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Article in Current Psychiatry Reports · March 2016

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Avoidant Personality Disorder: A Current Review

Anna Weinbrecht, Lars Schulze, Johanna Boettcher, Babette Renneberg Clinical Psychology and Psychotherapy, Freie Universität Berlin, Berlin, Germany

Running Title:                        Avoidant personality disorder: a current review

Corresponding author:          Anna Weinbrecht, M.Sc.

Clinical Psychology and Psychotherapy Freie Universität Berlin Habelschwerdter Allee 45

14195 Berlin

e-mail: weinbrecht@zedat.fu-berlin.de phone: ++49 30 838 55743

fax:      ++49 30 838 54945

 

Abstract 

This review focuses on recent research on diagnostic aspects, etiology, and treatment of avoidant personality disorder (AVPD). Current studies stress the close relation between AVPD and social anxiety disorder, the influence of genetic factors in the development of AVPD and the relative stability of symptoms. Treatment approaches should target the pervasive patterns of social inhibition, feelings of inadequacy, and hypersensitivity to negative evaluation. Empirical evidence for cognitive-behavior, and schema therapy is promising. Few other therapeutic approaches have been developed, but until now, these have only been investigated in case studies. We conclude that AVPD qualifies as a neglected disorder and that more research specifically on avoidant personality disorder symptoms and its treatment is needed.

 

Introduction

Hallmark characteristics of avoidant personality disorder (AVPD) are a pervasive pattern of social inhibition, feelings of inadequacy, and a hypersensitivity to negative evaluation.

Accordingly, persons with AVPD show a marked avoidance of social interactions, while perceiving themselves as unwanted and isolated from others. These symptoms are associated with pronounced impairments in daily life and major societal costs [1, 2]. For instance, recent findings highlighted considerable impairments in mental (e.g., low self-efficacy, mental distress), social (e.g., lower level of education, lower income, not in paid work), and somatic (e.g., presence of somatic diseases) aspects of individuals with AVPD [3]. Even in comparison to other personality disorders (PD), AVPD was associated with the highest level of impairment in daily functioning [4, 5].

AVPD is not only among the most impairing PDs but also one of the most prevalent PD. The median lifetime prevalence is estimated to be 1.7% in community samples and the estimate of AVPD as a comorbid disorder is about 14.7% in psychiatric outpatients [6, 7]. Despite the high prevalence and debilitating nature, AVPD is relatively understudied. Most of the available research focuses on diagnostic aspects, whereas effects of pharmacological treatments are largely unknown and research on psychotherapeutic interventions is scarce.

The present review aims to summarize the current state of research in AVPD. In particular, we will focus on recent findings on (1) diagnostic aspects, such as comorbidity and stability of symptoms, (2) etiology, and (3) treatment approaches for AVPD.

 

Diagnostic Aspects

While the publication of the DSM-5 did not result in changes for the diagnostic classification of AVPD, section III of the DSM-5 includes an alternative proposal for the classification of PDs [8]. This dimensional classification approach characterizes PDs by two essential features: A. impairments in personality functioning and B. the presence of pathological personality traits. The system includes six specific PD diagnoses, one of which is AVPD. With regard to impairments in personality functioning in AVPD, the alternative approach suggests characteristic difficulties in the following areas: identity, self-direction, empathy, and intimacy. In addition, this account proposes anxiousness, withdrawal, anhedonia, and intimacy avoidance to be pathological personality traits in individuals with AVPD.

In the following sections, we will discuss the relationships between AVPD and other mental disorders or personality traits as well as the stability of AVPD symptoms.

 

 

Relationship to Social Anxiety Disorder

Social anxiety disorder (SAD) is the most common comorbid diagnosis of AVPD. In a large national epidemiological study co-occurrence of generalized social phobia in individuals with AVPD was estimated to be 40% [9], whereas other studies report rates of comorbidity of up to 88% [10] and 100 % [11]. A meta-analysis concluded that AVPD is additionally diagnosed in 46% of individuals with SAD [12]. As a result, numerous articles focus on the delineation of AVPD and SAD. Many studies support the continuum hypothesis of severity: both disorders capture clinical representations of social anxiety, however patients with AVPD demonstrate more severe symptoms and impairments than patients with SAD [for reviews, see 13, 14, 15]

In particular, these studies illustrate that differences in impairments or symptom load between both disorders are the consequence of varying degrees of social anxiety. Marques and colleagues [16] examined whether a comorbid AVPD diagnosis yields additional clinically relevant information in a sample of 326 individuals seeking treatment for generalized social phobia. They reported that individuals with a comorbid AVPD diagnosis showed higher impairments across various aspects, such as work, social, or family domains. It should be noted that the higher severity of social anxiety in individuals with a comorbid AVPD explained these differences in impairment. Eikenaes and colleagues [17] provided further evidence in favor of the continuum hypothesis. Individuals with AVPD scored lower on aspects of personality functioning like enduring relationships and self-reflexive functioning (the competence to understand the possible meanings of and causal relations between internal and external experiences) than individuals with SAD alone. Group differences in these aspects of personality functioning were explained by the presence of comorbid disorders, such as SAD.

On the other hand, there are still arguments for a qualitative difference between the disorders. Sense of inferiority and passivity are examples for possible factors specific to AVPD [for reviews, see 18, 19]. Paradoxically, support for specific factors of AVPD can also be drawn from the same studies that provided evidence for the continuum hypothesis. Marques and colleagues [16] found evidence that emotional guardedness, indicated by the AVPD criteria ‘restraint in intimate relationships’, might be a specific feature of AVPD that is not captured by the generalized social phobia diagnosis. Eikenaes and colleagues [17] showed that AVPD can be distinguished from SAD on aspects of personality functioning like self-respect, feeling recognized and intimacy.

What does this mean for the distinction between SAD und AVPD? As reflected by the diagnostic criteria, social fears seem to be more ‘ingrained’ in the self-concept of patients with AVPD and therefore interfere with more life domains and decisions compared to patients with SAD. In this line of reasoning, higher emotional guardedness, less self-respect, problems to express feelings in intimate relationships, and stronger overall avoidance can be considered as expressions or consequences of extremely high social insecurity and fears. These additional problems might thus be perceived as specific for AVPD (see Figure 1). The decision of whether both disorders are expressions of the same construct vastly depends on how widely one defines and measures social anxiety and the definition of what qualifies as a qualitative difference between AVPD and SAD. This might explain why after years of extensive research, results on the delineation of SAD and AVPD are still inconclusive.

– Insert Figure 1 about here –

  

Relationship to other PDs and Dimensions of Personality

Previous research has shown substantial overlap among categorical diagnoses of PDs [20]. Although AVPD is among the PDs that are the most likely to be diagnosed solely [7], comorbidity rates with other PDs are high. For example, Stuart and colleagues [21] reported that 59% of individuals with dependent PD also met criteria for AVPD.

Bachrach, Croon, and Bekker [22] examined the factor structure of PD symptoms in a sample recruited from a mental health institute. The authors performed a factor analysis of self- reported PD symptoms for narcissistic, avoidant, borderline and dependent PD symptomatology and identified six subscales. However, the subscales were still highly correlated. Interestingly, two factors explained the correlations among the scales: internalizing personality problems and externalizing personality problems. This is comparable to the findings of the most comprehensive longitudinal study on the structure of mental disorders by Caspi et al. [23] and indicates that the high comorbidity of AVPD with other PDs might be due to an underlying latent factor reflecting “internalizing personality problems”.

A solution to the problem of high comorbidity amongst PDs lies in the application of a dimensional classification system. Wright et al. [24] provided support for the notion that existing PDs can be conceptualized as expressions of different personality traits. The authors reanalyzed data of the Longitudinal Study of Personality Disorders [25] to examine the relationship between AVPD and basic personality traits using parallel process growth curve modeling. They demonstrated that in a non-clinical sample AVPD symptom trajectories had a significant negative relationship with the personality traits trajectories of interpersonal dominance and affiliation and a significant positive relationship to rates of change in neuroticism. Hence, they provided further evidence for a continuum between normal personality and personality pathology and replicated previous findings that neuroticism seems to play a crucial role for AVPD [13].

The classification of PDs in a dimensional system has caused lively debate in the development of the DSM-5 [20]. An alternative model of PDs, describing personalities in a hybrid categorical- dimensional approach, has been included in the research criteria of the DSM-5 (see above).

 

Stability of Symptoms

Another problem in the process of conceptualizing PDs in the DSM-5 was the accumulating evidence that PD symptoms may not be as stable as previously assumed. Initial findings in AVPD provided evidence for a modest to moderate stability of AVPD symptoms [26, 25, 27, 28]. Recently, Hallquist and Lenzenweger [29] reanalyzed data of the Longitudinal Study of Personality Disorders to shed light on the stability of PDs over four years. Two groups of young adults were examined: individuals with possible PD and individuals with no PD at baseline. In the group with a possible PD at baseline, 41% of the individuals showed subclinical to clinical AVPD symptoms that remained relatively stable over time. Interestingly, one fifth of individuals without a PD at baseline developed AVPD symptoms over a four-year period. A longitudinal population-based twin study yielded further support for a moderate stability of AVPD symptoms [30]. In addition, findings from a clinical sample provided also support for moderate rank-order stability of AVPD symptoms over a ten-year period [31].

Taken together, findings suggest that symptoms of AVPD such as feelings of inadequacy, fears of negative evaluation and patterns of social inhibition characteristic for AVPD remain relatively stable over time. It is noteworthy that these symptoms can also evolve at later stages in life.

 

Etiology

The development of PDs is attributed to a variety of genetic, temperamental, and childhood factors. While findings of etiological aspects in AVPD are sparse, the available evidence also emphasizes the necessity to take genetic and personality factors into account. A population-based twin study estimated a heritability of .64 for symptoms of AVPD [32]. Based on their findings, the authors concluded that this genetic influence stabilizes in early adulthood. Environmental factors contribute to the stability and maintenance of symptoms in AVPD [30]. Further evidence for a genetic component in the development of AVPD was provided by a multi-generational family study. In this study, Isomura et al. [33] illustrated that AVPD and SAD cluster in families due to a proposed genetic factor and that first-degree relatives of individuals with SAD are 3-4 times more likely to have a diagnosis of AVPD. In fact, both disorders were suggested to be etiologically related, possibly representing different expressions of the same vulnerability.

With regard to personality factors, available studies suggest a combination of harm avoidance, negative childhood experiences as well as childhood / adolescent anxiety disorders to be risk factors for AVPD [e.g., 34, 35]. A cross-sectional comparison of AVPD and SAD illustrated that increased reports of childhood neglect in AVPD might contribute to phenomenological differences between both disorders [36]. In this study, group differences remained stable even after controlling for temperamental factors. Interestingly, the relationship between retrospectively reported childhood experiences and symptoms of AVPD was mediated by early maladaptive schemas, such as subjugation, abandonment, and emotional inhibition [37].

 

Treatment

Empirical research on psychotherapeutic treatment of AVPD started in the late 1980s. Several treatment approaches were developed and tested. In most cases, treatment in these early studies was based on successful treatment approaches for SAD [38-40].

 

Cognitive Behavior Therapy (CBT)

Early CBT programs were predominantly delivered in a group format. Treatments included exposure exercises (graduated in vivo exposure) or systematic desensitization, behavioral rehearsal in role-plays, self-image work including video feedback, and social skills training [38- 40]. Results showed moderate to good and mostly stable improvements for individuals with AVPD. For example, Renneberg et al. [38] reported a recovery rate of 40% assessed by the Fear of Negative Evaluation Questionnaire after a four-day intensive group CBT program.

Informed by the introduction of cognitive therapy for PDs [41] and the cognitive model of social anxiety [42], subsequent studies on the treatment of AVPD included more cognitive techniques. Cognitive elements in the treatment of AVPD encompass the development of an individualized model of social fears, the identification of dysfunctional core beliefs, the development of more adaptive cognitions and beliefs, and behavioral experiments to challenge “safety behaviors” [e.g., 43, 44, 45]. In a trial comparing individual cognitive therapy to brief psychodynamic therapy for AVPD, Emmelkamp et al. [43] reported large effect sizes on self- report measures and a recovery rate of 91% on the SCID-II for the 21 patients randomized to cognitive therapy. Similarly positive results were reported by Strauss et al. [45] in an uncontrolled trial of individual cognitive therapy with N = 23 patients with AVPD. In a study comparing interpersonal to cognitive therapy for social anxiety, two thirds of the patients (28 out of 44) with comorbid AVPD no longer met diagnostic criteria for AVPD one year after treatment with no difference between treatment conditions [46]. Treatment dosage in these studies varied, ranging between 20 sessions [43] and up to 52 sessions [45].

 

Psychodynamic Treatment

Most studies examining the effectiveness of psychodynamic approaches encompass patients with any Cluster C diagnosis and do not focus solely on AVPD [47-49]. In two of these trials, outcome for AVPD was not reported separately. Barber et al. (1997) reported that 61% percent of 23 AVPD patients no longer fulfilled diagnostic criteria after 52 psychodynamic treatment sessions. Currently, Leichsenring and Salzer [50] are performing a randomized controlled trial (RCT) to test a unified protocol for the transdiagnostic psychodynamic treatment of anxiety disorders, including AVPD. The treatment of this trial is based on the supportive-expressive dynamic psychotherapy [51].

Two RCTs so far compared CBT with psychodynamic psychotherapy. Svartberg et al. found a short-term dynamic psychotherapy and CBT to be equally effective for Cluster C PDs. Emmelkamp et al. [43] compared 20 weekly sessions of CBT (based on the cognitive model of social anxiety from Clark and Wells) to brief dynamic psychotherapy and a waitlist condition. In contrast to the results of Svartberg and colleagues, the 21 AVPD individuals in the CBT condition showed significantly larger decrease in diagnostic criteria (SCID-II) and improvement on self-report measures in comparison with 23 patients treated with brief dynamic psychotherapy and the waitlist condition (N = 18). These results were maintained at 6 months follow-up.

 

Schema therapy 

Schema therapy focuses on working with schema modes, defined as momentary mind states consisting of cognitions, emotions, and behaviors, which evolved as the result of unsatisfied basic needs and corresponding developed coping styles [52]. This approach integrates cognitive- behavioral, psychodynamic, and Gestalt therapy techniques. In treating AVPD, the most relevant schema modes are the Lonely Child mode which is characterized by feelings of loneliness, unworthiness and being unloved, the Avoidant Protector mode, in which situational avoidance is activated, and the Detached Protector mode which is characterized by avoidance of inner needs, emotions and emotional contact. Furthermore, a Punitive Parent mode is active in which the feeling that oneself deserves punishment or blame is assumed to be activated [53]. In a first trial, Weertman, Arntz [54] provided preliminary evidence for the effectiveness of schema therapy elements for patients with a Cluster C diagnosis.

The same research group [55] compared individual schema therapy (50 sessions) to clarification-oriented psychotherapy and treatment as usual (TAU) for patients with a Cluster C diagnosis (N = 323 participants, N = 163 with AVPD). The authors reported a higher recovery rate for schema therapy compared to clarification-oriented and TAU for Cluster C. Over 80% of the patients treated with schema therapy recovered. Recovery was defined as not meeting criteria for any PD, assessed with the SCID-II by blinded independent interviewers. The authors did not find a significant effect of primary PD diagnosis on outcome, which indicated that 50 sessions of individual schema therapy delivered over a two-year period led to improvement in AVPD symptoms as well as on secondary outcome measures. Results were stable at three-year follow- up. Schema therapy delivered in a group setting was tested in a small pilot study with a mixed PD sample [56]. Results showed that four out of the six patients diagnosed with AVPD recovered after 20 sessions.

Taken together, schema therapy shows promising potential for treating AVPD. However, it remains unclear whether it actually provides benefit over traditional CBT. Greeven and colleagues [57] are currently conducting a RCT comparing group schema therapy to group CBT for individuals with SAD and comorbid AVPD. Planned closing date is in autumn, 2018.

Other recent approaches that showed potential for treating AVPD in single case studies include metacognitive interpersonal therapy [58], emotion-focused psychotherapy [59], acceptance and commitment therapy in combination with dialectical behavior therapy [60] as well as interpersonal psychotherapy [61]. All approaches are based on theoretical models on how AVPD symptoms develop and should best be treated. Whether one of these approaches proves superior to existing CBT, psychodynamic or schema therapy must be subject to further research.

AVPD as a Predictor of Treatment Outcome for SAD

Quite a few studies examined whether AVPD diagnosis predicts outcome for treatment of SAD [62-66]. Analyses mainly showed that individuals diagnosed with SAD and comorbid AVPD report similar change rates in social anxiety symptoms compared to individuals without a comorbid AVPD diagnosis. However, as AVPD patients start off at a higher level of severity, they also terminate treatment on a more dysfunctional level than individuals without AVPD. These results are in line with the continuum hypothesis of social anxiety as discussed above.

Despite the absence of qualitative differences, there definitely is a quantitative difference.

Patients with AVPD are more severely affected: they seem more guarded and more impaired in social life as well as in occupational issues.

 

Summary on treatment of AVPD

There are not many treatment studies that focus exclusively on patients with AVPD. Early studies demonstrated that patients with AVPD responded well to primarily behavioral techniques [38-40]. These results were followed by very few more recent trials, integrating more cognitive treatment elements [46, 43, 45]. Brief psychodynamic treatments were tested in two RCTs, with contradictory results regarding their efficacy compared to CBT [43, 49]. More recently, schema therapy showed good outcome for the treatment of AVPD [5].

 

Discussion

In 1985, Liebowitz and colleagues wrote an article on “social phobia – review of a neglected anxiety disorder”. Since then, research on SAD increased significantly and in 2015 etiology, maintenance, and treatment of SAD are well investigated. Research on AVPD, on the other hand, is still scarce. Especially in light of its high prevalence and severe associated impairments, AVPD now classifies as a neglected diagnosis in clinical research on PDs.

Recent research on the symptomatology of AVPD focused mainly on its delineation to social anxiety and other PDs. In the DSM-5 diagnostic criteria were not changed and thus the problem of high comorbidity between AVPD and other mental disorders remains. The alternative model in the supplementary material of DMS-5 provides a dimensional approach and hence addresses heterogeneity in AVPD symptomatology more adequately. Additionally, the selected pathology traits might help to develop instruments to assess specific AVPD traits. This way, the often-used SAD symptom questionnaires could be supplemented by specific AVPD questionnaires. However, although the selected pathological traits (anxiousness, withdrawal, anhedonia, intimacy avoidance) seem plausible, more research is needed to justify this selection of traits. Especially, anhedonia is a relatively new criterion.

Compared to SAD or borderline personality disorder there are only few studies on the efficacy and effectiveness of psychotherapeutic treatment for AVPD. Even though effect sizes and recovery rates for the treatment of AVPD are promising and seem comparable to the treatment of SAD, large RCTs focusing on treatment of AVPD are rare. At this point CBT and schema therapy show the strongest empirical evidence for the treatment of AVPD.

The paucity of relevant clinical trials on AVPD patients could at least partly be explained by the close relationship of SAD and AVPD. As patients with AVPD are successfully included in trials testing treatments for SAD, there may be less motivation and more problems to generate large patient groups to focus research solely on AVPD. However, in our opinion, the plain adaption of SAD protocols for the treatment of AVPD does not suffice, mainly because of the strong avoidance that these patients show. For example, cognitive therapy for SAD puts strong emphasis on experimenting with safety behaviors (e.g., like avoiding eye contact). However, patients with AVPD may be too consumed by their anxiety to be able to perform the required task (reduce safety behavior) or they might not even enter the role-play situation because of their extreme avoidance. Protocols should also include brief exercises and role-plays to build up social skills. In a study on generalized social phobia where 75% of the patients also met diagnostic criteria of AVPD, Herbert and colleagues [68] demonstrated the beneficial effect of adding social skills training to a CBT protocol.

As outlined above, treatment lengths vary greatly between different studies. Schema therapy delivered in the trial by Bamelis et al. (2014) lasted for 50 sessions spread out over more than a year. Rees and Pritchard (2015) question the necessity of prolonged treatment duration in AVPD and present the cases of two patients successfully treated in 12 sessions of cognitive therapy. However, many authors argue that it takes more time to achieve structural or emotional changes in AVPD [69, 56]. Results show no consistent trend in favor of longer or shorter treatments, and additional empirical research is needed. Furthermore, future research should target the lack on empirical research examining the relationship between number of treatment sessions and symptomatic change.

CBT and schema therapy protocols for AVPD have been developed for group and individual settings with promising results for both formats. So far, there is no evidence on which format is superior in the treatment of AVPD. A group setting yields economic advantages and offers the possibility for role-plays as well as behavioral experiments. In our research group, we have observed a steeper decline of symptoms after patients with AVPD participated in a CBT group for social anxiety. In the clinical practice, we favor accompanying single sessions to ensure that avoidance decreases and patients are well prepared for group participation. Future research has to clarify if a combination of individual single session and group therapy is most beneficial for individuals with AVPD.

 

Conclusion

In light of prevalence rates, societal costs, and the current state of research, it needs to be stated that AVPD qualifies as a neglected disorder. Up until now, the available research has primarily focused on the delineation of SAD and AVPD. Future research should shift its focus to more specific symptoms such as emotional guardedness, intimacy avoidance, or low self-respect.

These might also serve as important variables for assessing the outcome of different psychotherapeutic approaches for AVPD. With regard to the treatment of AVPD, the present review presents an urgent call for more research to identify appropriate therapeutic techniques as well as the appropriate treatment dose and setting for targeting the maladaptive schemas and elaborated avoidance patterns. Recent findings are too limited to provide a clear recommendation for the treatment of AVPD. In fact, recent attempts of the Cochrane Library to summarize beneficial and adverse effects of therapeutic interventions in AVPD failed due to difficulties to identify enough suitable studies [70, 71].

 

Conflict of Interest

The authors declare that they have no conflict of interest.

 

Benchmarks

 

• Wright, Pincus, & Lenzenweger (23) ·

In this longitudinal study, the rates of change in avoidant personality disorder symptoms were associated to rates of change in normal personality traits (interpersonal dominance, affiliation, and neuroticism). This supports the proposition that personality disorders can be conceptualized as expressions of normal personality traits and stresses the crucial role of neuroticism for avoidant personality disorder.

• Hallquist, & Lenzenweger (28) ·

In this longitudinal study, latent trajectories of personality dysfunction were investigated. Results indicated that avoidant personality disorder can develop at a later stage of life and that this is associated with lower positive emotionality.

• Gjerde, Czajkowski, Roysamb, Ystrom, Tambs, Aggen, Orstavik, Kendler, Reichborn- Kjennerud, Knudsen (29)

This longitudinal twin study provided support that genetic factors contribute more to the phenotypic stability of avoidant personality disorder than environmental factors.

• Hopwood, Morey, Donnellan, Samuel, Grilo, McGlashan, Shea, Zanarini, Gunderson, & Skodol (30) ·

This study assessed 10-year stability of personality traits and personality disorder dimensions in a clinical sample. Stability was relatively greater for traits than personality disorders.

• Bamelis, Evers, Spinhoven, & Arntz (55) ·

This study demonstrated that a greater proportion of patients with Cluster C personality disorder treated with schema therapy recovered in comparison to clarification-oriented psychotherapy and treatment as usual.

• Renner, van Goor, Huibers, Arntz, Butz, & Bernstein (68)

This pilot study determined the effects of group schema therapy in patients with personality disorder. Global distress and underlying vulnerabilities in terms of maladaptive schemas decreased from pre- to post-treatment.

 

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Figure Legends

 

Figure 1

Proposed relationship between social anxiety and additional problems, such as harm avoidance, or intimacy avoidance, in patients with avoidant personality disorder compared to social anxiety disorder or normal shyness