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Research Article DEPRESSION AND ANXIETY 27:687–692 (2010) SOCIAL ANXIETY DISORDER IN ADULTS WHO STUTTER Elaine Blumgart, M.Sc., Yvonne Tran, Ph.D., and Ashley Craig, Ph.D. Background: The nature and prevalence of social anxiety disorder (social phobia (SP)) in people who stutter is uncertain, and DSM-IV differential diagnosis guidelines make it difficult to classify an adult who stutters (AWS) with SP as it is assumed any social anxiety symptoms will be a consequence of their stuttering. The aim of this study was to determine the spot prevalence of SP in AWS and to investigate differences in social anxiety between AWS and controls who do not stutter. Methods: The study involved a comprehensive assessment of 200 AWS and 200 adults who do not stutter similar in age and sex ratio. Measures included stuttering severity, health status, self-report measures of social anxiety as well as a structured diagnostic interview for SP for randomly selected sub-group of 50 from each group. Results: The AWS were found to have significantly raised trait and social anxiety, as well as significantly increased risk of SP in comparison to the controls. Findings indicated a SP spot prevalence of at least 40% in AWS, and for them to be at high risk of having Generalized SP. Conclusions: It is concluded that the DSM-IV diagnostic guidelines for diagnosing SP in AWS could result in professional confusion and have possible negative mental health ramifications. Implications for the psychological and medical treatment of AWS are discussed. Depression and Anxiety 27:687–692, 2010. r 2010 Wiley-Liss, Inc. Key words: stuttering; quality of life; social anxiety; fluency disorderl; social phobia INTRODUCTION Socialanxietydisorderorsocialphobia(SP)isadisorderin whichapersonexperiencesextremeandintenseanticipatory anxietyrelatedtobeingembarrassedinsocialinteractionsin which they believe they will be or are being scrutinized by others.[1–3] The lifetime prevalence of SP is estimated to be in the range of 7–12%,[1,3,4] with younger people (less than 60years)higheratrisk. SPnegativelyinfluencesqualityof life in domains such as vitality, mental health, and social functioning andworkproductivityhasalsobeenfoundto be significantly reduced in people with SP. The DSM-IV recognizes a generalized SP (GSP) disorder in which the person fears most social situations and a ‘‘specific’’ SP in which the person has restricted social fears. DSM-IV differential diagnosis guidelines for SP recommend the exclusion of SP in people with a condition such as stuttering that may reasonably explain the elevated social anxiety. This means that SP should only be diagnosed in adults who stutter (AWS) if they have excessive social anxiety that is independent of any fears generated by their stuttering. This differential diagnostic decision has been questioned by some who argue that the DSM-IV exclusion criteria may have unhelpful consequences,[8,9] such as the withholding of appropriate psychological and/or pharmacological treatment,[8,10] with a consequent lowered quality of life. Stein et al. attempted to address this problem by diagnosing SP inAWSiftheir social fears were out of proportion to their severity of stuttering. Published online 7 January 2010 in Wiley InterScience (www. interscience.wiley.com). DOI 10.1002/da.20657 Received for publication 16 October 2009; Revised 2 December 2009; Accepted 5 December 2009 Correspondence to: Ashley Craig, Rehabilitation Studies Unit, Northern Clinical School, Faculty of Medicine, The University of Sydney, P.O. Box 6, Ryde, NSW 1680, Australia. E-mail: firstname.lastname@example.org The authors report they have no financial relationships within the past 3 years to disclose. Rehabilitation Studies Unit, Northern Clinical School, Faculty of Medicine, The University of Sydney, Ryde, New South Wales, Australia r r 2010 Wiley-Liss, Inc. Stuttering is classified as a communication disorder (DSM-IVAxis I) with early age onset during the course of speech development. For a minority, perhaps 20%, it will persist into adulthood, with an estimated all age prevalence of around 1%. Stuttering involves involuntary disruptions to the fluency of speech, including syllable repetitions, prolongation and block- ing of sounds, and substitutions and avoidance of words. Similar to SP, many AWS experience extreme social embarrassment and fear scrutiny in a broad range of social contexts, and stuttering has been found to have a negative influence on social, emotional, and mental health, with a similar negative impact in these domains as diabetes and coronary heart disease. Iverach et al. showed that AWS had a high risk of having a co-morbid psychological disorder which was linked to less successful long-term treatment outcomes for stuttering, and stuttering has recently been found to have an elevated risk for personality disorder. Research has found that stuttering is most likely associated with elevated levels of anxiety.[14,17–19] The question of primary interest is the nature of this elevated anxiety. Preliminary research suggests that AWS have increased risk of social anxiety.[8–10,20,21] Stein et al. conducted research in a group of 16 AWS seeking treatment for their stuttering. They modified DSM-IV SP criteria to permit a diagnosis of SP when anxiety symptoms were believed to be excessive in relation to the severity of stuttering. Before they applied the criterion, 75% (n512) of their sample was diagnosed with SP using DSM-IV criteria. Applying the modified DSM criterion, they reduced this diagnosis to 44% (n57) who they believed had definite SP. Menzies et al. investigated SP in 30 AWS and concluded that 60% of their sample met DSM criteria for SP; however, they did not modify or adjust DSM criteria. Research is clearly needed to clarify how prevalent SP is in the stuttering population, and whether SP is a common Axis I co-morbidity for stuttering. No studies have investigated social anxiety in a large sample of AWS, with controlled comparisons to people who do not stutter (AWDNS). Therefore, the aim of this research was to conduct a comprehensive assess- ment of social anxiety in a large group of AWS and AWDNS and also to determine the proportion of AWS who meet DSM-IV criteria for SP. It was hypothesized that AWS would have elevated levels of social anxiety and a higher spot prevalence of SP compared to the nonstuttering controls. MATERIALS AND METHODS PARTICIPANTS The study involved a group of 200 male and female AWS and a control group of 200 AWDNS (see Table 1 for demographics). AWS were invited into the study from self-help groups (87%) as well as private speech clinics, general medical practitioners, speech pathol- ogy departments of public hospitals and community health centers (13%). No differences in age, health, or stuttering severity existed as a function of participant source. All AWS were diagnosed for their stuttering by an experienced speech pathologist. Most of the 200 AWS had sought treatment for stuttering in their lifetime (n5187; 94%), and for the 6% that had never sought treatment, reasons included treatment not available, believing they were not severe enough, and lack of faith in treatment. None had sought treatment for SP. The male to female (M:F) ratio in the study was based on epidemiological data that found the male to female AWS ratio in the community to be within the range of 2:1–4:1. The final M:F ratio in the study was 3.1:1. The adult age range for the study was 18–85 years and participants were recruited in direct proportion with the most recent Australian age distribution population statistics. Controls consisted of adult males and females recruited using the same age range used for the AWS. Although the final control group had a higher ratio of females to males than the AWS (see Table 1), this was not problematic as sex was not found to be related significantly to any variables such as anxiety. Controls were invited to participate from institutions such as local businesses and universities by advertising through leaflets and by word of mouth. The control group consisted only of participants who believed they were not persons who stuttered, and were entered into the study only after they were diagnosed by an experienced clinician as not having a stutter. Additional exclusion criteria for the AWS and control groups consisted of: (a) any present history of a physical or neurological disorder or condition (other than stuttering), (b) less than 18 years and older than 85 years, and (c) unable to speak English. The study received research ethics approval from the local institutional human research ethics committee and participants provided written consent before participating in the study. The two groups had similar educational and employment profiles. DEFINITION OF STUTTERING Stuttering was defined as a disorder in the rhythm of speech, in which the individual knows what he or she wishes to say, but is unable to say it because of an involuntary, repetitive prolongation or cessation of sound. Stuttering included repetitions of syllables, avoidance of words, substitutions, part-or-whole words, or phrases; prolongations of speech, or blocking of sounds. STUDY DESIGN AND PROCEDURE A group cohort design was used to ensure subjects were recruited according to the proportion of the age distribution for the community in which the study was conducted and AWS participants were stratified for age and sex. AWS attended a 2–3hr interview in which the participant and the interviewer engaged in an informal discussion for around 3min, which was audiotaped for the purposes of determining stuttering severity. Following this, participants completed a booklet of standardized psychological questionnaires. The control group experienced the same interview protocol as the AWS, except that a speech sample and stuttering specific information were not obtained. ASSESSMENT Demographic measures included age, sex, level of education, age at which stuttering was diagnosed, and employment status. A behavioral measure of stuttering severity was used, and this was calculated from the 3min recorded speech samples of conversational speech. From this sample frequency of stuttering (percent syllables stuttered or %SS) was calculated using a method with acceptable validity and reliability. Stuttering severity was calculated by an experienced clinician and inter- rater reliability was demonstrated by an experienced researcher who randomly reassessed 10% of the speech samples. 688 Blumgart et al. Depression and Anxiety All participants completed the Lifestyle Appraisal Questionnaire (LAQ), a standardized self-report health risk measure. The LAQ consists of a comprehensive measure of multiple health risk factors experienced over the past 8 weeks. It assesses multiple sources of health risks such as body mass index, diet, alcohol and nicotine intake, and so on. A higher score for the LAQ indicates elevated health risks. The LAQ has acceptable internal reliability, discriminate validity, and test–retest reliability. All 400 participants completed the following anxiety question- naires: (i) state–trait anxiety measured by the Spielberger State–Trait Anxiety Inventory, shown to be a valid and reliable measure. Although this measure has limitations, it was used as early anxiety studies in stuttering employed the state–trait measure. (ii) The Fear of Negative Evaluation—Long Form (FNE), a valid and reliable cognitive measure closely related to social anxiety.[26,27] The long- form FNE was used as prior research into the relationship between anxiety and stuttering has employed this scale. (iii) The Social Phobia and Anxiety Inventory, a validated and reliable measure of social anxiety.[28,29] Both the SP sub-scale and the difference score ([SP sub-score][Agoraphobia sub-score]) were used in the study. To reduce any selection biases in the sample when estimating SP prevalence, 50 AWS and 50 AWDNS were randomly selected from the two larger groups of 200 using a random number technique, and screened for SP using DSM IV guidelines for Axis I disorders. They were also screened for generalized anxiety disorder (GAD). The Psychiatric Diagnostic Screening Questionnaire (PDSQ) was em- ployed for the above purpose. The PDSQ has been shown to be a valid and reliable tool for diagnosing Axis I disorders. It was developed as a diagnostic screening tool to be used to facilitate the efficiency of conducting diagnostic evaluations. Zimmerman and Mattia  suggest using a cut-off score to screen for people who may have SP. They found a score of 4 out of 14 SP items provided adequate sensitivity; that is, it identified 91% of people with SP correctly. When comparing mean SP subscale scores for people with SP (n5145) with those without SP, they found those with SP scored a mean of 9.2 out of 14 items, whereas those without SP scored 4. Therefore, because of the risk of inflation of the PDSQ SP score due to elevated social anxiety associated with stuttering, we opted to use both the accepted cut-off score of 4 as well as a more stringent cut-off score of 9 based on the mean found in Zimmerman and Mattia’s study. A score of 7 out of 10 was used to screen for GAD. All 100 randomly selected participants took part in a structured interview using the relevant PDSQ SP and GAD items. For the assessment of specific fears related to SP, the PDSQ asks whether respondents ‘‘worry a lot about doing or saying something to embarrass yourself in any of the following specific situations?’’ The PDSQ then goes on to ask about eight specific fears typical of those mentioned in DSM criteria (see Table 3). STATISTICAL METHODS Mean values for the anxiety measures were calculated and overall differences between the two groups were tested by multivariate analyses of variance. The association between anxiety measures and demographics were determined by Pearson correlation analysis. Given that the PDSQ measure counts frequency of symptoms, Mann–Whitney U tests, w2 analysis, phi correlation (F), variance explained in the relationship (F2) and odds ratio were also used to investigate differences between the groups on DSM symptoms of SP and GAD. RESULTS Table 1 shows demographic information. Mean frequency of stuttering (%SS) for the AWS was in the low to moderate severity range of around 4%SS. Male stuttering severity was similar to the females, and there were no significant severity differences for age. Correlation analysis found that %SS, sex, birthplace, education, and employment were not significantly associated with any anxiety measure. There were no significant differences or interactions for health risks (LAQ scores) across sex or group. Health risks significantly increased with age in both groups: F(1,396)55.6, Po.05. ANXIETY DIFFERENCES Table 2 shows descriptive statistics for anxiety. The AWS were significantly more anxious than the AWDNS across all anxiety measures: Wilk’s l5.8, F(5,394)519.9, Po.001. Anxiety reduced with increasing age for all five anxiety measures across both groups: Wilk’s l5.95, F(5,392)54.1, Po.01. There were no significant interactions found for sex by group for any anxiety measure. Stuttering severity (%SS) was not found to be significantly associated with elevated anxiety. SP AND GAD DIFFERENCES The 50 AWS had a significantly greater number of SP symptoms than the controls (median AWS SP score57, median AWDNS SP score52, Mann– Whitney U5550, Z54.8, Po.001). Using the cut-off TABLE 1. Age, age diagnosed with stuttering, frequency of stuttering (%SS), and health risk status (LAQ) details for adults who stutter (AWS) and adults who do not stutter (AWDNS) Age (yrs) Age diagnosed (yrs) %SS LAQ Mean (SD) Mean (SD) Mean (SD) Mean (SD) AWS Males (n5151) 46.7 (16) 5.8 (2.6) 3.6 (2.7) 15.1 (6) Females (n549) 42.5 (16) 5.5 (3.2) 3.9 (3.2) 14.2 (7) Total (N5200) 45.7 (16) 5.7 (2.8) 3.7 (2.8) 14.9 (6) AWDNS Males (n5106) 48.1 (15) –– 14.7 (7) Females (n594) 46.1 (15) –– 15.6 (7) Total (N5200) 47.1 (15) –– 15.3 (7) 689Research Article: Social Anxiety and Stuttering Depression and Anxiety score of 4/14 items (Z4 possible SP;o4 unlikely SP), AWS were found to be significantly more likely to meet SP criteria than the controls: w2(1)525.2, Po.001; F5.5, F2 525%. Using this criterion, 80% of the AWS were found to meet PDSQ SP criteria (n540) compared to 30% (n515) of the AWDNS. Using the more stringent cut-off score of 9/14 items (Z9 possible SP; o9 unlikely SP), AWS were found to be significantly more likely to have SP than the controls: w2(1)523.5, Po.001; F5.48, F2 523%. Using this criterion, 46% (n523) of the AWS were found to meet PDSQ SP criteria, that is, having 9 SP symptoms, compared to 4% (n52) of the AWDNS. The odds of an AWS having increased SP symptoms was over 20 times that for AWDNS (odds ratio520.4, 95%CI54.5–93.5). Although AWS scored higher on the GAD items, there were no significant differences between groups for GAD symptoms. An alternative strategy to the employment of a PDSQ cut-off score for determining SP prevalence was used. This consisted of counting the number of participants who scored positive in the PDSQ items for the DSM SP diagnostic criteria (as for example, items within the MINI 5 Plus structured diagnostic interview for SP). The PDSQ covers all the core criteria for diagnosing SP in its 15 items. When this was analyzed, an SP prevalence of 40% was found for the AWS (20/50) compared to a 4% rate for the controls (2/50): w2(1)518.9, Po.001, F5.43, F2519%. GENERALIZED VERSUS SPECIFIC SP The number of participants who scored positive in the PDSQ specific fear items for the DSM SP diagnostic criteria were also counted. The number of subjects meeting DSM criteria for GSP (at least four specific fears) was then determined. This resulted in a GSP prevalence of 85% of those AWS with a positive SP diagnosis (17/20) and 50% of the AWDNS (1/2). The majority of AWS with SP were therefore diagnosed with a generalized form of SP. SPECIFIC SP SYMPTOMS Table 3 shows the comparison of the eight specific fears. AWS were significantly more likely to fear: public speaking (w2(1)59.1, Po.01), eating in public (w2(1)57.2, Po.01), saying something stupid in a group of people (w2(1)511.8, Po.001), asking ques- tions in a group of people (w2(1)525.1, Po.001), speaking at business meetings (w2(1)511.8, Po.001), and interacting at parties and social gatherings (w2(1)518.3, Po.001). There was no significant difference between groups for using a public toilet and writing in public. DISCUSSION The 200 AWS had similar education and health status to the controls. Male AWS were similar to the female AWS in terms of health risks and severity of stuttering. As expected, health risks increased in both groups as the age of the participants increased. Level of education, type of employment, place of birth, and sex were not found to be significantly related to anxiety levels. However, anxiety was significantly elevated in the AWS across all anxiety measures with moderate to large effect sizes occurring. These results confirm preliminary findings that stuttering is associated with abnormally elevated social anxiety.[10,21] AWS were also found to be significantly higher at risk of SP based on TABLE 2. Anxiety measures for adults who stutter (AWS) and adults who do not stutter (AWDNS) AWS (N5200) AWDNS (N5200) Anxiety measure Mean (SD; 95%CI) Mean (SD; 95%CI) ES Sign State anxiety 34.7 (13; 33–37) 30.2 (9; 29–32) .41 .02 Trait anxiety 39.7 (12; 38–41) 33.9 (9; 33–35) .64 .001 FNE 15.2 (9; 14–16) 10.2 (8; 9–11) .59 .001 SPAI SP score 50.5 (25; 47–54) 30.1 (20.6; 27–33) .93 .001 SPAI diff score 37.5 (20; 35–40) 18.8 (17; 16–21) 1.0 .001 Effect sizes and significant differences between the two groups are shown. SD5standard deviation; 95% CI595% confidence interval of the mean; ES5effect size. TABLE 3. Specific fears in which respondents worry a lot about embarrassing themselves, as measured by the PDSQ AWS AWDNS Specific fear No Yes No Yes w2 P-value Odds ratio Public speaking 15 35 30 20 9.1 .003 5.0 Eating in public 39 11 48 2 7.2 .008 6.8 Using public restrooms 46 4 49 1 1.9 .17 – Writing in public 44 6 48 2 2.2 .14 – Saying stupid things in a group 26 24 42 8 11.8 .001 4.8 Asking questions in a group 14 36 39 11 25.1 .000 9.1 Business meetings 20 30 37 13 11.8 .001 4.3 Social gatherings or parties 27 23 46 4 18.3 .000 9.8 Adults who stutter (AWS) are compared to the adults who do not stutter (AWDNS). w2, significance, and odds ratio (only for significant items) are shown. 690 Blumgart et al. Depression and Anxiety DSM criteria; that is, AWS were 20 times more at risk of having significantly elevated SP symptoms, whereas no significant differences were found between groups for GAD symptoms. AWS had significantly elevated specific fears compared to the controls (Table 3), except for using a public restroom and writing in public. These findings suggest AWS have significantly elevated risks of specific fears, and therefore they are potentially more at risk of having a generalized form of SP. Results confirmed this by showing that AWS who met criteria for SP were much more likely to have a generalized form of SP (85%). Younger AWS (less than 60 years) were found to be higher at risk of having elevated social anxiety compared to those aged 60 years or over. Kessler et al. investigated the prevalence of SP in the National Comorbidity Survey Replication study and also found that people less than 60 years (that is, non stuttering people) were greatest at risk of having a SP. Reasons for younger AWS having elevated social anxiety have not been investigated, so this remains an important avenue for further research. Stuttering severity (%SS) was not found to be related to any anxiety measure or increased SP symptoms. Those who stuttered mildly were just as likely to have elevated social and trait anxiety as were those with moderate or severe stuttering, and the converse was also true. This lack of a relationship between stuttering severity and social anxiety was also found by Stein et al. Therefore, the data does not allow one to conclude that increased stuttering severity significantly raises the risk of developing elevated social anxiety, and that mild stuttering decreases such a risk. Although this finding may seem counterintuitive, it suggests that stuttering can be a socially toxic disorder regardless of severity. The prevalence estimate of 80% using the PDSQ cutoff of four is most likely too high, and it is similar to the 75% estimate found by Stein et al. before they applied the modified DSM-IV criteria. Stein et al. concluded that around 44% of their sample met DSM-IV criteria for SP when taking into account excessive social anxiety relative to severity. In this study, the more stringent method of estimating SP provided a spot prevalence estimate of 46% for AWS and 4% for controls. The stuttering prevalence is similar to that found by Stein et al. and the control prevalence falls within accepted estimates. Based on the data obtained in this study, we believe at least 40% may be a valid estimate of SP in AWS. These findings have implications for diagnosing SP in AWS. First, with the DSM-IV diagnostic criteria as they currently exist, it is problematic to diagnose SP in people who have an Axis I disorder such as stuttering. Clarification is crucial given that most AWS presently do not commonly receive screening for SP, nor are they likely to receive psychological treatment shown to be effective for SP.[10,14] To address this situation, it would be desirable to have a more clarified diagnosis other than ‘‘anxiety disorder not otherwise specified’’ for AWS who meet DSM SP criteria. We suggest a diagnosis such as ‘‘SP associated with communication disorder.’’ It is hoped such a clarification of DSM differential diagnosis guidelines would improve the treatment of AWS who exhibit SP symptoms. Several limitations exist in this study. The SP spot prevalence estimate of at least 40% was derived using a screen assessment. Although the screen involved a diagnostic procedure, the screening procedure may have caused an inflation of the estimate. However, the 15 PDSQ SP items used in the structured interview screen match the essential DSM SP items found in alternative diagnostic interviews such as the Mini International Neuropsychiatric Interview diagnostic interview or the Structured Clinical Interview for DSM-IV Axis I Disorders. Second, only 100 of the 400 participants received the structured inter- view, thereby lowering the power of the study. However, these 100 were selected on a random basis, thereby theoretically reducing possible selection bias, and the power from the sub-groups to detect symptom differences between the groups was very high (490%) due to the substantial differences in symptoms between the two groups. CONCLUSION These findings strongly suggest that stuttering sub- stantially influences trait and social anxiety and that AWS have a significantly higher prevalence of SP than nonstuttering controls. Stuttering has recently been shown to lower quality of life in domains such as vitality, social and emotional functioning, and mental function- ing. Interestingly, a similar outcome has been found for nonstuttering people with SP. Therefore, as some have already argued,[8,9] the DSM diagnosis guidelines need to be reviewed with respect to the diagnosis of SP in AWS. If an AWS has SP but is not diagnosed as such due to confusion caused by DSM guidelines, this will more than likely limit their opportunities to receive appropriate pharmacological or psychological treatments shown to be effective for SP. It is reasonable to assume then that if left untreated for their SP symptoms, they will remain high at risk of increased anxiety and lowered quality of life.[11,15] Presently, it is a concern that treatment designed to lower stuttering may not sig- nificantly remove SP symptoms and treatment designed to lower SP may not significantly reduce stuttering severity. Clearly, improved diagnostic decisions in this area may help improve treatment efficacy. In conclusion, the prevalence of adult stuttering is around 1% of all adults. Hypothetically, in a country with 100 million adults, this means one million adults will be at risk of stuttering, and if our estimates are correct, possibly at least 400,000 of those adults will be at risk of developing SP, a very concerning statistic, especially when younger adults are most likely higher at risk. Furthermore, most of these will be at risk of having GSP, a more serious 691Research Article: Social Anxiety and Stuttering Depression and Anxiety form of SP. Because of this high risk, AWS who seek treatment should be routinely and comprehensively screened for their risk of elevated social anxiety. REFERENCES 1. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR). 4th ed. Washington, DC: APA; 2000. 2. Clark DM, Wells A. A cognitive model of social phobia. 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Depression and Anxiety Copyright of Depression & Anxiety (1091-4269) is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. ng. J Speech Lang Hear Res 2008;51:1451–1464. 11. Craig A, Blumgart E, Tran Y. The impact of stuttering on the quality of life in adult people who stutter. J Fluency Disord 2009;34:61–71. 12. Craig A, Hancock K, Tran Y, et al. Epidemiology of stuttering in the community across the entire lifespan. J Speech Lang Hear Res 2002;45:10