Epidemiology of panic disorder: progress and unresolved issues

Seizure phobia: A distinct psychiatric disorder among people with epilepsy

OBJECTIVE

Epilepsy is characterized by unpredictable attacks. Hence, people with epilepsy (PWE) may develop anxious anticipation of upcoming seizures. Seizure phobia is an anxiety disorder wherein seizure anticipatory situations trigger fear, accompanied by avoidance behaviors. Research on seizure phobia among PWE is scarce. Therefore, we aimed to describe the diagnosis of seizure phobia and its association with demographic, psychiatric and neurological variables.

METHODS

This is a cross-sectional study of adult PWE in a tertiary epilepsy outpatient clinic. Data were collected from semi-structured interviews, demographic questionnaires and medical records. Patients with and without seizure phobia were compared in terms of sociodemographic, psychiatric, and neurological variables. A logistic regression analysis was performed to identify variables that predicted seizure phobia.

RESULTS

Among 69 PWE included in the study, 19 (27.5%) were diagnosed with seizure phobia. In comparison with PWE without seizure phobia, PWE with seizure phobia were predominantly female (84.2% vs 44.2%, p = 0.005), and had more comorbid anxiety disorders (84.2% vs 34.9%, p = 0.01), past major depressive episode (MDE) (63.2% vs 20.9%, p = 0.003), and post-traumatic stress disorder (26.3% vs 7%, p = 0.05). There was a significant association between seizure phobia and comorbid psychogenic non-epileptic seizures (36.8% vs 11.6%, p = 0.034). However, no significant association was found with epilepsy-related variables. A multivariate logistic regression model indicated anxiety and a past MDE as predictive factors for seizure phobia (R² = 0.43).

CONCLUSION

Seizure phobia is a distinct psychiatric entity among PWE. Further research is required to understand its etiology, risk factors, and potential interventions for these patients.

Panic disorder and subthreshold panic in the UK general population: Epidemiology, comorbidity and functional limitation

Objective

The epidemiology of panic disorder has not been investigated in the past in the UK using a nationally representative sample of the population. The aim of the present paper was to examine the epidemiology, comorbidity and functional impairment of subthreshold panic and panic disorder with or without agoraphobia.

Method

We used data from the 2000 Office for National Statistics Psychiatric Morbidity survey (N = 8580). Panic disorder and agoraphobia were assessed with the Revised Clinical Interview Schedule (CIS-R).

Result

The prevalence of panic disorder with or without agoraphobia was 1.70% (95% confidence interval: 1.41–2.03%). Subthreshold panic was more common. Economic inactivity was consistently associated with all syndromes. The comorbidity pattern of the panic syndromes and the associated functional impairment show that panic-related conditions are important public health problems, even in subthreshold status.

Conclusions

The findings show that efforts to reduce the disability associated with psychiatric disorders should include detection and management of panic disorder.

Effects of repeated treatment with a delta opioid receptor agonist KNT-127 on hyperemotionality in olfactory-bulbectomized rats

We previously demonstrated that a single treatment of a non-peptidic delta opioid receptor agonist, KNT-127, has an antidepressant-like effect in rodents in the forced swim test. Here we evaluated the effect of repeated administration of the potential antidepressant KNT-127 in an olfactory-bulbectomized (OBX) rat model. Male Wistar rats (8-12 weeks old) underwent olfactory bulbectomy. From 14days after surgery each was weighed and administered either KNT-127 (3mgkg^-1/day), the selective serotonin reuptake inhibitor (SSRI) fluoxetine (10mgkg^-1/day), or vehicle, daily for 14 days. Hyperemotionality was measured on days 3, 5, 7, 10, and 14. Repeated administration of KNT-127 significantly decreased total and individual hyperemotionality scores (attack, startle, struggle and fight) over the entire period. Conversely, fluoxetine did not show any significant effect on days 3, 5, 7, or 14 but significantly reduced the total score on day 10. The inhibitory effects of KNT-127 were greater than those of fluoxetine. The KNT-127 and control groups both gained weight, while the fluoxetine group lost weight. Our results suggest that KNT-127 is a potential lead compound for antidepressant therapy, with high efficacy, a relatively rapid onset of therapeutic effect, and without the possible adverse effects of weight loss caused by SSRIs.

Ambient ozone concentration and emergency department visits for panic attacks

The effect of ambient air pollution on panic disorder in the general population has not yet been thoroughly elucidated, although the occurrence of panic disorder in workers exposed to organic solvents has been reported previously. We investigated the association of ambient air pollution with the risk of panic attack-related emergency department visits. Using health insurance claims, we collected data from emergency department visits for panic attacks in Seoul, Republic of Korea (2005-2009). Daily air pollutant concentrations were obtained using automatic monitoring system data. We conducted a time-series study using a generalized additive model with Poisson distribution, which included spline variables (date of visit, daily mean temperature, and relative humidity) and parametric variables (daily mean air pollutant concentration, national holiday, and day of the week). In addition to single lag models (lag1 to lag3), cumulative lag models (lag0-1 to lag0-3) were constructed using moving-average concentrations on the days leading up to the visit. The risk was expressed as relative risk (RR) per one standard deviation of each air pollutant and its 95% confidence interval (95% CI). A total of 2320 emergency department visits for panic attacks were observed during the study period. The adjusted RR of panic attack-related emergency department visits was 1.051 (95% CI, 1.014-1.090) for same-day exposure to ozone. In cumulative models, adjusted RRs were 1.068 (1.029-1.107) in lag0-2 and 1.074 (1.035-1.114) in lag0-3. The ambient ozone concentration was significantly associated with emergency department visits for panic attacks.

Gender-specific association between the COMT Val158Met polymorphism and openness to experience in panic disorder patients

BACKGROUND

Because major depression and panic disorder are both more prevalent among females and since several lines of evidence suggest that genetic factors might influence an individual's vulnerability to panic disorder, gene-gender interactions are being examined in such psychiatric disorders and mental traits. A number of studies have suggested that specific genes, e.g. catechol-O-methyltransferase (COMT), might lead to distinct clinical characteristics of panic disorder.

METHOD

We compared gender-specific personality-related psychological factors of 470 individuals with panic disorder and 458 healthy controls in terms of their COMT Val158Met polymorphism and their scores on the Revised NEO Personality Inventory (NEO PI-R) and State-Trait Anxiety Inventory (STAI) with a 1-way analysis of covariance.

RESULTS

In the male panic disorder patients, the NEO PI-R score for openness to experience was significantly lower in the Met/Met carrier group, whereas there was no such association among the female panic disorder patients or the male or female control groups.

CONCLUSION

The gender-specific effect of the COMT genotype suggests that the COMT Val/Met genotype may influence a personality trait, openness to experience, in males with panic disorder.

Panic disorder and subthreshold panic in the light of comorbidity: a follow-up study

Especially in the presence of agoraphobia and comorbid conditions, panic disorder causes significant impairment in life quality. Although there are several studies about epidemiology and clinical features, subthreshold symptoms and courses of comorbidity have not been studied sufficiently in panic disorder. The current study assessed the courses of panic disorder and subthreshold panic symptoms in consideration of the major and subthreshold comorbid conditions. Patients with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-diagnosed panic disorder were assessed using the panic disorder follow-up questionnaire, Panic and Agoraphobia Scale, Hamilton Depression Rating Scale, and State-Trait Anxiety Inventory. Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders was used to determine comorbidity, and all participants were received to 1-year follow-up. Comorbidity assessment showed that the threshold comorbidity decreased, while the subthreshold comorbidity increased at 1-year follow-up. Panic disorder symptom severity was decreased, but subthreshold panic symptoms continued to be present within the course of the illness. Presence of agoraphobia and duration of disease were significantly related with higher Panic and Agoraphobia Scale scores in the second assessment, and these relationships were independent from the treatment process. Even if the comorbidity and the severity of panic decrease with treatment, subthreshold panic and comorbid symptoms may still resist in panic disorder.

A U-shaped relationship between systolic blood pressure and panic symptoms: the HUNT study

BACKGROUND

Previous studies on the relationship between blood pressure (BP) and psychological morbidity are conflicting. To resolve this confusing picture we examined the hypothesis that there is a non-linear relationship between panic and systolic BP (SBP) and explored the association of generalized anxiety symptoms with SBP. Method We used data from the population-based Nord-Trøndelag health study (HUNT) in which all 92 936 individuals aged ≥20 years residing in one Norwegian county were invited to participate. Panic was assessed using one item from the anxiety subscale of the Hospital Anxiety and Depression Scale (HADS) and generalized anxiety with the remaining six items of this subscale. SBP was the mean of two measurements by an automatic device.

RESULTS

A total of 64 871 respondents had SBP recorded (70%). Both unadjusted (n=61 408) and adjusted analyses provided evidence for a non-linear relationship between panic and SBP, represented by a U-shaped curve with a minimum prevalence of panic at around 140 mmHg. The relationship was strengthened after adjustment for confounders, with the quadratic term significantly associated with panic (p=0.03). Generalized anxiety symptoms were associated only with low SBP.

CONCLUSIONS

The U-shaped relationship between SBP and panic provides a unifying explanation for the separate strands of published literature in this area. The results support the hypothesis that high BP and panic disorder could share brainstem autonomic and serotonergic abnormalities. By contrast, generalized anxiety symptoms were more common only at lower BPs, suggesting that any biological link between panic and high BP does not extend to generalized anxiety.

Long-term Escitalopram Treatment in Korean Patients with Panic Disorder: A Prospective, Naturalistic, Open-label, Multicenter Trial

Objective

Panic disorder is characterized by recurrent panic attacks, persistent concerns about additional attacks, and worry about the implications of the attack or significant changes in behavior related to the attacks. We examined the efficacy of 24-week naturalistic, open-label escitalopram treatment in terms of the response and remission rates and functional disability in 119 adult Korean patients with panic disorder from 6 clinical centers in South Korea.

Methods

Clinical severity and functional impairment were assessed at baseline and at 4, 12, and 24 weeks after the treatment using the Panic Disorder Severity Scale and Sheehan Disability Scale. Ninety-six patients (80.7%) showed a treatment response, and 87 patients (73.1%) had attained remission after 24 weeks of escitalopram treatment.

Results

Continuous improvement in the Panic Disorder Severity Scale and Sheehan Disability Scale scores was found over the 24 weeks of treatment.

Conclusion

These findings suggest that escitalopram treatment is very effective for panic disorder in terms of both response and remission rates and that long-term pharmacotherapy with escitalopram continuously improved panic symptoms and functional disability in Korean patients with panic disorder.

Childhood separation anxiety disorder and adult onset panic attacks share a common genetic diathesis

BACKGROUND

Childhood separation anxiety disorder (SAD) is hypothesized to share etiologic roots with panic disorder. The aim of this study was to estimate the genetic and environmental sources of covariance between childhood SAD and adult onset panic attacks (AOPA), with the primary goal to determine whether these two phenotypes share a common genetic diathesis.

METHODS

Participants included parents and their monozygotic or dizygotic twins (n = 1,437 twin pairs) participating in the Virginia Twin Study of Adolescent Behavioral Development and those twins who later completed the Young Adult Follow-Up (YAFU). The Child and Adolescent Psychiatric Assessment was completed at three waves during childhood/adolescence followed by the Structured Clinical Interview for DSM-III-R at the YAFU. Two separate, bivariate Cholesky models were fit to childhood diagnoses of SAD and overanxious disorder (OAD), respectively, and their relation with AOPA; a trivariate Cholesky model also examined the collective influence of childhood SAD and OAD on AOPA.

RESULTS

In the best-fitting bivariate model, the covariation between SAD and AOPA was accounted for by genetic and unique environmental factors only, with the genetic factor associated with childhood SAD explaining significant variance in AOPA. Environmental risk factors were not significantly shared between SAD and AOPA. By contrast, the genetic factor associated with childhood OAD did not contribute significantly to AOPA. Results of the trivariate Cholesky reaffirmed outcomes of bivariate models.

CONCLUSIONS

These data indicate that childhood SAD and AOPA share a common genetic diathesis that is not observed for childhood OAD, strongly supporting the hypothesis of a specific genetic etiologic link between the two phenotypes.

Determinants of barriers to treatment for anxiety disorders

The objectives of this study were to evaluate perceived unmet need for mental healthcare, determinants of unmet need, and barriers to care in individuals with social anxiety (SA) or panic disorder with agoraphobia (PDA) in Quebec. Data from 206 participants diagnosed with SA or PDA were collected using an online questionnaire. Correlational analyses and binary stepwise logistic regressions were conducted to explore determinants of perceived unmet need. Of the 206 participants, 144 (69.9%) reported instances of unmet need for treatment. Perceived unmet need was correlated with variables related to the severity of the disorder, such as comorbid depression, avoidance, duration of worry, interference with functioning, and time lapsed between the appearance of first symptoms and first consultation. Depression and avoidance emerged as predictors for perceived unmet need in the regression analysis. The most common barriers to treatment reported were concern about the cost of services (63.9%), not knowing where to go to get help (63.2%), lack of health insurance coverage (52.4%), and appointment wait times (52.1%). The results of this study demonstrate the need to overcome barriers to treatment engendered by avoidance behaviors associated with anxiety. Potential methods for achieving this objective include Internet outreach, support groups, and increased accessibility to public services.

The prevalence of panic disorder in pregnant women during the third trimester of pregnancy

OBJECTIVE

The principal aim of this study was to assess the current prevalence rate of panic disorder (PD) in pregnant women during the third trimester of pregnancy. The second aim of the present study was to investigate the clinical characteristics of PD in pregnant and nonpregnant women.

METHOD

The study data were gathered from 512 consecutive women in the third trimester of pregnancy who were admitted to the obstetric outpatient clinics of 2 university research centers. The diagnosis of PD was determined by means of the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Axis I disorders in the third trimester of pregnancy. Within the same period, the Panic and Agoraphobia Scale was used to determine the severity of PD. In addition, we compared the clinical characteristics of PD in gravid subjects (n = 13) with their control group. A control group was composed of 19 consecutive nonpregnant female outpatients diagnosed with PD who presented to the psychiatric outpatient clinics of the same hospitals.

RESULTS

The prevalence rate of PD was found to be 2.5% (n = 13) among the subjects in the third trimester of pregnancy. Of these 13 pregnant, 7 subjects reported that PD developed during the 6th to 28th weeks of their gestation, and the number of subjects who experienced PD symptoms before pregnancy was 6. In addition, there was no statistically difference between gravid and nongravid PD cases with regard to the severity of panic symptoms.

CONCLUSION

Our study suggests that PD may be common among pregnant females during the third trimester of pregnancy and seems to be associated with similar clinical features during gestation and nongestation.

Inter-informant agreement on diagnoses and prevalence estimates of anxiety disorders: direct interview versus family history method

The aims of the present study were to: (1) assess agreement for diagnoses of specific anxiety disorders between direct interviews and the family history method; (2) compare prevalence estimates according to direct interviews and family history information; (3) test strategies to approximate prevalence estimates according to family history reports to those based on direct interviews; (4) test covariates of inter-informant agreement; and (5) test the likelihood of reporting disorders by informants. Analyses were based on family study data which included 1625 distinct informant (first-degree relatives and spouses)-index subject pairs. Our main findings were: (1) inter-informant agreement was satisfactory for panic disorder, agoraphobia, social phobia and obsessive-compulsive disorder; (2) the family history method provided lower prevalence estimates for all anxiety disorders (except for generalized anxiety disorder and obsessive-compulsive disorder) than direct interviews; (3) the lowering of diagnostic thresholds and the combination of multiple family history reports increased the accuracy of prevalence estimates according to the family history method; (4) female gender of index subjects was associated with poor agreement; and (5) informants, who themselves had a history of an anxiety disorder, were more likely to detect this disorder in their relatives which entails the risk of overestimation of the size of familial aggregation.

Course of panic disorder during the early postpartum period: a prospective analysis

PURPOSE

Most of the studies about course of panic disorder (PD) after childbirth have a retrospective nature. The aim of the current study was to examine prospectively the clinical course of 13 pregnant women with a diagnosis of PD across pregnancy and the early postpartum period.

METHOD

The diagnosis of PD was determined by means of the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Axis I Disorders in the third trimester of pregnancy. Within the same period, the Panic and Agoraphobia Scale was used to determine the severity of PD. The last assessment with both instruments was performed at 6 weeks postnatally.

RESULTS

Of these 13 women, 6 (group 1) reported that PD developed during the 6th to the 28th week of their gestation, and the number of women who experienced PD symptoms before pregnancy (group 2) was 7. It was found that the severity of panic symptoms considerably decreased in the total sample, group 1, and group 2 from the basal levels to 6 weeks postnatally.

CONCLUSION

Our study results suggest that pregnant women with PD may experience a marked improvement in PD symptoms in the early postpartum period.

Panic disorder in later life: results from a national survey of Canadians

BACKGROUND

At present, our understanding of the risk markers associated with panic disorder among older, community dwelling older adults is limited. To address this gap, we examined the prevalence, risk markers, and comorbidity of panic disorder defined using DSM-IV criteria among older adults.

METHOD

Using data drawn from a large, nationally representative sample of Canadians, we estimated lifetime and 12-month prevalence of panic disorder, and examined demographic predictors and patterns of comorbidity of current panic disorder in adults aged 55 years and older (n = 12,792).

RESULTS

The 12-month and lifetime prevalence estimates of panic disorder in this sample were 0.82% and 2.45% respectively, and one-fifth of these cases reported a first onset after the age of 55 years. In multivariate models, the risk of panic disorder decreased with older age and was significantly lower among widowed respondents. Physical limitations in daily activities as well as the presence of other psychiatric disorders (major depression, and social phobia) were also significantly associated with panic disorder in this sample.

CONCLUSIONS

Consistent with previous research on panic disorder, the prevalence of the disorder decreased with age among older adults. Potential explanations for the age effect and the clinical implications of the mental health comorbidities with panic disorder are discussed.

Panic comorbidity with bipolar disorder: what is the manic-panic connection?

CONTEXT

Bipolar/panic comorbidity has been observed in clinical, community and familial samples. As both are episodic disorders of affect regulation, the common pathophysiological mechanism is likely to involve deficits in amygdala-mediated, plasticity-dependent emotional conditioning.

EVIDENCE

Neuronal genesis and synaptic remodeling occur in the amygdala; bipolar and panic disorders have both been associated with abnormality in the amygdala and related structures, as well as in molecules that modulate plasticity, such as serotonin, norepinephrine, brain-derived neurotrophic factor (BDNF) and corticotrophin releasing factor (CRF). These biological elements are involved in behavioral conditioning to threat and reward.

MODEL

Panic attacks resemble the normal acute fear response, but are abnormally dissociated from any relevant threat. Abnormal reward-seeking behavior is central to both manic and depressive syndromes. Appetites can be elevated or depressed; satisfaction of a drive may fail to condition future behavior. These dissociations may be the result of deficits in plasticity-dependent processes of conditioning within different amygdala subregions.

CONCLUSIONS

This speculative model may be a useful framework with which to connect molecular, cellular, anatomic and behavioral processes in panic and bipolar disorders. The primary clinical implication is that behavioral treatment may be critical to restore function in some bipolar patients who respond only partially to medications.

The epidemiology of panic attacks, panic disorder, and agoraphobia in the National Comorbidity Survey Replication

CONTEXT

Only limited information exists about the epidemiology of DSM-IV panic attacks (PAs) and panic disorder (PD).

OBJECTIVE

To present nationally representative data about the epidemiology of PAs and PD with or without agoraphobia (AG) on the basis of the US National Comorbidity Survey Replication findings.

DESIGN AND SETTING

Nationally representative face-to-face household survey conducted using the fully structured World Health Organization Composite International Diagnostic Interview.

PARTICIPANTS

English-speaking respondents (N=9282) 18 years or older.

MAIN OUTCOME MEASURES

Respondents who met DSM-IV lifetime criteria for PAs and PD with and without AG.

RESULTS

Lifetime prevalence estimates are 22.7% for isolated panic without AG (PA only), 0.8% for PA with AG without PD (PA-AG), 3.7% for PD without AG (PD only), and 1.1% for PD with AG (PD-AG). Persistence, lifetime number of attacks, and number of years with attacks increase monotonically across these 4 subgroups. All 4 subgroups are significantly comorbid with other lifetime DSM-IV disorders, with the highest odds for PD-AG and the lowest for PA only. Scores on the Panic Disorder Severity Scale are also highest for PD-AG (86.3% moderate or severe) and lowest for PA only (6.7% moderate or severe). Agoraphobia is associated with substantial severity, impairment, and comorbidity. Lifetime treatment is high (from 96.1% for PD-AG to 61.1% for PA only), but 12-month treatment meeting published treatment guidelines is low (from 54.9% for PD-AG to 18.2% for PA only).

CONCLUSION

Although the major societal burden of panic is caused by PD and PA-AG, isolated PAs also have high prevalence and meaningful role impairment.

Is major depressive episode related to anxiety disorders in anorexics and bulimics?

OBJECTIVE

To determine whether the presence of anxiety disorders is related to depressive comorbidity in subjects with eating disorders (ED), while taking into account certain variables that may be related to depression (subjects' age, ED duration, prior incidents of anorexia nervosa in bulimic subjects, inpatient or outpatient status, nutritional state [as measured by body mass index]).

METHOD

We evaluated the frequency of depressive disorders in 271 subjects presenting with a diagnosis of either anorexia nervosa or bulimia, using the Mini International Neuropsychiatric Interview, DSM-IV version.

RESULTS

A multivariate analysis reveals that anxiety disorders do not all have the same influence in terms of risk of onset of major depressive episode in anorexics and bulimics when adjusted on variables related to depression.

CONCLUSION

Depression in subjects with ED can be explained in part by comorbidity with obsessive-compulsive disorder, generalized anxiety, social phobia, and panic disorder.

Prevalence and incidence studies of anxiety disorders: a systematic review of the literature

OBJECTIVE

To present the results of a systematic review of literature published between 1980 and 2004 reporting findings of the prevalence and incidence of anxiety disorders in the general population.

METHOD

A literature search of epidemiologic studies of anxiety disorders was conducted, using Medline and HealthSTAR databases, canvassing English-language publications. Eligible publications were restricted to studies that examined age ranges covering the adult population. A set of predetermined inclusion and exclusion criteria were used to identify relevant studies. Prevalence and incidence data were extracted and analyzed for heterogeneity.

RESULTS

A total of 41 prevalence and 5 incidence studies met eligibility criteria. We found heterogeneity across 1-year and lifetime prevalence rates of all anxiety disorder categories. Pooled 1-year and lifetime prevalence rates for total anxiety disorders were 10.6% and 16.6%. Pooled rates for individual disorders varied widely. Women had generally higher prevalence rates across all anxiety disorder categories, compared with men, but the magnitude of this difference varied.

CONCLUSION

The international prevalence of anxiety disorders varies greatly between published epidemiologic reports. The variability associated with all anxiety disorders is considerably smaller than the variability associated with individual disorders. Women report higher rates of anxiety disorders than men. Several factors were found to be associated with heterogeneity among rates, including diagnostic criteria, diagnostic instrument, sample size, country studied, and response rate.

Anxiety disorders in women: does gender matter to treatment?

Women have a substantially higher risk of developing lifetime anxiety disorders compared with men. In addition, research evidence has generally observed an increased symptom severity, chronic course, and functional impairment in women with anxiety disorders in comparison to men. However, the reasons for the increased risk in developing an anxiety disorder in women are still unknown and have yet to be adequately investigated. Evidence from various studies has suggested that genetic factors and female reproductive hormones may play important roles in the expression of these gender differences. The significant differences in onset and course of illness observed in men and women diagnosed with anxiety disorders warrants investigations into the need of differential treatment; however, evidence of gender differences in treatment response to different anxiety disorders are varying and remain largely inconclusive. This article reviews the prevalence, epidemiology, and phenomenology of the major anxiety disorders in women, as well as the implications of such differences for treatment.

L’existence d’un épisode dépressif majeur est-elle liée à la présence de troubles anxieux chez les anorexiques et les boulimiques ?

The primaty objective is to determine whether the presence anxiety disorders is related to depressive comorbidity in subjects suffering from ED, while taking into account certain variables which may be related to depression [subjects' age, ED duration, prior incidents of anorexia nervosa in BN subjects, inpatient or outpatient status, nutritional state (as measured by Body Mass Index or BMI)]. Our secondary objective is to evaluate the relative chronology of the onset of anxiety disorders and depressive disorders in anorexic and bulimic subjects.

METHOD

We evaluated the frequency of depressive disorders in 271 subjects presenting with a diagnosis of either anorexia nervosa or bulimia, using the Mini International Neuropsychiatric Interview (MINI), DSM IV version.

RESULTS

While univariate analyses show that nearly all anxiety disorders are related to major depressive episode (MDE), a separate analysis of each anxiety disorder reveals that they do not all have the same influence in terms of risk of onset of MDE in anorexics and bulimics, when adjusted for univariate variables related to MDE (subjects' age, ED duration, prior incidents of anorexia nervosa in BN subjects, inpatient or outpatient status, nutritional state). Current generalized anxiety is significantly related to lifetime presence of MDE in AN subjects, and to current MDE in AN and BN subjects. Generalized anxiety is the most frequent disorder in AN and BN subjects to according our study; it also appears to be one of the principal predictive factors for MDE, which is 2.4 to 4.2 times more frequent when GAD is present. Diagnosis of OCD has its own particular effect on lifetime risk for MDE in AN subjects, regardless of GAD: it increases the risk of depression by 3.5. It is one of the most frequent anxiety disorders among AN subjects, present in nearly a quarter of them. In bulimics, when GAD is excluded, two factors are related to current diagnosis of MDE: panic disorder and subjects' inpatient or outpatient status. Hospitalized bulimics are diagnosed with current MDE 4.4 times more often than those seen as.

Association study of A2a adenosine receptor genetic polymorphism in panic disorder

The adenosine A2a receptor (A2aAR) is thought to be implicated in the pathogenesis of panic disorder because caffeine, a potent antagonist for A2aAR, can precipitate panic attacks, and because disruption of the A2aAR gene increased anxiety-behaviors in mice. Recent studies demonstrated that the A2aAR 1976T > C genetic variant confers susceptibility to panic disorder though not by all studies. The present study tested the hypothesis that the A2aAR 1976T > C genetic variant confers susceptibility to panic disorder using a Chinese population of 104 panic disorder patients and 192 normal controls. We also tested whether the A2aAR 1976T > C polymorphism relates to the age of onset or subtype of panic disorders. Neither the distribution of the A2aAR 1976T > C genotypes (P = 0.296) or alleles (P = 0.864), nor the age of onset (P = 0.719) were significantly different among genotype groups. Furthermore, no association was demonstrated between this A2aAR polymorphism and either mitral-valve prolapse or agoraphobia in panic-disorder patients. These findings suggested that it is unlikely that the A2aAR 1976T > C polymorphism plays a major role in panic disorder pathogenesis in the Chinese population. The positive association between this polymorphism and panic disorder found in western population but not in Asian population suggests that this association could be ethnicity-dependent. The 1976C > T polymorphism may be in linkage disequilibrium with a functional variant that affects panic disorder, and the extent of this linkage disequilibrium is not similar for all ethnic populations.

Gender differences in anxiety-related traits in patients with panic disorder

This study examined gender differences in anxiety-related personality traits in patients with panic disorder with or without agoraphobia (PD+/-AG). Outpatients (101 total) with SCID confirmed PD+/-AG completed the Anxiety Sensitivity Index (ASI), the Trait form of the State-Trait Anxiety Inventory (STAI-T), the NEO Personality Inventory Revised (NEO PI-R), and the Retrospective Self-Report of Inhibition (RSRI) as part of their assessment. Significant gender differences were not detected for the total ASI scores. Females scored significantly higher than males on the Physical Concerns subscale of the ASI, whereas males scored significantly higher than women on the Social Concerns subscale. Women scored higher than men on the Extraversion scale of the NEO PI-R as well as on certain subscales of this domain. Although a significant gender difference was not detected on the Neuroticism subscale, men scored higher on the angry hostility and depression facets of this trait. Significant gender differences were not found for the STAI-T or the RSRI. These findings suggest that gender differences exist among patients with PD+/-AG in the feared consequences of anxiety symptoms as well as in the personality characteristics of extraversion.

Sensitivity to carbon dioxide in subjects with a single lifetime panic attack: possible clinical "bedside" predictive test for panic disorder after a first attack

There is currently no way of knowing whether a patient who has recently had a single panic attack has incipient panic disorder. Sensitivity to carbon dioxide (CO2) is lower in healthy volunteers than in panic disorder patients. If this is also true of people who experience a single lifetime panic attack, it could be used as a prognostic test. Subjects with a single lifetime panic attack and subjects with panic disorder received an inhalation of 35% CO2. Subjects completed the panic symptoms scale (PSS), and also stated whether they considered that they had experienced an attack. None of 14 subjects with a single lifetime panic attack, compared to 7 of 17 subjects with panic disorder (P=.009), had an attack. The PSS also distinguished between the groups. The 35% CO2 challenge warrants further investigation as a predictive test after a first panic attack.

Conditioning and residual emotionality effects of predator stimuli: some reflections on stress and emotion

The advantages of using predator-related odor stimuli to study emotional responses in laboratory tests depend on whether such stimuli do elicit a relatively complete pattern of emotionality. This has been confirmed for cat fur/skin odor stimuli, which elicit a range of defensive behaviors in rats that may be reduced by anxiolytic drugs, produce residual anxiety-like behavior in the elevated plus maze and support rapid aversive conditioning to the context in which they were encountered. Although the synthetic fox fecal odor, trimethylthiazoline (TMT), elicits avoidance similar to that seen in response to cat fur/skin odor, this avoidance does not respond to anxiolytic drugs. In addition, TMT does not produce residual anxiety-like behaviors in the elevated plus maze, nor does it support conditioning. As natural cat feces also elicit avoidance but fail to support conditioning, it is possible that the ability of a predator-related odor to serve as an effective unconditioned stimulus (US) relates to its predictive status with reference to the actual presence of the predator. Avoidance per se may reflect that a stimulus is aversive but not necessarily capable of eliciting an emotional response. This view is consonant with findings in a Mouse Defense Test Battery (MDTB) measuring a wide range of defensive responses to predator exposure. A contextual defense measure that may reflect either conditioned or residual but unconditioned emotional responses was almost never reduced by drug effects unless these also reduced risk assessment or defensive threat/attack measures. However, reductions in contextual defense without changes in flight/avoidance measures were much more common. These findings suggest that flight/avoidance, although it obviously may occur as one component of a full pattern of defensive and emotional behaviors, is also somewhat separable from the others. When-as appears to be the case with TMT-it is the major or perhaps only consistent defensive behavior elicited, this may reflect a stimulus that is aversive or noxious but with little ability to predict the presence of threat or danger. That such stimuli fail to support rapid aversive conditioning suggests the need for a reanalysis of the characteristics required for an effective aversive US.

Evaluation of the effects of chronic mild stressors on hedonic and physiological responses: sex and strain compared

The chronic mild stress (CMS) paradigm was developed in order to simulate in animals the symptom of anhedonia, a major feature of depression. Typically, changes in hedonic status are interpreted from a decrease in either intake or preference for a mild sucrose solution. Although the incidence of clinical depression is significantly higher in women than in men, the study of this disorder in most animal models of depression has been based on the responses of male rodents. The purpose of this study was to compare the effects of 6 weeks of CMS administration among male and female rats of two rat strains, Sprague-Dawley (SD) and Long Evans (LE), with respect to physiological (body, adrenal gland, and spleen weight) and biochemical (plasma corticosterone levels) indices of stress as well as evaluations of 1 and 24 h sucrose intake and preference. Estrous cycle was tracked throughout the study. Overall, our results indicate a slower rate of weight gain in animals, greater in males, exposed to the chronic stressor regime. Furthermore, CMS is shown to disrupt estrous cycling, predominantly in the Long Evans strain of rats. The main behavioral finding was a significant reduction in 24 h sucrose intake in female treated groups, which was not accompanied by alterations in preference. Corticosterone levels were elevated in CMS-treated animals relative to the singly housed control groups, but exposure to a subsequent stressor was not influenced by the stress history. Taken together, the effects of chronic stressor exposure are evident, based on physiological and biochemical indices, although none of the measures distinguished any striking gender specific reactions. The usefulness of sucrose intake or preference as behavioral indices of CMS-induced anhedonia in males and females is modest at best.

Anxiety disorders in women

Women have higher overall prevalence rates for anxiety disorders than men. Women are also much more likely than men to meet lifetime criteria for each of the specific anxiety disorders: generalized anxiety disorder (GAD), obsessive-compulsive disorder (OCD), social anxiety disorder (SAD), posttraumatic stress disorder (PTSD), simple phobia, panic disorder, and agoraphobia. Considerable evidence suggests that anxiety disorders remain underrecognized and undertreated despite their association with increased morbidity and severe functional impairment. Increasing evidence suggests that the onset, presentation, clinical course, and treatment response of anxiety disorders in women are often distinct from that associated with men. In addition, female reproductive hormone cycle events appear to have a significant influence on anxiety disorder onset, course, and risk of comorbid conditions throughout a woman's life. Further investigations concerning the unique features present in women with anxiety disorders are needed and may represent the best strategy to increase identification and optimize treatment interventions for women afflicted with these long-neglected psychiatric disorders.

Quality of life in anxiety disorders: a comparison of obsessive-compulsive disorder, social anxiety disorder, and panic disorder

BACKGROUND

There is growing recognition that the anxiety disorders are disabling disorders associated with substantial morbidity and impaired quality of life (QOL). Nevertheless, there have been few studies comparing QOL across these conditions.

SAMPLING AND METHODS

337 outpatients with obsessive-compulsive disorder (OCD; n = 220), panic disorder (PD; n = 53), or social anxiety disorder (SAD; n = 64) were compared using a number of assessment scales to compare objective and subjective impairment in QOL. The association of QOL with symptom severity and comorbid depression was also assessed.

RESULTS

The extent of impairment due to OCD, PD or SAD appears to be similar across the QOL scales. However, various domains are differentially affected in each of the disorders; OCD patients had more impairment in family life and activities of daily living; SAD patients had more impairment in social life and leisure activities, and PD patients were less able to avoid the use of nonprescribed drugs. QOL was lower in patients with increased symptom severity as well as in those with comorbid depression.

CONCLUSIONS

While the extent of impairment appears similar across a number of different anxiety disorders, characteristic symptoms of each disorder may be associated with differential impairment of various domains of function, and may require specifically tailored interventions.

Marital relationship and the treatment of panic disorder with agoraphobia: a critical review

The purpose of this paper is (1) to specify, among studies on the links between marital relationship and cognitive-behavioral treatment of panic disorder with agoraphobia (PDA), the conceptual and methodological limitations that may have produced inconsistent results in this field so far; and (2) to propose avenues of research that will help in remedying current weaknesses and answering important questions in this area. Following definition of PDA and a survey of its socioeconomic consequences, the authors examine results of the various ways research has tried to specify the links between marital relationship and the development, maintenance, and treatment of this disorder: the study of major life events before and after the onset of PDA, interpersonal problems and quality of marital relationship in the presence of PDA, the links between marital relationship and PDA treatment outcome, variability of experimental outcomes according to types of measure used to study these links, the effect of the spouse as co-therapist in PDA treatment, and the impact of a PDA treatment based on marital communication and problem-solving. Research hypotheses and methodological procedures are proposed to improve understanding of PDA and its treatment outcome.

Central and peripheral chemoreflexes in panic disorder

Klein (Arch Gen Psychiatry, 50, 1993, 306-317) has suggested that panic disorder patients have a false suffocation alarm that may be associated with a lowered threshold for carbon dioxide detection. We compared the thresholds and sensitivities of the central and peripheral chemoreflexes between panic disorder patients and age- and sex-matched healthy volunteers to test this aspect of the hypothesis. We used a modified version of Read's rebreathing technique in 11 panic disorder patients and 10 healthy volunteers to examine the peripheral and central chemoreflex characteristics in these two populations. Subjects were examined during three rebreathing tests: training, hyperoxic (central chemoreflex alone) and hypoxic (combined central and peripheral chemoreflex). Panic symptoms were retrospectively assessed between groups using a DSM-IV derived Panic Symptom Scale. Comparisons of panic disorder patients with agoraphobia and healthy volunteers showed no significant differences in sensitivities or thresholds. Klein's hypothesis is not supported by these data. If a false suffocation alarm exists, its triggering may not be implemented within the respiratory chemoreflexes.

Effects of tryptophan depletion on central and peripheral chemoreflexes in man

Klein (Arch. Gen. Psychiatry 50, 306-317, 1993) suggests that panic attacks are the result of a defective 'suffocation alarm' threshold that presents with carbon dioxide (CO(2)) hypersensitivity, exaggerated ventilatory response and panic in panic disorder (PD) patients. Serotonergic deficiencies enhance this ventilatory response in PD patients, as per 'suffocation alarm' theory predictions, suggesting that serotonin (5-HT) normalizes the ventilatory response. Other research supports a serotonin system-mediated stimulation of ventilation. Knowledge of 5-HT's role on ventilatory output and its neurophysiological sources impacts on the 'suffocation alarm' theory validity and predictive value. We used tryptophan depletion (TRP-) in concert with a modified Read rebreathing test to determine the effect of deficient serotonergic modulation on the central and peripheral chemoreflex threshold and sensitivity of response to CO(2) in 11 healthy men. TRP- did not affect central or peripheral chemoreflex threshold or sensitivity of response to CO(2). However, basal ventilation was significantly elevated during TRP-. In contrast to 'suffocation alarm' theory predictions, decreased 5-HT neurotransmission does not significantly affect the respiratory chemoreflex response to CO(2), impacting on non-chemoreflex drives to breathe. Panic associated respiratory abnormalities may be related to defective 5-HT modulation of non-chemoreflex drives to breathe, unrelated to any respiratory chemoreflex abnormality.

Relationship between perfectionism, personality disorders and agoraphobia in patients with panic disorder

OBJECTIVE

In earlier reports, we found that perfectionism might be involved in the development and/or maintenance of agoraphobia in panic disorder. The present report extends this work by examining the relationship between perfectionism and comorbidity with personality disorders in panic disorder patients with agoraphobia (PDA) and those without agoraphobia (PD).

METHOD

We examined comorbidity of personality disorders by Structured Clinical Interview for DSM-III-R Personality Disorders (SCID-II) and assessed perfectionism using multidimensional perfectionism scale in 56 PDA and 42 PD patients.

RESULTS

The PDA group met criteria for at least one personality disorder significantly more often than the PD group. With stepwise regression analyses, avoidant and obsessive-compulsive personality disorders emerged as significant indicators of perfectionism in patients with panic disorder.

CONCLUSION

These findings suggest that perfectionism in panic disorder patients may be more common in those with comorbid personality disorders, and may be an important target for preventive and therapeutic efforts.

Panic attack as a marker of core psychopathological processes

OBJECTIVE

The goal of this study is to test the hypothesis that panic attacks are a marker of core psychopathological processes across mental disorders and that there are distinct syndromal patterns of psychopathology associated with specific subtypes of panic attack that can be distinguished by age and associated fear at onset.

METHODS

Data were drawn from the National Comorbidity Survey, a community-based household sample (n = 8,098) representative of the United States adult population. Four panic subtypes were identified based on findings from clinical studies and on our hypothesis. Multivariate logistic regression models were used to identify sociodemographic characteristics, panic symptoms and mental disorder correlates of each subtype.

RESULTS

Results of multivariate logistic regression analyses identified distinct sociodemographic characteristics, panic symptoms, psychiatric comorbidity, suicidal behavior and use of services associated with early-onset and late-onset panic with and without fear/anticipatory anxiety at the first attack.

CONCLUSIONS

These findings provide support for the hypothesis that panic attacks are a marker of core underlying psychopathological processes and introduce new, preliminary evidence to support the possible existence of different panic subtypes in the general population. While these results need replication, these findings suggest that the specific type of comorbidity among those with panic attacks can be predicted to a large degree by the age and associated fear/anticipatory anxiety at the onset of the panic attacks.

Antipsychotic drugs for non-psychotic patients: assessment of the benefit/risk ratio in generalized anxiety disorder

Antipsychotic drugs (neuroleptics, major tranquillizers) are frequently prescribed for the relief of anxiety symptoms. A recent survey of a representative sample of psychiatrists found that these drugs are often given to patients who are not suffering from psychotic disorders, a practice that also appears to be common among general practitioners. Many authors have commented on the value of antipsychotics in relieving anxiety symptoms, both in the short and long term, as an alternative to benzodiazepines (with their associated risk of possible tolerance and dependence), although few recent papers recommend their use in this respect. This paper summarizes the evidence from treatment studies of antipsychotic drugs in patients with generalized anxiety disorder (GAD), and compares this with the advice given in major psychiatric textbooks. Most of the studies identified on the use of antipsychotic drugs in GADs appear to have major methodological flaws, and no study has considered the benefit/risk ratio carefully.

Clinical features in panic disorder with agoraphobia: a comparison of men and women

This study compared 96 women and 58 men suffering from panic disorder with agoraphobia. Participants completed questionnaires assessing various clinical features associated with panic disorder with agoraphobia (PDA), general adjustment, and drug/alcohol use. Results showed that PDA is a more severe condition in women. Women reported more severe agoraphobic avoidance when facing situations or places alone, more catastrophic thoughts, more body sensations, and higher scores on the Fear Survey Schedule. Also, women more often had a comorbid social phobia or posttraumatic stress disorder. The lower agoraphobic avoidance of men was associated with their alcohol use. However, there were no differences between genders in other dimensions, including depression, situational and trait anxiety, stressful life events, social self-esteem, marital adjustment, and drug use.

Panic disorder: the ultimate anxiety

Panic disorder, an intense exacerbation of anxiety accompanied by a variety of physical symptoms, is twice as common among women as among men. Onset is bimodal (teens/20 s and mid-30 s/40 s), 50% of cases are accompanied by agoraphobia, and the etiology is probably multifactorial. Treatment in the primary care setting includes pharmacologic (selective serotonin reuptake inhibitors) and cognitive-behavioral intervention. Medication is initiated at low doses, and the drug-evaluation trial is of 6 weeks duration. Psychiatric referral is helpful in nonresponders and in those with comorbid psychiatric conditions. Outcome varies, with most patients experiencing relief with treatment. For some people, however, the disorder is chronic, with ongoing exacerbations and remissions.

Treatment-outcome research in panic disorder: dilemmas in reconciling the demands of pharmacological and psychological methodologies

Panic disorder with or without agoraphobia has been the subject of sustained treatment-outcome research. Studies have been conducted by both pharmacologically- and psychologically-oriented researchers each employing their own methodologies. Problems arise in attempting to reconcile the demands of these two treatment-outcome methodologies, whilst at the same time ensuring that research designs reflect the reality of wider clinical practice. In the following discussion a series of studies comparing pharmacological and psychological treatments for panic disorder and agoraphobia are reviewed. The review highlights areas where the competing demands of research design and clinical applicability lead to dilemmas for the researcher. Attempts to overcome such dilemmas are described and alternative solutions discussed.

Panic disorder: a theoretical synthesis of medical and psychological approaches

Panic disorder is a common and disabling condition which frequently leads to excessive reliance upon medical facilities. It is also closely associated with the development of agoraphobia. Medical approaches implicate disturbances of ascending brain noradrenergic and serotonergic systems, and support related pharmacotherapies. Contemporary psychological approaches focus upon misinterpretations of bodily sensations and an undue appreciation of the risk of life-threatening illness, and support cognitive/behavioral psychotherapies. A synthesis is possible by developing the view that the implicated ascending aminergic systems normally play a part in "effortful" or context-sensitive behavior. A relative failure of this under conditions of heightened arousal might be responsible for the rigid patterns of fear, belief, and behavior that characterize these patients. Clinical and research implications are discussed.

Asthma and panic attacks

Panic disorder (PD) and asthma share many common characteristics and have been found in epidemiological studies to be significantly comorbid. To investigate possible reasons for this overlapping, the authors evaluated 51 patients with asthma, assessing the prevalence of PD and sporadic panic attacks, the temporal relationship between these two disorders, and the familial risk for PD in the families of asthmatics. The results showed significantly higher prevalences of PD, sporadic panic attacks, and social phobia in asthmatics than those reported for the general population. In 9 (90%) of the asthmatics with PD, asthma appeared first. Finally, the morbidity risk for PD in families of asthmatics with PD (13.5%) was significantly higher than in families of asthmatics without evidence of panic (2%). Our results suggest that the high prevalence of PD in asthmatics might be related to a facilitating effect of asthma on the development of PD in subjects with familial predisposition to PD.

Panic disorder, anxiety and depression in resistant hypertension--a case-control study

BACKGROUND

It has been suggested that panic disorder can cause or contribute to hypertension or resistance to antihypertensive drugs.

OBJECTIVE

To compare the prevalences of panic disorder, panic attacks, anxiety and depression between patients with resistant hypertension and age- and sex-matched patients with non-resistant hypertension.

DESIGN

A case-control study of patients attending the Sheffield Hypertension Clinic, using self-completed postal questionnaires to assess panic disorder, anxiety and depression. PATIENTS CASES: With resistant hypertension were defined as patients who presently or previously had systolic blood pressure above 160 mmHg or diastolic blood pressure above 90 mmHg despite the use of three or more antihypertensive agents at full dose. For each of 136 cases, one control with non-resistant hypertension, defined as controlled to < or = 160/90 mmHg by one or two antihypertensive agents, was identified by a bias-free method. Cases and controls were matched for age and sex.

MAIN OUTCOME MEASURES

Lifetime and current prevalence of panic attacks, the prevalences of panic disorder, anxiety and depression by Hospital Anxiety and Depression Scale scores, and the severity and frequency of panic attacks.

RESULTS

Of the resistant hypertensive patients, 33% had experienced a panic attack compared with 39% of the control non-resistant hypertensives (resistant-non-resistant -6%, 95% confidence interval -19 to +7%). Twelve per cent of the resistant patients and 14% of controls fulfilled the criteria for a current or previous diagnosis of panic disorder (resistant-non-resistant -2%, 95% confidence interval -11% to +7%). There were also no significant differences between the groups in the prevalences of current panic attacks, panic attacks rated as moderate or worse, spontaneous panic attacks and in the frequency of panic attacks. There remained no significant difference between the groups for panic attacks and panic disorder when the analysis was limited to those patients who had idiopathic hypertension. The two groups did not differ significantly in scores for anxiety and depression measured by the Hospital Anxiety and Depression Scale.

CONCLUSION

We observed no differences in the prevalences of panic, anxiety and depression between patients with resistant hypertension and non-resistant controls. These factors are probably not implicated in resistance to drug treatment. However, the prevalences of panic disorder and panic attacks were remarkably high in both groups of patients attending a hospital hypertension clinic. The relationship between panic disorder and hypertension deserves further study in a general hypertensive population.

Use of health services for anxiety disorders: a multisite study in Quebec

OBJECTIVE

We investigated patient characteristics and use of services for anxiety disorders among patients seeking care from participating clinicians at 7 anxiety clinics in Quebec: 3 general hospital clinics, 3 psychologist-run clinics, and one psychiatric hospital clinic.

METHODS

Persons eligible for the study were those who were visiting the clinics for the first time, had a current diagnosis of an anxiety disorder, and could communicate in French or English. Subjects recruited through advertisements were excluded. Data, collected by a self-administered questionnaire, included demographics, treatment history, use of services for anxiety, and the Beck Anxiety Inventory (BAI).

RESULTS

The sample comprised 235 subjects: 146 seen at 3 general hospital clinics, 54 at 3 psychologist-run clinics, and 35 at a psychiatric hospital clinic. There were statistically significant differences by clinic type in the prevalence of specific anxiety diagnoses, BAI score, referral source, antidepressant use, and use of services. High-intensity use (10 or more consultations during the previous year) was reported by 23.4% of the sample for medical services and 19.6% for mental health services. Multiple logistic regression identified variables associated with high-intensity use of medical services (higher BAI score, 1 to 4 years since first sought treatment, and less than 12 years of education) and high-intensity use of mental health services (clinic type, obsessive-compulsive disorder [OCD], and 5 or more years since first sought treatment).

CONCLUSIONS

The patient populations seen at different types of anxiety clinics differ in several respects, including referral source, previous treatment, and severity of symptoms. Regardless of type of clinic, patients with a longer time since they first sought treatment use more services, particularly mental health services. Those with less education use more medical services than those with greater education.

Age and remission of psychiatric disorders

OBJECTIVE

To examine the relationship between remission of psychiatric disorders and age.

METHODS

We interviewed 3258 randomly selected adult residents of Edmonton using the Diagnostic Interview Schedule (DIS), which yielded DIS/DSM-III diagnoses. Remission was defined as being free of symptoms of the index lifetime disorder in the year preceding the interview, this being the difference between the lifetime and one-year prevalence. For each age group, the proportion of cases with and without symptoms in the preceding year was calculated. Numbers and proportions of cases were estimated after adjusting to the census population and weighting for household size. Only the more common disorders were examined; any comorbidities were ignored.

RESULTS

Drug abuse or dependence, antisocial personality disorder (in both sexes), and alcohol abuse or dependence (in men) all showed remission rates that increased with age. Panic disorder and obsessive-compulsive disorder (OCD) showed a decreased likelihood of remission with increasing age. Major depression and phobias showed little tendency to remission with age. Considering all disorders together, the one-year remission rate for all ages combined was only 33.2%, with a tendency for lower remission rates to be found in those aged 55 to 64.

CONCLUSIONS

As may be expected, antisocial personality, drug abuse or dependence, and alcohol abuse or dependence tend to show increased remission rates with increasing age. In OCD and panic disorder, the low rates of remission found in all age groups indicate that these disorders produce significant long-term morbidity. For depression, which had an overall remission rate of less than 50%, the stable low rate of remission probably indicates not only the difficulties of treatment but also the low rates at which cases get treated.

Physiological, biochemical and subjective parameters in anxiety patients with panic disorder during stress exposure as compared with healthy controls

Physiological (heart rate, blood pressure, electrodermal activity), biochemical (epinephrine, norepinephrine, cortisol) and subjective parameters (self-rating score) of 33 patients with panic disorder (diagnoses according to DSM-III-R) before, during and after stress exposure were compared with those of healthy controls. As stressors a video containing frightening scenes (FS), mental arithmetic (MA), a video documenting a patient suffering from a panic attack (PA) and an improvised speech (IS) were applied. We found significantly higher baseline levels of electrodermal activity (EDA) and norepinephrine (NE) secretion and a subsequent further increase during stress exposure in panic disorder patients as compared with normal controls. The most potent stressors during the trial proved to be mental arithmetics and improvised speech, which was evident in both groups. The situation panic attack video appeared to be a "panic disorder patient-specific" stressor; here we noticed the most pronounced reactions in the patient group. Panic disorder patients had significantly higher self-rating scores of the parameters panicky feelings, anxiety and nervousness at the beginning and throughout the investigation. We conclude that panic disorder patients have a higher degree of activation compared with normal controls, which is evident regarding levels of electrodermal activity and norepinephrine secretion. Furthermore, the panic attack video appears to be a panic disorder patient-specific stressor.

Why Is Panic Disorder Less Frequent in Late life?

Epidemiological studies have found that few cases of panic disorder arise for the first time after the age of 40 years, and there is a steady decline in the prevalence of existing cases in the latter half of life. The authors review these epidemiological findings and explore various hypotheses that might explain the decreased frequency of panic disorder in old age. There is no available evidence to suggest that methodological factors have led to an underestimation of the prevalence of this disorder in older rather than younger age groups. However, there is evidence that disorder-associated mortality and age-related changes in brain neurochemistry may contribute to the decreased frequency of this illness in later life. A cohort effect also should be considered, although currently there are no data available to support or refute this idea.