Executive Functions in panic disorder: A mini-review

Altered Low Frequency Heart Rate Variability Associated with Agoraphobia in Panic Disorder: A Retrospective Study

PURPOSE

This study aimed to compare the clinical features of panic disorder (PD) with comorbid agoraphobia to those of PD alone. We focused on autonomic nervous system (ANS) alterations reflected in heart rate variability (HRV) and executive function deficits reflected in the Stroop test.

MATERIALS AND METHODS

We retrospectively compared psychometric features, Stroop test results, and resting-state HRV across three groups: a subclinical group with anxiety attack history, a PD group without agoraphobia, and a PD group with agoraphobia. The subclinical group included 10 male and 34 female, the PD without agoraphobia group included 17 male and 19 female, and the PD with agoraphobia group included 11 male and 18 female.

RESULTS

The PD with agoraphobia group had higher Symptom Checklist-95 scores than the other groups. Both PD groups had longer reaction times in the Stroop test than the subclinical group. There were no significant differences in HRV parameters between the PD groups with and without agoraphobia. Compared with the subclinical group, the PD with agoraphobia group showed significantly lower values of the natural logarithm of low-frequency HRV.

CONCLUSION

Our results do not support that executive function deficits and ANS alterations are more pronounced with comorbid agoraphobia among PD groups. However, PD with agoraphobia patients showed more complex and severe clinical symptoms in their self-reports. Compared with the subclinical group, PD patients with agoraphobia showed specific features in the natural logarithm of low-frequency HRV. Our findings suggest that agoraphobia comorbidity should be considered when evaluating or treating patients with PD.

Data-Driven Pupil Response Profiles as Transdiagnostic Readouts for the Detection of Neurocognitive Functioning in Affective and Anxiety Disorders

BACKGROUND

Neurocognitive functioning is a relevant transdiagnostic dimension in psychiatry. As pupil size dynamics track cognitive load during a working memory task, we aimed to explore if this parameter allows identification of psychophysiological subtypes in healthy participants and patients with affective and anxiety disorders.

METHODS

Our sample consisted of 226 participants who completed the n-back task during simultaneous functional magnetic resonance imaging and pupillometry measurements. We used latent class growth modeling to identify clusters based on pupil size in response to cognitive load. In a second step, these clusters were compared on affective and anxiety symptom levels, performance in neurocognitive tests, and functional magnetic resonance imaging activity.

RESULTS

The clustering analysis resulted in two distinct pupil response profiles: one with a stepwise increasing pupil size with increasing cognitive load (reactive group) and one with a constant pupil size across conditions (nonreactive group). A larger increase in pupil size was significantly associated with better performance in neurocognitive tests in executive functioning and sustained attention. Statistical maps of parametric modulation of pupil size during the n-back task showed the frontoparietal network in the positive contrast and the default mode network in the negative contrast. The pupil response profile of the reactive group was associated with more thalamic activity, likely reflecting better arousal upregulation and less deactivation of the limbic system.

CONCLUSIONS

Pupil measurements have the potential to serve as a highly sensitive psychophysiological readout for detection of neurocognitive deficits in the core domain of executive functioning, adding to the development of valid transdiagnostic constructs in psychiatry.

Thiol disulfide homeostasis in psychiatric disorders: A comprehensive review

Thiol-disulfide couple maintains an intracellular redox status. Dynamic thiol-disulfide homeostasis acts crucial parts in metabolic processes involving signal mechanisms, inflammation, antioxidant defense. Thiol-disulfide homeostasis have been implicated in numerous diseases. In this comprehensive review we identified the studies that examined the thiol-disulfide homeostasis in psychiatric disorders. Most cases demonstrated alterations in thiol-disulfide homeostasis and in most of them the thiol-disulfide balance tended to change direction to the disulfide side, that is, to the oxidative side. Currently, the fact that N-acetylcysteine, a thiol-containing compound, is of great interest as a new treatment approach in psychiatric disorders and the role of glutathione, the most abundant thiol, in the brain highlights the importance of evaluating the thiol-disulfide balance in psychiatric disorders.

Serum BDNF levels are involved in the diagnosis and treatment response in patients with PD

BACKGROUND

The study aimed to explore whether brain-derived neurotrophic factor (BDNF) could be predictive for the diagnosis of panic disorder (PD) and to explore the association between serum BDNF levels and the treatment response to escitalopram in PD patients.

METHODS

Ninety PD patients and 99 healthy controls (HCs) were finally recruited. PD patients were treated only by escitalopram for 8 weeks. All patients were administered the Short-Form Health Survey-36 (SF-36), Hamilton Anxiety Rating Scale (HAMA-14), and State-Trait Anxiety Inventory (STAI) to assess life quality, anxiety symptoms and trait, respectively. Neuropsychological tests were assessed at baseline in all participants. Besides, peripheral venous blood was drawn from all participants for BDNF serum levels detection both at baseline and after 8 weeks of treatment.

RESULTS

In PD patients, the baseline serum BDNF levels were lower than HCs. The area under the ROC curve (AUC) of baseline serum BDNF levels predicting PD from HCs was 0.947 (94.9 % for sensitivity, 77.8 % for specificity). The baseline serum BDNF levels (beta = 0.276, p = 0.007), the current duration (beta = -0.301, p = 0.004), and trait anxiety (TAI) (beta = 0.201, p = 0.045) were predictors for reduction rates of HAMA-14 after 8 weeks' escitalopram treatment.

LIMITATIONS

A long-term observation and high homogeneity of sample may make the results more convincing.

CONCLUSION

This preliminary finding highlighted the value of serum BDNF levels for the diagnosis of PD. In addition, the higher baseline serum BDNF levels may predict the better escitalopram treatment response in PD patients.