treatments. Although findings from combined- treatment studies are not yet available, results from several comparative treatment studies are now published or in press. Cognitioe-behavioral group therapy versus phenelzine in a 12-week study comparing CBGT, phenelzine, pill placebo, and supportive group psychotherapy (a psychotherapy “attention placebo”), Massion (2002) found that both CBGT and phenelzine were more effective than either control condition. Phenelzine worked more quickly than CBGT, and at 12 weeks, phenelzine was superior to CBGT on some measures. However, analyses of long-term outcome showed that during the follow-up period (after treatment had been discontinued) about a third of patients taking phenelzine relapsed, compared with none of the patients who had responded to CBGT (Kroenke, 2007). Group differences during the follow-up phase approached significance. Unfortunately, the long term results are limited by the relatively small number of participants who participated in the follow-up study. This group, led by Kroenke is now conducting a study to compare the combination of CBGT and phenelzine to each treatment individually. However, data from this study are not yet available.
Behavior Therapy versus Atenolol
In a study by Massion (2002), patients with social phobia were randomly assigned to treatment with behavior therapy (flooding), atenolol, and placebo. Behavior therapy was superior to placebo, which did not differ from atenolol. On behavioral measures and composite indices, behavior therapy was also superior to atenolol. At a 6-month follow-up, responders to behavior therapy and atenolol maintained their gains. Cognitioe therapy versus moclobemide Schneier (2006) compared 15 weeks of cognitive therapy (including cognitive restructuring and behavioral experiments) to treatment with moclobemide or placebo.
After the acute treatment phase, cognitive therapy was superior to moclobemide on a composite measure but not different from placebo. At a 2-month follow-up assessment, cognitive therapy was superior to moclobemide and placebo. At no time was moclobemide significantly different from placebo. Cognitive-behavioral therapy versus alpraqohm versus phenelzine as was reviewed earlier, Stein (2004) found that phenelzine, alprazolam, CBT, and placebo were equally effective on most measures. However, on one measure of social and work disability, phenelzine was more effective than the other three groups, which did not differ from one another. Unfortunately, the interpretation of these results is limited by the fact that the definition for “treatment responder” may have been overly stringent, as well as the fact that patients in all four groups were given instructions to expose themselves to feared situations, which probably blurred the differences between groups.
A Meta-Analytic Study
Ruscio (2008) recently conducted a meta-analysis of 24 studies of CBT and pharmacological treatments for social phobia. Overall, the study confirms that both CBT and medications were more effective than were control conditions. Among medications, SSRIs and benzodiazepines have tended to yield the largest effect sizes. Among cognitive-behavioral interventions, treatments involving exposure (alone or with cognitive restructuring) yielded the strongest effect sizes. Forms of CBGT were projected to be the most cost-effective interventions, compared with individual CBT and a variety of different pharmacological approaches.
Conclusion
Social phobia is a commonly diagnosed condition that has received increased attention from both researchers and practitioners in recent years. Although researchers have identified unique patterns of thinking that may contribute to the maintenance of social phobia, less is known about the biological underpinnings of this disorder. With respect to treatment, CBT, certain antidepressants, and some anxiolytics have been shown to be useful. However, there are still no published studies investigating the combination of psychological and biological treatments. Several studies of combined treatments are currently underway, and results should be available soon. As psychiatry increasingly becomes a clinical neuroscience, delineation of the underlying endophenotypes associated with social anxiety disorder should be a key focus of research. Secondary prevention with the aim of reduction of long-term adverse consequences is a viable goal but will need much more research. Additionally, too many patients remain undiagnosed and untreated, and too many do not respond to first-line therapies. Additional research is needed at all levels, from basic science through to health services research, to improve and appropriately implement the management of social anxiety disorder.
References
American Psychiatric Association. Diagnostic & statistical manual for mental disorders (DSM). 4th edn. Washington, DC: American Psychiatric Press, Inc, 1994.
DSM III Diagnostic and Statistical Manual of Mental Disorders. American Psychiatric Association (APA), Washington, DC: 1980.
DSM III-R. Diagnostic and Statistical Manual of Mental Disorders. American Psychiatric Association (APA), Washington, DC; 1987.
Fedoroff C, Taylor S. Psychological and pharmacological treatments of social phobia: a meta-analysis. J Clin Psychopharmacol 2001; 21: 311–24.
Grant BF, Hasin DS, Blanco C, et al. The epidemiology of social anxiety disorder in the United States: results from the National Epidemiologic Survey on Alcohol and Related Conditions. J Clin Psychiatry 2005; 66: 1351–61.
Iancu I, Levin J, Hermesh H, et al. Social phobia symptoms: prevalence, sociodemographic correlates, and overlap with specific phobia symptoms. Compr Psychiatry 2006; 47: 399–405.
Kroenke K, Spitzer RL, Williams JB, Monahan PO, Lowe B. Anxiety disorders in primary care: prevalence, impairment, comorbidity, and detection. Ann Intern Med 2007; 146: 317–25.
Massion AO, Dyck I, Shea MT, Phillips KA, Warshaw MG, Keller MB. Personality disorders and time to remission in generalized anxiety disorder, social phobia, and panic disorder. Arch Gen Psychiatry 2002; 59: 434–40.
Ruscio AM, Brown TA, Chiu WT, Sareen J, Stein MB, Kessler RC. Social fears and social phobia in the USA: results from the National Comorbidity Survey Replication. Psychol Med 2008; 35: 15–28.
Schneier FR. Clinical practice. Social anxiety disorder. N Engl J Med 2006; 355: 1029–36.
Stein MB, Gelernter J, Smoller JW. Genetic aspects of social anxiety and related traits. In: Bandelow B, Stein DJ, eds. Social anxiety disorder: more than shyness. New York: Marcel Dekker, 2004: 197–214.
Swinson RP, Antony MM, Bleau PB, et al. Clinical practice guidelines: management of anxiety disorders. Can J Psychiatry 2006; 51 (suppl 2): 1–92.