Infrequency of "pure" GAD: impact of psychiatric comorbidity on clinical course

Chronicity, relapse, and illness--course of panic disorder, social phobia, and generalized anxiety disorder: findings in men and women from 8 years of follow-up

Anxiety disorders are chronic illnesses that occur more often in women than men. Previously, we found a significant sex difference in the 5-year clinical course of uncomplicated panic disorder that was attributable to a doubling of the illness relapse rate in women compared to men. However, we have not detected a sex difference in the clinical course of panic with agoraphobia, generalized anxiety disorder (GAD), or social phobia (SP), which are conditions generally thought to be more chronic than uncomplicated panic disorder. Given that a longer follow-up period may be required to detect differences in clinical course for more enduring illnesses, we conducted further analyses on this same cohort after a more protracted interval of observation to determine whether sex differences would emerge or be sustained. Data were analyzed from the Harvard/Brown Anxiety Research Program (HARP), a naturalistic, longitudinal study that repeatedly assessed patients at 6 to 12 month intervals over the course of 8 years. Data regarding remission and relapse status were collected from 558 patients and treatment was observed but not prescribed. Cumulative remission rates were equivalent among men and women with all diagnoses. Patients who experienced remission were more likely to improve during the first 2 years of study. Women with GAD continued remitting late into the observation period and experienced fewer overall remission events by 8 years. However, the difference in course failed to reach statistical significance. Relapse rates for women were comparable to those for men who suffered from panic disorder with agoraphobia, GAD, and SP. Again, initial relapse events were more likely to occur within the first 2 years of observation. However, relapse events for uncomplicated panic in women were less restricted to the first 2 years of observation and by 8 years, the relapse rates for uncomplicated panic was 3-fold higher in women compared with men. Anxiety disorders are chronic in the majority of men and women, although uncomplicated panic is characterized by frequent remission and relapse events. Short interval follow-up shows sex differences in the remission and relapse rates for some but not all anxiety disorders. These findings suggest important differences in the clinical course among the various anxiety disorders and support nosological distinctions among the various types of anxiety. It may be that sex differences in the clinical course of anxiety disorders hold prognostic implications for patients with these illnesses.

Exposure of mice to a predator odor increases acoustic startle but does not disrupt the rewarding properties of VTA intracranial self-stimulation

The present investigation assessed the propensity of an acute psychogenic stressor exposure to induce behavioral change in paradigms assessing fear/anxiety (acoustic startle) and motivation/anhedonia (intracranial self-stimulation) in CD-1 mice. In the acoustic startle paradigm, a 10-min exposure of 2-4 month old mice (young adult mice) to fox odor (2,5-dihydro-2,4,5-trimethylthiazoline; TMT) was associated with decreased acoustic startle relative to mice exposed to the control odor, butyric acid (BA), immediately and relative to both saline and BA exposure 24 h following odor exposure in the home cage. In contrast, a 2-min exposure of young adult mice to TMT was associated with an increase in startle relative to saline and BA during the immediate post-odor test session only. In young adult mice a 2-min and a 10-min exposure to BA resulted in a startle profile of mice reminiscent of saline-treated mice. In comparison to young adult mice, a 2-min exposure of mature adult mice (5-7 months old) to TMT enhanced startle for up to 48 h relative to both saline and BA, while a 10-min exposure of mature adult mice to TMT enhanced startle for 168 h post-odor exposure relative to saline-exposed mice only. However, the greatest increase in startle amplitude (i.e. 48 h) was acquired following the 2-min exposure of mature mice to TMT. Among mature adult mice, a 10-min exposure to BA in the home cage eventuated in enhanced startle relative to saline-exposed animals 168 h following odor exposure. In comparison, exposure of mice to 10 min of TMT depressed responding for VTA brain stimulation at the initial 80 Hz frequency, but was ineffective in elevating reward thresholds relative to mice merely exposed to saline. Mice assessed in the ICSS paradigm were approximately 2-4 months old at the time of surgery and 5-7 months old at the completion of testing. These data suggest that acute odor exposure may induce a fear gradient dependent upon the perceived stressor severity and that the resultant anxiety-like effects are dependent on the duration of odor exposure, age of the animals and the temporal interval between odor presentation and behavioral testing. Moreover, the anxiogenic properties of psychogenic stressors can be separated from their anhedonic effects. The implications of these data for clinical psychopathology are discussed.

Treating depression comorbid with anxiety--results of an open, practice-oriented study with St John's wort WS 5572 and valerian extract in high doses

Depressive disorders in comorbidity with anxiety disorders represent an frequently diagnostic and therapeutic problem. The studies quoted here prove that the symptoms associated with anxiety that severely afflict patients can be clearly improved more quickly with a combination therapy of St John's wort extract and valerian extract than with St John's wort monotherapy. The combination therapy was well tolerated, no significant side-effects occurred. Further studies are necessary to compare the combination treatment with other forms of therapy (serotonin- and noradrenalin re-uptake inhibitors).