Predictors of panic attacks in adolescents

10-year research update review: the epidemiology of child and adolescent psychiatric disorders: II. Developmental epidemiology

OBJECTIVE

To describe the growth of developmental epidemiology in the past decade and to illustrate it with examples of recent studies.

METHOD

A review of publications on developmental epidemiology in the past 10 years and a discussion of some key examples.

RESULTS

The authors describe how the interaction between developmental psychopathology and psychiatric epidemiology has produced developmental epidemiology, the study of patterns of distribution of psychiatric disorders in time as well as in space. They give two examples of the kinds of questions that developmental epidemiology can help to answer: (1) Is the prevalence of autism increasing? Does the use of vaccines explain the increase? (2) Is there an epidemic of child and adolescent depression? Finally, they describe two areas of science that are beginning to inform developmental epidemiology: molecular genetics and the use of biological measures of stress.

CONCLUSIONS

While child and adolescent psychiatric epidemiology continues, as described in the first of these reviews, to address questions of prevalence and burden, it has also expanded into new areas of research in the past decade. In the next decade, longitudinal epidemiological data sets with their rich descriptive data on psychopathology and environmental risk over time and the potential to add biological measures will provide valuable resources for research into gene-environment correlations and interactions.

Vulnerability factors for anxiety disorders in children and adolescents

With the maturation of community studies of adults in the past decade, there has been growing awareness of the importance of the magnitude and impact of anxiety disorders in the general population. The convergence of findings from adult and child epidemiology reveals that the onset of anxiety disorders occurs in childhood, and a substantial proportion of youth with anxiety continues to manifest lifelong problems with anxiety and other mental disorders. In this article, the major risk factors for the development of anxiety disorders in childhood and adolescence are reviewed.

Separation anxiety disorder, panic disorder, and school refusal

Studies attest to the chronic nature of anxiety in youth. Consequently, there is a growing literature examining causative pathways to these disorders and efficacious treatments for them. This review examines separation anxiety disorder, a commonly occurring childhood anxiety disorder, and panic disorder, a more rare anxiety disorder in youth. Finally, school refusal, which may be tied to an internalizing or externalizing disorder or no disorder at all, is examined.

Imagined risk of suffocation as a trigger for hyperventilation

OBJECTIVE

Although hyperventilation has been hypothesized to play a role in many pathologies, its critical triggers remain poorly understood. The present experiment aimed to test whether stronger hyperventilation responses occur in response to suggested risk of suffocation compared with other fearful situations in high- and low-trait anxious women.

METHODS

Fractional end-tidal CO2-concentration (FetCO2), respiratory frequency, and inspiratory volume were measured nonintrusively in high- (n = 24) and low- (n = 24) trait anxious women during imagery of 3 fear, 1 tension, 1 depressive, and 3 relaxation scripts. The fear scripts were equal in ratings of unpleasantness and arousal but differed regarding the inclusion of suggested risk of suffocation and entrapment. After each imagery trial, participants rated the emotional dimensions of pleasantness, arousal, and dominance and the vividness of their imagery.

RESULTS

Decreases in FetCO2 occurred in all fear scripts. High-trait anxious women showed a stronger reduction in FetCO2 compared with low-trait anxious women during the fear script suggesting risk of suffocation but not during the other fear scripts. This effect was unrelated to any of the self-reported fear ratings. Self-reported fear of entrapment was associated with an overall lower FetCO2 but not with enhanced reactivity to imagined entrapment.

CONCLUSION

High-trait anxiety is associated with stronger respiratory responsivity to imagined risk of suffocation and may constitute a specific vulnerability factor for the development of panic disorder and claustrophobia.

Taxonicity of anxiety sensitivity: an empirical test among youth

Taxometric coherent cut kinetic analyses were used to test the latent structure of anxiety sensitivity (AS) among 371 youth. Anxiety sensitivity was indexed by the 18-item Childhood Anxiety Sensitivity Index (CASI; Silverman et al., J. Clin. Child Psychol. (1991), 20, 162-168). Two sets of manifest indicators of AS were constructed using the CASI: (1) three item-parcel manifest indicators: disease concerns, unsteady concerns, and mental illness concerns; and (2) nine single-item indicators representing each of these three facets of AS. Results from standard and short-scale MAXCOV procedures, internal consistency tests, analyses of simulated Monte Carlo data, and MAMBAC external consistency tests indicated that the latent structure of anxiety sensitivity among youth was taxonic. Estimated base rate of the observed AS taxon ranged between 13.6 and 16.5%. The present findings are discussed in terms of theoretical implications for the study of AS and vulnerability for anxiety psychopathology.

Anxiety sensitivity in children of panic disorder patients

Anxiety sensitivity (AS), which refers to the tendency to interpret anxiety-related bodily sensations as having potentially harmful somatic, psychological or social consequences, has been proposed as a vulnerability factor for the development of panic disorder (PD). The current study examined the anxiety sensitivity levels in children of parents with panic disorder. Children of panic disorder patients (n = 68) and children of healthy parents (n = 68) filled out the Childhood Anxiety Sensitivity Index, while parents completed the Anxiety Sensitivity Index. Children of parents with panic disorder did not display higher levels of anxiety sensitivity than children of healthy parents. Furthermore, no association between anxiety sensitivity levels of parents with panic disorder and their children was found. Anxiety sensitivity is not clearly manifest in children of parents with panic disorder and might be a developing vulnerability factor that may increase towards late adolescence or early adulthood.

Anxiety Disorders in Childhood: Casting a Nomological Net

Empirical research highlights the need for improving the childhood anxiety disorder diagnostic classification system. In particular, inconsistencies in the stability estimates of childhood anxiety disorders and high rates of comorbidity call into the question the utility of the current DSM criteria. This paper makes a case for utilizing a nomological net model for advancing the understanding of childhood anxiety disorders. In this article, we discuss measurement and assessment issues related to improving the childhood anxiety disorder diagnostic system and show how these issues can be addressed by employing the nomological net of childhood anxiety. Because employing the nomological net involves drawing from etiological process theories to facilitate classification and assessment, an integrative model of childhood anxiety disorders is presented as a tentative heuristic. Then evidence for the existing symptom sets is discussed in the context of how process theory mechanisms may be utilized to improve classification and assessment. Testable hypotheses are presented. Measurement, disorder definition, treatment, and policy implications are also discussed.

A cross-sectional evaluation of the factorial invariance of anxiety sensitivity in adolescents and young adults

This study examined the cross-sectional factorial invariance of anxiety sensitivity in an ethnically diverse sample of adolescents (n = 173; mean age 15.5 years) and young adults (n = 291; mean age 20.1 years). Research in adult and youth samples suggests that anxiety sensitivity is best understood as a hierarchical construct with several lower-order factors. Factor models based on previous research using both adult and youth samples were compared and a hierarchical model with three lower-order factors provided the best fit to the data. Results supported the hypothesis that the factor structure of the Anxiety Sensitivity Index was invariant across age and gender. The factor scores also demonstrated differential correlations with symptoms of anxiety and depression. Results are discussed with regard to construct validation and understanding the structure of anxiety sensitivity in youth.

A prospective evaluation of agoraphobia and depression symptoms following panic attacks in a community sample of adolescents

In a community sample of high schoolers who experienced their first panic attack, we examined the prospective relationships among pre-panic vulnerabilities, panic attack severity, and post-panic agoraphobia and depression symptoms. Students were evaluated yearly over 4 years to test the following four hypotheses: (1) pre-panic anxiety sensitivity, negative affect, and childhood behavioral inhibition will serve as vulnerabilities that predict agoraphobia and depression symptoms following a panic attack; (2) these vulnerabilities will lead to more severe panic attacks; (3) severe and spontaneous panic attacks will predict subsequent agoraphobia and depressive symptoms; and (4) the interaction between panic severity and vulnerabilities will be associated with worse outcomes following a panic attack. Results supported the first three hypotheses, but no evidence emerged for an interactive effect. Findings are discussed in light of recent modernized classical conditioning models that address factors contributing to development of more severe panic related psychopathology after panic attacks.

Diathesis stress model for panic-related distress: a test in a Russian epidemiological sample

To investigate a cognitive diathesis-stress model, the present study evaluated the main and interactive effects of anxiety sensitivity (AS) and exposure to aversive conditions (past month) in predicting theoretically relevant panic vulnerability variables in an epidemiologically defined sample from Russia (N = 390). Consistent with expectation, findings suggested that the combination of high levels of exposure to aversive conditions and high AS physical concerns predicted panic attacks (past week) and agoraphobic avoidance above and beyond the variance accounted for by negative affect. These findings are discussed in relation to biopsychosocial theories of panic disorder, which emphasize the importance of both a cognitive diathesis and stress component in the pathogenesis of the disorder.

Is premenstrual dysphoria a variant of panic disorder? A review

Patients with premenstrual dysphoric disorder (PMDD) and patients with panic disorder (PD) both experience high rates of panic attacks in laboratory panic provocation studies. Recently, this shared elevated rate of challenge-induced panic has received increasing attention. Researchers have suggested that PMDD and panic disorder may share a pathophysiological or psychobiological link. The purpose of this paper is to review the findings from PMDD challenge studies and the theories advanced to connect PMDD to panic disorder. Taken together, the results of the PMDD challenge studies confirm that agents that incite panic in PD patients do so as well in PMDD women. This shared elevated challenge-induced panic cannot be accounted for by explanations such as a history of PD in PMDD women. None of the physiological theories as currently expressed--suffocation false alarm, gamma-aminobutyric acid (GABA), noradrenergic, serotonergic, and cholecystokinin--yet provides a compelling candidate to account for shared elevated challenge-induced panic in PD and PMDD patients. Psychological perspectives on panic emphasize that bodily sensations themselves can cause fear. Researchers have yet to apply several influential psychological approaches--conditioning, catastrophic misinterpretation, and anxiety sensitivity--to PMDD patients. Because psychological factors influence anxious responding in challenge studies, the search for the biological abnormality best accounting for PMDD panic might benefit from a reframing of the question to one that considers the psychological perspective as well.

Phenomenology of panic disorder in youth

We compared the demographic and clinical characteristics of youth with panic disorder (PD) (n=42), non-panic anxiety (n=407), and non-anxiety psychiatric disorders (n=1,576). Subjects were recruited from a mood and anxiety disorders clinic and assessed with the KSADS-P. In this large clinical sample, approximately 2% of the patients had PD. Most of these patients were adolescent, female, and Caucasian. PD was associated frequently with comorbid bipolar disorder, MDD, and other anxiety conditions, in particular general anxiety and separation anxiety disorders. Palpitations, chest pain, faintness, and trembling/shaking were the most frequent PD symptoms. In comparison with the other groups, youths with PD were significantly slightly older, Caucasian, and have more comorbid bipolar disorder. Subjects with both panic and non-panic anxiety disorders were more likely to have comorbid major depression and conduct disorders than those with other non-anxiety disorders.

Anxiety sensitivity in African-American adolescents: evidence of symptom specificity of anxiety sensitivity components

OBJECTIVE

To examine the specificity of components of anxiety sensitivity (phrenophobia, fear of cardiovascular sensations, and fear of unsteadiness) to anxiety and depression in a sample of African-American adolescents.

METHOD

Participants were 527 African-American adolescents (238 females, mean age 13.8 years) who were originally recruited as first graders in 1993 to 1994 for participation in the second-generation Johns Hopkins Prevention Intervention Research Center trials. Youths completed measures of anxiety sensitivity and anxious and depressive symptoms in the spring of 2001. Associations between anxiety sensitivity and depression and anxiety were examined using hierarchical linear regressions.

RESULTS

Anxiety sensitivity as a unitary construct was positively associated with symptoms of anxiety after adjusting for symptoms of depression. Fear of unsteadiness showed specificity to anxiety after adjusting for depression and phrenophobia. Phrenophobia was positively associated with anxiety and depression, after adjusting for the other symptom and fears of physical sensations.

CONCLUSIONS

Specificity of anxiety sensitivity to anxiety in a sample of African-American adolescents furthers understanding of the nature of anxiety sensitivity in this group and the potential roles of components of anxiety sensitivity in the development of psychopathology in general.

Parent-reported predictors of adolescent panic attacks

OBJECTIVE

To identify parent-reported risk factors for adolescent panic attacks.

METHOD

Structured diagnostic interviews were obtained from 770 parents of participants in a school-based risk factor study for adolescent panic. Parent-reported risk factors assessed included characteristics of the child (negative affect, separation anxiety disorder [SAD], childhood chronic illness, and childhood loss) as well as characteristics of the parent (parental panic disorder or agoraphobia [PDA], parental major depression, and parental chronic illness).

RESULTS

Bivariate predictors of adolescent panic attacks included parent history of PDA, parent history of chronic illness, child negative affect, and child SAD. Using signal detection methods, three subgroups of participants at risk for panic attacks were identified. Fifty-eight percent of adolescents with panic attacks belonged to one of these high-risk groups. Adolescents with a positive parental history of PDA were at highest risk: 24% of this group experienced panic attacks. Among those without a positive parental history of PDA, those with high childhood negative affect or history of SAD were at increased risk for panic attacks (14% and 20%, respectively).

CONCLUSIONS

The use of parent-reported data provides cross-validation for previously identified risk factors of adolescent panic attacks. Signal detection results suggest there are multiple paths (equifinality) to the development of adolescent panic attacks.

Coming to Terms With Risk Factors for Eating Disorders: Application of Risk Terminology and Suggestions for a General Taxonomy

The aims of the present review are to apply a recent risk factor approach (H. C. Kraemer et al., 1997) to putative risk factors for eating disorders, to order these along a timeline, and to deduce general taxonomic questions. Putative risk factors were classified according to risk factor type, outcome (anorexia nervosa, bulimia nervosa, binge-eating disorder, full vs. partial syndromes), and additional factor characteristics (specificity, potency, need for replication). Few of the putative risk factors were reported to precede the onset of the disorder. Many factors were general risk factors; only few differentiated between the 3 eating disorder syndromes. Common risk factors from longitudinal and cross-sectional studies were gender, ethnicity, early childhood eating and gastrointestinal problems, elevated weight and shape concerns, negative self-evaluation, sexual abuse and other adverse experiences, and general psychiatric morbidity. Suggestions are made for the conceptualization of future risk factor studies.

Differences between those who panic by day and those who also panic by night

This study examined the characteristics, correlates, background demographic, and personality variables associated with panic among those who panic exclusively from a waking state and those who also panic out of sleep. Participants were recruited through advertising in print media and through anxiety/panic support groups. Some group differences in the characteristics of panic and the associations between panic and other variables were found. Specifically, levels of anxiety sensitivity were higher, panic duration was longer, and panic was less strongly related to catastrophic cognitions for the group that experienced nocturnal panic. These differences are cautiously interpreted as not supporting a "strong" cognitive theory of panic initiation.

Panikanfälle und Angstsensitivität im Jugendalter

Zusammenfassung. Theoretischer Hintergrund: Das Jugendalter ist mit einem substantiellen Anstieg in der Häufigkeit von Panikanfällen verbunden. Erscheinungsbild und klinische Merkmale von Panikanfällen in dieser Altersgruppe sind noch kaum erforscht. Fragestellung: Neben der Häufigkeit von Panikanfällen wurde v.a. untersucht, ob sich plötzliche Panikanfälle von situationsgebundenen Panikanfällen im Erscheinungsbild sowie in Massen zur Angstsensitivität unterscheiden. Methode: Es wurden 1268 Schüler (12-16 Jahre alt) anhand eines Fragebogens befragt. Ergebnisse: 55% der Jugendlichen hatten bereits einen Panikanfall erlebt. Jugendliche mit plötzlichen Panikanfällen berichteten im Unterschied zu Jugendlichen mit situationsgebundenen Panikanfällen signifikant häufiger kognitive Symptome, die die Bedrohung der körperlichen Unversehrtheit beinhalteten. Jugendliche mit plötzlichen Panikanfällen bzw. Panikstörung zeigten die höchsten Mittelwerte in Massen zur Angstsensitivität und Depressivität. Schlussfolgerungen: Die Befunde sprechen für eine zentrale Rolle kognitiver Symptome und stehen damit im Einklang mit psychologischen Modellvorstellungen zur Panikstörung wie sie für Erwachsene formuliert wurden.

The Composite International Diagnostic Interview (CIDI-Auto): problems and remedies for diagnosing panic disorder and social phobia

In a recent study of treatment for panic disorder in primary care, the Composite International Diagnostic Interview (CIDI-Auto) was used to provide psychiatric diagnoses. However, during and after data collection, it was discovered that the CIDI appeared to place, or fail to place, a substantial number of people into diagnostic categories in ways that conflicted with the investigators' clinical experience. The wording of questions in the panic module, coupled with a lack of structured follow-up probes, resulted in apparent false negatives for panic disorder. Moreover, patients who would otherwise meet criteria for panic disorder or social phobia did not receive a diagnosis based on rules that may be discordant with clinical practice and, at times, the design of the DSM-IV. For this study, changes were made to the interview, including additional probes for the panic disorder module and modification of the decision rules used to assign or rule out diagnoses of panic disorder and social phobia. The changes resulted in greater inclusion of patients in the panic disorder and social phobia diagnostic categories and we argue that these changes to the CIDI-Auto increase the clinical validity of this instrument. We did not examine the false positive rate for the unmodified or modified CIDI, but this is an important issue that needs to be evaluated in future research.

Anxiety sensitivity in adolescents at risk for psychopathology

Examined the associations of adolescents' self-reported anxiety sensitivity with semi-structured, interview-based anxiety and depressive symptoms and anxiety disorders. The sample included 121 adolescents and their parents who participated in a larger epidemiological, high-risk family study of substance abuse and anxiety disorders (Merikangas, Dierker, & Szatmari, 1998). A series of hierarchical multiple regressions revealed the incremental validity of anxiety sensitivity, beyond the contribution of self-rated anxiety, to anxiety symptoms and comorbid anxiety disorders. Furthermore, familial risk for anxiety moderated the association between anxiety sensitivity and number of anxiety symptoms as well as number of comorbid anxiety disorders. Analyses of high- and low-risk groups demonstrated that the association between anxiety sensitivity and anxiety symptoms and disorders was evident in high-risk adolescents only. Although self-reported anxiety was associated with depressive symptoms, anxiety sensitivity was not. Results from this investigation further support the utility of assessing anxiety sensitivity in an adolescent population and suggest it as a trait marker of anxiety among at-risk individuals.

Toward an empirical definition of pediatric PTSD: the phenomenology of PTSD symptoms in youth

OBJECTIVE

To examine the frequency and intensity of posttraumatic stress disorder (PTSD) symptoms and their relation to clinical impairment, to examine the requirement of meeting all DSM-IV symptom cluster criteria (i.e., criteria B, C, D), and to examine the aggregation of PTSD symptom clusters across developmental stages.

METHOD

Fifty-nine children between the ages of 7 and 14 years with a history of trauma and PTSD symptoms were assessed with the Clinician-Administered PTSD Scale for Children and Adolescents.

RESULTS

Data support the utility of distinguishing between the frequency and the intensity of symptoms in the investigation of the phenomenology of pediatric PTSD. Children fulfilling requirements for two symptom clusters did not differ significantly from children meeting all three cluster criteria with regard to impairment and distress. Reexperience (cluster B) showed increased aggregation with avoidance and numbing (cluster C) and hyperarousal (cluster D) in the later stages of puberty.

CONCLUSIONS

Frequency and intensity of symptoms may both contribute to the phenomenology of pediatric PTSD. Children with subthreshold criteria for PTSD demonstrate substantial functional impairment and distress.

The relationship between anxiety sensitivity and fear of pain in healthy adolescents

The present study investigated the relationship between anxiety sensitivity and fear of pain in a large group of healthy adolescents (N=200). Participants completed the childhood anxiety sensitivity index for children-revised, a questionnaire measuring four specific domains of anxiety sensitivity: fear of cardiovascular symptoms, fear of respiratory symptoms, fear of cognitive dyscontrol, and fear of publicly observable anxiety symptoms, and a simplified version of the pain anxiety symptoms scale, a self-report instrument assessing pain-related anxiety and avoidance (i.e. fear of pain). In line with previous research in adult populations, it was found that anxiety sensitivity is substantially and positively related to fear of pain. Even when controlling for other potential predictors of fear of pain (i.e. pain symptoms, other somatization symptoms, trait anxiety, and panic disorder symptoms), anxiety sensitivity appeared to declare a unique proportion of the variance in pain anxiety symptoms.

Relations between anxiety sensitivity and panic symptoms in nonreferred children and adolescents

Anxiety sensitivity (AS), the fear of anxiety-related sensations, has been posited to be a cognitive risk factor for the development of anxiety disorders but has been understudied in youth. The purpose of the present investigations was to evaluate relations between AS and panic symptoms in nonreferred children and adolescents. In Study 1, (N = 113, mean age, 13.98). scores on the Childhood Anxiety Sensitivity Index (CASI) predicted the experience of uncued panic attacks after controlling for general anxiety and depression, although the total variance accounted for was small. In Study 2 (N = 52; mean age, 9.48), the Panic/ Agoraphobia subscale of the Spence Children's Anxiety Scale was used as the criterion variable. CASI score again predicted panic symptoms after controlling for trait anxiety and depression. Identification of a risk factor for panic attacks and panic disorder in youth will have important implications for etiologic theory, intervention, and prevention.

Comorbidity of mood and anxiety disorders

This article reviews data on the prevalence of panic, social phobia, generalized anxiety, and posttraumatic stress disorder, and research documenting the comorbidity of these disorders with major depression (MDD). These anxiety disorders are frequently comorbid with MDD, and 50-60% of individuals with MDD report a lifetime history of one or more of these anxiety disorders. The anxiety disorders are also highly correlated with one another, and approximately one-quarter to one-half of individuals with each of the anxiety disorders report a lifetime history of an alcohol or substance use disorder. Anxiety disorders rarely exist in isolation, with several studies reporting that over 90% of individuals with anxiety disorders have a lifetime history of other psychiatric problems. Implications for research are discussed, including the potential benefit of using combined categorical and dimensional rating scale approaches in future genetic, biochemical, neuroimaging, and treatment studies. The clinical implications of the findings are also discussed, and the results of recent clinical trials summarized. Available data suggests selective serotonin reuptake inhibitors are the first-line pharmacological treatment for these disorders, and that newer serotonin and norepinephrine reuptake inhibitors show significant promise, especially for comorbid cases. Comorbidity among depression and anxiety disorders is associated with greater symptom severity, and a considerably higher incidence of suicidality. Increased public awareness about these disorders and the availability of effective treatments is sorely needed.

A modern learning theory perspective on the etiology of panic disorder

Several theories of the development of panic disorder (PD) with or without agoraphobia have emerged in the last 2 decades. Early theories that proposed a role for classical conditioning were criticized on several grounds. However, each criticism can be met and rejected when one considers current perspectives on conditioning and associative learning. The authors propose that PD develops because exposure to panic attacks causes the conditioning of anxiety (and sometimes panic) to exteroceptive and interoceptive cues. This process is reflected in a variety of cognitive and behavioral phenomena but fundamentally involves emotional learning that is best accounted for by conditioning principles. Anxiety, an anticipatory emotional state that functions to prepare the individual for the next panic, is different from panic, an emotional state designed to deal with a traumatic event that is already in progress. However, the presence of conditioned anxiety potentiates the next panic, which begins the individual's spiral into PD. Several biological and psychological factors create vulnerabilities by influencing the individual's susceptibility to conditioning. The relationship between the present view and other views, particularly those that emphasize the role of catastrophic misinterpretation of somatic sensations, is discussed.