A general anxiety-prone cognitive style in anxiety disorders

Anxiety disorders and GABA neurotransmission: a disturbance of modulation

Lines of evidence coming from many branches of neuroscience indicate that anxiety disorders arise from a dysfunction in the modulation of brain circuits which regulate emotional responses to potentially threatening stimuli. The concept of anxiety disorders as a disturbance of emotional response regulation is a useful one as it allows anxiety to be explained in terms of a more general model of aberrant salience and also because it identifies avenues for developing psychological, behavioral, and pharmacological strategies for the treatment of anxiety disorder. These circuits involve bottom-up activity from the amygdala, indicating the presence of potentially threatening stimuli, and top-down control mechanisms originating in the prefrontal cortex, signaling the emotional salience of stimuli. Understanding the factors that control cortical mechanisms may open the way to identification of more effective cognitive behavioral strategies for managing anxiety disorders. The brain circuits in the amygdala are thought to comprise inhibitory networks of γ-aminobutyric acid-ergic (GABAergic) interneurons and this neurotransmitter thus plays a key role in the modulation of anxiety responses both in the normal and pathological state. The presence of allosteric sites on the GABAA receptor allows the level of inhibition of neurons in the amygdala to be regulated with exquisite precision, and these sites are the molecular targets of the principal classes of anxiolytic drugs. Changes in the levels of endogenous modulators of these allosteric sites as well as changes in the subunit composition of the GABAA receptor may represent mechanisms whereby the level of neuronal inhibition is downregulated in pathological anxiety states. Neurosteroids are synthesized in the brain and act as allosteric modulators of the GABAA receptor. Since their synthesis is itself regulated by stress and by anxiogenic stimuli, targeting the neurosteroid-GABAA receptor axis represents an attractive target for the modulation of anxiety.

Can levels of a general anxiety-prone cognitive style distinguish between various anxiety disorders?

BACKGROUND

The question of whether certain anxiety disorders are especially related to a cognitive style characterized by an exaggerated perception of threat and appraisal of the future as excessively unpredictable (general anxiety-prone cognitive style) remains open.

OBJECTIVES

This study aimed to compare patients with generalized social anxiety disorder (SAD), generalized anxiety disorder (GAD), panic disorder with agoraphobia (PDA), and panic disorder without agoraphobia (PD) in terms of the levels of general anxiety-prone cognitive style when the severity of general distress and psychopathology is controlled for and to ascertain whether a co-occurring depressive disorder contributes substantially to the levels of this cognitive style.

METHODS

The Anxious Thoughts and Tendencies Scale, a measure of a general anxiety-prone cognitive style, and Symptom Checklist 90-Revised were administered to 204 patients with various anxiety disorders who attended an outpatient anxiety disorders clinic and were diagnosed based on a semistructured diagnostic interview.

RESULTS

Patients with principal diagnoses of SAD and GAD had a more prominent general anxiety-prone cognitive style than patients with principal diagnoses of PD and PDA when the severity of general distress and psychopathology was controlled for. The presence or absence of a co-occurring depressive disorder had no bearing on this finding.

CONCLUSIONS

The general cognitive component characterizes SAD and GAD more than it does PD and PDA, and a co-occurring depressive disorder does not affect this finding. These results have implications for distinguishing between various anxiety disorders.

Cognitive style, alprazolam plasma levels, and treatment response in panic disorder

This study investigated an anxiety-prone cognitive style (measured by the Anxious Thoughts and Tendencies Questionnaire, AT&T) as a predictor of the acute response to increasing alprazolam plasma levels in panic disorder. Panic disorder patients (n=26) were treated with escalating doses of alprazolam for 4 weeks, then a fixed dose of 1 mg four times a day for 4 weeks. At 0, 1, 2, 3, 4, 6, and 8 weeks, trough alprazolam plasma levels; clinical, self-report, and performance measures; and vital signs were assessed. Panic attack data were from daily diaries. The repeated response measures were analyzed in relation to alprazolam plasma levels using SAS GENMOD, with patients classified as high or low on the baseline AT&T. Panic attacks, anticipatory anxiety, fear, avoidance, overall agoraphobia, the Hamilton Anxiety Rating Scale, and clinicians' global ratings improved with increasing alprazolam plasma levels. Hopkins Symptom Checklist-90 Anger-Hostility; Profile of Mood States Vigor, Confusion, and Friendliness; and speed and accuracy of performance worsened. Patients with high AT&T scores were worse throughout the study on situational panics, fear, avoidance, overall agoraphobia, the Hamilton Anxiety Rating Scale, the Hamilton Rating Scale for Depression, and Clinical Global Improvement; most Hopkins Symptom Checklist-90 clusters; Profile of Mood States Anxiety, Depression, and Confusion; and Continuous Performance Task omissions. We conclude that in panic disorder: (1) alprazolam has a broad spectrum of clinical activity related to plasma levels in individual patients; (2) sedation, disinhibition, and performance deficits may persist for at least a month after dose escalation ends; (3) marked anxiety-prone cognitions predict more symptoms throughout treatment, but do not modify the response to alprazolam and therefore should not influence the choice of alprazolam as treatment.

Abrupt discontinuation of alprazolam and cognitive style in patients with panic disorder: early effects on mood, performance, and vital signs

The objective of this study was to ascertain the relationship of alprazolam plasma levels and an anxiety-prone cognitive style to the characteristics and severity of early withdrawal after abrupt discontinuation of alprazolam in 26 patients with panic disorder. After 8 and 9 weeks of fixed-dose treatment, patients were hospitalized for 24 hours. On 1 admission, ordered at random, treatment was maintained; on the other, placebo was substituted double blind. The Anxious Thoughts and Tendencies questionnaire was administered before treatment. Alprazolam plasma levels were measured 7 times on the day after each admission. Before each blood sampling, the Profile of Mood States and performance tasks were administered, and vital signs were recorded. On the day after abrupt discontinuation of alprazolam, Profile of Mood States anxiety, depression, fatigue, and confusion increased; vigor and elation decreased; speed on the digit symbol substitution task improved; and systolic blood pressure increased substantially over time. High Anxious Thoughts and Tendencies scores were related specifically to more anxiety. Our findings (1) confirm that dysphoric mood, fatigue, low energy, confusion, and elevated systolic blood pressure are part of the early syndrome of withdrawal from alprazolam in patients with panic disorder, notably as the drop in plasma levels approaches 50%; (2) indicate a psychomotor deficit persisting beyond dose stabilization; (3) suggest that an anxiety-prone cognitive style measurable before undertaking treatment may be a risk factor for more severe anxiety upon discontinuation; and (4) provide a rationale for applying cognitive behavior therapy during benzodiazepine taper.

Cognitive specificity of anxiety disorders: a review of selected key constructs

Cognitive models of anxiety disorders propose that certain cognitive constructs, that is, underlying beliefs and cognitive processes, may be specific for particular disorders. In this article, we review the specificity of four representative cognitive constructs-anxiety sensitivity, pathological worry, intolerance of uncertainty, and thought-action fusion-for particular disorders. Conceptual overlap, inconsistent definitions, and insufficient consideration of the components of these constructs are limitations of the existing literature. We suggest that the constructs are unlikely to be pathognomonic for any given disorder or to occur in isolation. Rather, the association of each cognitive construct is evident, to varying degrees, with different disorders. Relative to other disorders, anxiety sensitivity is to a certain extent specific for panic disorder, as are pathological worry for generalized anxiety disorder, intolerance of uncertainty for generalized anxiety disorder and obsessive-compulsive disorder, and thought-action fusion for obsessive-compulsive disorder. We discuss the implications of these findings for diagnostic systems and treatment, and suggest areas for further research.

Psychopathology of panic attacks in panic disorder

PURPOSE

This study examined the relationships among certain subtypes of panic attacks (full vs. limited symptom; spontaneous vs. situational) and between these subtypes, panic disorder subtypes, and other characteristics of panic disorder, especially agoraphobia.

METHOD

Data were drawn from a large (n = 1,168) treatment study of panic disorder in which panic attacks were carefully subtyped and counted using a diary. Relationships between variables at baseline were examined primarily using non-parametric methods, and the course of improvement for panic subtypes among completers was plotted.

RESULTS

The median number of spontaneous panic attacks per week at baseline was similar among patients with panic disorder without agoraphobia (PD), limited phobic avoidance (PDL), and agoraphobia (PDA). The median number of situational attacks and the median agoraphobia ratings rose progressively across diagnostic subtypes. Anticipatory anxiety, HAM-A, HAM-D, and disability scores were higher in PDA than in PD. Full and limited symptom panic attacks were positively correlated. The proportion of total attacks that were limited rose during the first two weeks of treatment, suggesting conversion of full to limited symptom attacks before complete disappearance. Spontaneous and situational attacks were correlated minimally or not at all. Agoraphobia ratings were more positively correlated with situational than with spontaneous panic attacks. Few of the correlations among measures at baseline were high.

CONCLUSIONS

Full and limited symptom panic attacks differ primarily in severity. Spontaneous and situational attacks are relatively independent, and situational attacks are more closely related to agoraphobia. These findings are consistent with previous work suggesting that spontaneous attacks reflect a biological component, whereas situational attacks reflect a cognitive component in the psychopathology-- and possibly the pathogenesis-- of panic disorder. This provides a rationale for the use of combined pharmacotherapy and psychotherapy in the treatment of panic disorder. Future investigations of panic disorder should carefully separate panic attack subtypes.

Influence of psychiatric comorbidity on recovery and recurrence in generalized anxiety disorder, social phobia, and panic disorder: a 12-year prospective study

OBJECTIVE

The authors sought to observe the long-term clinical course of anxiety disorders over 12 years and to examine the influence of comorbid psychiatric disorders on recovery from or recurrence of panic disorder, generalized anxiety disorder, and social phobia.

METHOD

Data were drawn from the Harvard/Brown Anxiety Disorders Research Program, a prospective, naturalistic, longitudinal, multicenter study of adults with a current or past history of anxiety disorders. Probabilities of recovery and recurrence were calculated by using standard survival analysis methods. Proportional hazards regression analyses with time-varying covariates were conducted to determine risk ratios for possible comorbid psychiatric predictors of recovery and recurrence.

RESULTS

Survival analyses revealed an overall chronic course for the majority of the anxiety disorders. Social phobia had the smallest probability of recovery after 12 years of follow-up. Moreover, patients who had prospectively observed recovery from their intake anxiety disorder had a high probability of recurrence over the follow-up period. The overall clinical course was worsened by several comorbid psychiatric conditions, including major depression and alcohol and other substance use disorders, and by comorbidity of generalized anxiety disorder and panic disorder with agoraphobia.

CONCLUSIONS

These data depict the anxiety disorders as insidious, with a chronic clinical course, low rates of recovery, and relatively high probabilities of recurrence. The presence of particular comorbid psychiatric disorders significantly lowered the likelihood of recovery from anxiety disorders and increased the likelihood of their recurrence. The findings add to the understanding of the nosology and treatment of these disorders.

Anxious Thoughts and Tendencies Scale: an investigation of factor structure and the psychometric properties on the basis of an Australian sample

BACKGROUND

The factor structure and psychometric properties of the revised Anxious Thoughts and Tendencies Scale (AT&T) is investigated.

METHODS

An Australian sample of 215 students and 33 patients diagnosed with an anxiety disorder completed a battery of anxiety-related questionnaires.

RESULTS

Factor analysis indicated one factor, which accounted for 38% of the variance and had high internal consistency and reliability. Significant relationships were found with measures of anxiety, anxiety sensitivity, catastrophic cognitions, fear and depression. The AT&T discriminated between students and patients, and between students with high or low levels of anxiety and fear.

LIMITATIONS

The size of the clinical sample was very small and the study needs to be replicated with a large and carefully recruited clinical sample.

CONCLUSIONS

These results support the AT&T as a valuable and psychometrically sound measure of the cognitive aspects of anxiety.

The N200 abnormalities of auditory event-related potentials in patients with panic disorder

Cognitive impairment in patients with panic disorder (PD) has been studied using event-related potentials (ERPs). However, previous studies obtained ERP data only at a few scalp sites, and seldom investigated N200 measurements from the difference waveforms. In the present study, auditory ERPs were recorded at 16 scalp sites during an active discrimination task of oddball paradigm. Fourteen PD patients (8 with agoraphobia; 6 without agoraphobia) were compared with 14 sex- and age-matched control subjects. For the nontarget waveforms, P2 amplitude was reduced in PD patients. For the target waveforms, a topographical difference between female PD patients and female controls was found for N200 amplitude, which attenuated in female PD patients over the parietal area. Two subcomponents of N200, N2a and N2b, were measured from the difference waveforms. A significant group difference was found for N2b amplitude, which reduced in PD patients compared with unaffected control subjects. It is suggested that N2b reduction reflects an abnormally controlled processing of stimulus information in PD.