Effects of tryptophan depletion and tryptophan loading on the affective response to high-dose CO2 challenge in healthy volunteers

It has been reported that in panic disorder (PD), tryptophan depletion enhances the vulnerability to experimentally induced panic, while the administration of serotonin precursors blunts the response to challenges. Using a high-dose carbon dioxide (CO2) challenge, we aimed to investigate the effects of acute tryptophan depletion (ATD) and acute tryptophan loading (ATL) on CO2-induced panic response in healthy volunteers. Eighteen healthy volunteers participated in a randomized, double-blind placebo-controlled study. Each subject received ATD, ATL, and a balanced condition (BAL) in separate days, and a double-breath 35% CO2 inhalation 4.5 h after treatment. Tryptophan (Trp) manipulations were obtained adding 0 g (ATD), 1.21 g (BAL), and 5.15 g (ATL) of l-tryptophan to a protein mixture lacking Trp. Assessments consisted of a visual analogue scale for affect (VAAS) and panic symptom list. A separate analysis on a sample of 55 subjects with a separate-group design has also been performed to study the relationship between plasma amino acid levels and subjective response to CO2. CO2-induced subjective distress and breathlessness were significantly lower after ATD compared to BAL and ATL (p <0.05). In the separate-group analysis, Delta VAAS scores were positively correlated to the ratio Trp:I LNAA pound after treatment (r = 0.39; p <0.05). The present results are in line with preclinical data indicating a role for the serotonergic system in promoting the aversive respiratory sensations to hypercapnic stimuli (Richerson, Nat Rev Neurosci 5(6):449-461, 2004). The differences observed in our study, compared to previous findings in PD patients, might depend on an altered serotonergic modulatory function in patients compared to healthy subjects

Psychiatric screening and interventions for minor refugees in Europe: an overview of approaches and tools

Currently hundreds of thousands of minor refugees entered Europe. This group has been exposed to traumatic events pre-, during, and post-migration and is at increased risk of developing psychiatric disorders. In this article, we describe the results of our literature search on screening and interventions for post-traumatic stress disorder (PTSD) in minor refugees, in order to make recommendations for clinical practice. Results show that studies on diagnostic accuracy of assessment instruments and efficacy of mental healthcare interventions in this population are lacking. Traumatic experiences pre-flight, during the flight and at resettlement, superimposed by parental PTSD, and other contextual factors, might lead to more than 25% of minor refugees developing PTSD. Conclusion: To enhance the number of minor refugees recognized with PTSD, we recommend the use of a brief screening instrument. A public health approach, focusing on environmental supportive factors is the first step in treatment for this group, followed by short-term psychological group interventions focusing on psycho-education and stress reduction. Minor refugees with no improvement in PTSD symptoms by these interventions need referral to specialized mental health care services. Mental health providers should be culturally competent.What is Known: Post-traumatic stress disorder, anxiety, sleeping problems, and depression are the most common psychiatric disorders in minor refugees. Evidence based methods on screening and interventions in minor refugees with psychiatric disorders are lacking. What is New: In the absence of validated screening tools a best practice reliable, quick and child-friendly tool is presented. <A layered system for mental health care and psychosocial support in minor refugees is explaine