Sensitivity to seasonal changes in panic disorder patients

It has been suggested that symptoms of panic disorder may be significantly affected by seasonal factors including weather changes, although few studies have explored the issue. The purpose of the present paper was to investigate clinical data to examine sensitivity of panic disorder patients to seasonal changes and seasonal fluctuation of panic disorder symptoms. A self-rating questionnaire consisting of the Seasonal Pattern Assessment Questionnaire (SPAQ) and additional self-rating questions were analyzed in 146 Japanese patients (50 male, 96 female) with panic disorder (DSM-IV) at an outpatient clinic for anxiety disorder. The average of the Global Seasonality Scores (GSS) was 12.5+/-4.7 and 25.3% of the patients were suggested to suffer from seasonal affective disorder, according to the GSS. Frequency of the panic attack was found to fluctuate seasonally, with peaks in August and December (P=0.005 and 0.01, chi2 test). The present results indicate that panic disorder patients may be more sensitive to seasonal and meteorological factors than the general population and become more fragile in a specific season or months. This might assist in the development of preventive measures for the frequent recurrence of symptoms in panic disorder.     

Cholecystokinin-tetrapeptide induces panic attacks in patients with panic disorder

Cholecystokinin-tetrapeptide (CCK-4) and placebo were injected to 11 panic disorder patients. CCK-4 induced a panic attack identical to spontaneous panic attacks in all patients; placebo did not induce any attacks. The role of CCK-4 in anxiety disorders is discussed.     

Sleep complaints in panic disorder patients

Patients with anxiety disorders often report difficulty sleeping. The present study assesses the prevalence of sleep complaints in panic disorder (PD) patients, compares them with sleep complaints in a normal population, and investigates the role of comorbid depression and nocturnal panic attacks in sleep complaints in the PD patients. Seventy PD patients and 70 healthy controls were asked about their subjective sleep characteristics by means of the Sleep-Wake Experience List, which assesses sleep/arousal complaints over a 24-hour period. Sixty-seven percent of the PD patients reported sleep complaints, compared with 20% of the controls. Eighty-six percent of the depressed PD patients and 59% of the nondepressed had sleep difficulties; 77% of the PD patients with nocturnal panic attacks reported sleep complaints, versus 53% of the PD patients without nocturnal panic. It is concluded that PD patients demonstrate a higher prevalence of sleep complaints than normal controls; this can only partly be explained by comorbid depression, and cannot be explained by the presence of nocturnal panic attacks.     

Growth hormone response to clonidine in panic disorder patients

The growth hormone (GH) response to clonidine administration (2 micrograms/kg) was compared in three groups of subjects: seven panic disorder patients, seven depressed patients matched for age and sex, and seven normal controls. As previously reported, patients with affective disorders show a blunted GH response to clonidine. Only one panic disorder patient had a blunted GH response to clonidine, and this patient had recently received a tricyclic antidepressant.     

Cytokine production in panic disorder patients

Based on findings that stress and anxiety may modulate immune function, we compared the production of interleukin-2 (IL-2) and interleukin-3 (IL-3) by peripheral blood mononuclear cells between 24 patients with nonmajor depressed panic disorders, 9 with agoraphobia and 15 without, and 19 healthy volunteers. No differences in the production of these cytokines was noted between the patients with panic disorders and the volunteers or between the patients with and without agoraphobia. However, in the patients, a negative correlation was found for interleukin-3 production with severity of state anxiety, but not with trait anxiety or depression. This finding indicates that interleukin-3 levels may be sensitive to the presence of anxiety and stress.     

Prolactin response to TRH in patients with panic disorder

The effects of TRH administration (400 microg, i.v.) on the release of prolactin were examined in 15 patients who met DSM-III-R criteria for panic disorder and 15 normal control subjects. Four hundred micrograms TRH was given via IV route. Blood samples were taken before TRH administration (baseline values) and at 15, 30 and 60 min. The results demonstrate that prolactin responses to TRH did not differ between panic disorder patients and normal control subjects. When only women were evaluated, the findings indicate that women with PD tend to show excessive prolactin responses to TRH. The findings are discussed in view of findings from earlier reports.     

Responses to voluntary hyperventilation in children with separation anxiety disorder: Implications for the link to panic disorder

BackgroundBiological theories on respiratory regulation have linked separation anxiety disorder (SAD) to panic disorder (PD). We tested if SAD children show similarly increased anxious and psychophysiological responding to voluntary hyperventilation and compromised recovery thereafter as has been observed in PD patients.MethodsParticipants were 49 children (5–14 years old) with SAD, 21 clinical controls with other anxiety disorders, and 39 healthy controls. We assessed cardiac sympathetic and parasympathetic, respiratory (including pCO₂), electrodermal, electromyographic, and self-report variables during baseline, paced hyperventilation, and recovery.ResultsSAD children did not react with increased anxiety or panic symptoms and did not show signs of slowed recovery. However, during hyperventilation they exhibited elevated reactivity in respiratory variability, heart rate, and musculus corrugator supercilii activity indicating difficulty with respiratory regulation.ConclusionsReactions to hyperventilation are much less pronounced in children with SAD than in PD patients. SAD children showed voluntary breathing regulation deficits.     

Therapeutic response to phenelzine in patients with panic disorder and agoraphobia with panic attacks

The therapeutic response to phenelzine sulfate was evaluated during 6 months' treatment of 35 outpatients meeting DSM-III criteria for panic disorder or agoraphobia with panic attacks. The possible influence of nonspecific predictors of drug efficacy and some biochemical parameters were investigated. Therapeutic response was assessed on standardized rating scales. Agoraphobic patients showed a significantly higher frequency of panic attacks when compared to the subjects with uncomplicated panic disorder. Phenelzine treatment blocked panic attacks in 100% of the patients with panic disorder and in 94.7% of the agoraphobics. Anticipatory anxiety and avoidant behavior improved markedly, although not statistically significantly, in 73.6% of the agoraphobics.     

Nonfearful panic disorder in neurology patients validated by lactate challenge

OBJECTIVE: Nonfearful panic disorder meets the DSM-III-R criteria for panic disorder but is not associated with subjective fear and anxiety. The authors determined its prevalence in a group of neurology patients and assessed its diagnostic validity as a panic disorder subtype by evaluating the response of the patients with nonfearful panic disorder to sodium lactate and antipanic pharmacotherapy. METHOD: The subjects were all neurology patients referred over 1 year to a university hospital's psychiatric consultation service because of negative medical workups for their symptoms (N = 48). Patients who met the DSM-III-R criteria for panic disorder but did not report subjective anxiety or fear during panic episodes were diagnosed as having nonfearful panic disorder. Afterward, each of those patients received a sodium lactate infusion and, 5 hours later, a sodium chloride infusion. They were then treated with antipanic medication and followed for at least 6 months. RESULTS: Of the 48 neurology patients referred for psychiatric evaluation, 11 (23%) met the criteria for panic disorder, and all 11 met the criteria for nonfearful panic disorder. All 11 responded positively to lactate but not to placebo, and they each experienced an at least 75% reduction in symptoms during the 6-month follow-up period. Detailed case reports of three of these patients are presented. CONCLUSIONS: These findings support the construct and predictive diagnostic validity of nonfearful panic disorder as a subtype of panic disorder and suggest that a lack of attention to this group leads to both the underestimation of the prevalence of panic disorder and to the withholding of potentially successful treatments for this group.     

Surreptitious drug use by patients in a panic disorder study

In a double-blind, placebo-controlled trial comparing alprazolam and imipramine for panic disorder, serum analysis revealed that a substantial proportion of the patients took explicitly prohibited anxiolytic medication. Excluding these patients changed the results.     

Coping behavior in patients with panic disorder

The purpose of the present paper was to investigate the role of coping behavior in patients with panic disorder (PD). This was done by evaluating three items of coping behavior (seeking of social support, wishful thinking and avoidance) in the Ways of Coping Checklist. The subjects consisted of 30 patients with PD (26 with agoraphobia). Coping behavior and the severity of PD was investigated at baseline and at 24 months (the final outcome). At baseline there were no gender differences in coping behavior. The severity of panic attacks significantly correlated with that of agoraphobia. The baseline severity of PD (panic attacks and agoraphobia) did not correlate with coping behavior. At the outcome assessment there was no significant correlation between the severity of panic attack and coping behavior. The severity of agoraphobia at final outcome and the coping behavior (seeking of social support) at baseline were significantly correlated. In the group that had remission in agoraphobia (the good outcome group), the severity of agoraphobia at baseline was significantly lower and the seeking of social support coping behavior was significantly higher than that of the poor outcome group. No significant difference in panic attack severity was noted between the good and poor outcome groups. Discriminant analysis revealed that seeking of social support coping behavior was a significant discriminant factor of agoraphobia. Although these are preliminary data, special coping behavior might be related to improvement of agoraphobia in patients with PD.     

Smoking in patients with panic disorder.

We compared smoking prevalence in 217 patients with panic disorder with that in 217 age- and sex-matched control subjects who were obtained by telephone survey from the same neighborhoods. Data were obtained for current smoking habits and smoking status at either the onset of illness (patients) or 10 years previously (control subjects). Patients had been ill for 10.6 (SD = 10.0) years. Female patients with panic disorder had a significantly higher smoking prevalence at the onset of their illness than did control subjects 10 years previously (54% vs. 35%). The current smoking prevalence for female patients was also significantly higher than that of control subjects (40% vs. 25%). Male smoking rates did not differ between patients and control subjects. Caffeine use did not appear to explain these findings. These data suggest a link between smoking behavior and panic disorder in women.     

Decreased R-R variance in panic disorder patients

To investigate autonomic function in panic disorder patients (n = 30), we compared postural changes in heart rate and the R-R interval variance in patients and normal controls (n = 20). There was no significant difference in the immediate changes in heart rate upon standing between the groups. R-R variance was significantly decreased during resting supine condition in patients as indicated by the corrected standard deviation of the R-R intervals. The standing R-R variance was significantly lower than that of normal controls as indicated by the corrected standard deviations, the corrected mean consecutive difference and the corrected standard deviation of the mean consecutive difference of the R-R intervals, suggesting an increase in vagal withdrawal in patients, especially upon standing. If this finding is specific to panic disorder patients, it may be a useful peripheral marker for this condition.