The relationship between early administration of morphine or nitrous oxide gas and PTSD symptom development

Posttraumatic stress disorder prevalence and childbirth: update meta-analysis after the introduction of the DSM-5 and COVID-19 pandemic

PURPOSE

Meta-analyses were previously performed to estimate PTSD prevalence in the postpartum period. Significant events that could impact this outcome occurred in the last decade, such as the publication of the DSM-5 in 2013 and the COVID-19 pandemic in 2020. This systematic literature review with a meta-analysis addressed studies published after 2014 to estimate PTSD prevalence after childbirth.

METHOD

The methodological guidelines recommended by PRISMA were followed. The meta-analysis estimate was the proportion of PTSD cases. The restricted maximum likelihood (REML) was the method adopted for estimation in addition to multilevel random effect models. Subgroup analyses were performed to assess the impact of interest variables.

RESULTS

The estimated prevalence was 0.10 (95%CI: 0.8-0.13; I2 = 98.5%). No significant differences were found regarding the introduction of the DSM-5 (p = 0.73) or COVID-19 (p = 0.97), but instead, between low- and middle-income countries, e.g., the Middle East presents a higher prevalence (p < 0.01) than European countries.

CONCLUSIONS

There is a potential increase in PTSD prevalence rates after childbirth in the last decade not associated with the pandemic or the current diagnostic classification. Most studies showed a methodological fragility that must be overcome to understand this phenomenon better and support preventive actions and treatment for puerperal women.

The Differential Influence of PZM21, A Nonrewarding μ-opioid Receptor Agonist With G Protein Bias, on Behavioural Despair and Fear Response in Mice

A growing body of evidence points out the involvement of the µ-opioid receptors in the modulation of stress-related behaviour. It has been suggested that µ-opioid receptor agonists may attenuate behavioural despair following animals' exposure to an acute, inescapable stressor. Moreover, morphine was shown to ameliorate fear memories caused by a traumatic experience. As typical µ-opioid receptor agonists entail a risk of serious side effects and addiction, novel, possibly safer and less addictive agonists of this receptor are currently under investigation. One of them, PZM21, preferentially acting via the G protein signalling pathway, was previously shown to be analgesic, but less addictive than morphine. Here, we aimed to further test this ligand in stress-related behavioural paradigms in mice. The study has shown that, unlike morphine, PZM21 does not decrease immobility in the forced swimming and tail suspension tests. On the other hand, we observed that both mice treated with PZM21 and those receiving morphine presented a slight attenuation of freezing across the consecutive fear memory retrievals in the fear conditioning test. Therefore, our study implies that at the range of tested doses, PZM21, a nonrewarding representative of G protein-biased µ-opioid receptor agonists, may interfere with fear memory consolidation while having no beneficial effects on behavioural despair in mice.

Accelerated forgetting of a trauma-like event in healthy men and women after a single dose of hydrocortisone

Posttraumatic stress disorder (PTSD) is characterised by dysregulated hypothalamic-pituitary-adrenal axis activity and altered glucocorticoid receptor sensitivity. Early treatment with glucocorticoids may reduce PTSD risk, although the effect of such treatment on the aetiologically critical step of traumatic-memory-formation remains unclear. Here we examine the effects of exogenous cortisol (hydrocortisone) in a preclinical model of PTSD, using a factorial (Drug × Sex), randomised-controlled, double-blind design. Healthy men and women (n = 120) were randomised to receive 30 mg oral hydrocortisone or matched placebo immediately after watching a stressful film. Effects on film-related intrusions were assessed acutely in the lab, and ecologically using daily memory diaries for one week. We found that participants receiving hydrocortisone showed a faster reduction in daily intrusion frequency. Voluntary memory was assessed once, at the end of the week, but was unaffected by hydrocortisone. Exploratory analyses indicated sex-dependent associations between intrusions and baseline estradiol and progesterone levels. In men receiving hydrocortisone, higher baseline estradiol levels were associated with fewer intrusions, whereas women exhibited the opposite pattern. By contrast, progesterone levels were positively associated with intrusions only in men treated with hydrocortisone. The findings suggest that hydrocortisone promotes an accelerated degradation of sensory-perceptual representations underlying traumatic intrusive memories. In addition, while sex alone was not an important moderator, the combination of sex and sex-hormone levels (especially estradiol) influenced hydrocortisone's effects on involuntary aversive memories. Future well-powered experimental studies may provide a basis for a precision-psychiatry approach to optimising early post-traumatic glucocorticoid treatments that target intrusive memories, based on individual endocrinological profiles.

The safety and efficacy of Ketamine NMDA receptor blocker as a therapeutic intervention for PTSD review of a randomized clinical trial

OBJECTIVE

Posttraumatic stress disorder (PTSD) has long-lasting debilitating symptoms. PTSD causes a significant burden on healthcare workers and victims' families. The US Food Drug Administration (FDA) has approved only two Serotonin Selective Reuptake Inhibitors (SSRI), sertraline, and paroxetine as pharmacological interventions for PTSD. SSRI has a 50-60% response rate and up to 30% remission rate with a high relapse rate. Ketamine is an NMDA receptor blocker, has a rapid effective onset, a potent antidepressant with anti-suicidal, neuroprotective, and cognitive-enhancement properties.

METHOD

We retrieved randomized clinical trials (RCT) on PubMed, PubMed Central, and Medline Database of clinical trial studies until Jan/2022. We used the following keywords: "posttraumatic stress disorder. "AND "Ketamine." AND "Esketamine" AND "NMDA receptor antagonist" AND "treatment, pharmacological intervention, management. ". We used Medical Subject Heading [Mesh] Term for "ketamine" and "Esketamine" And "Receptors, N-Methyl-D-Aspartate" and "Stress Disorders, Post-Traumatic" and "Disease management.".

RESULT

All qualified five randomized clinical studies showed rapid and clear benefits of Ketamine infusion for PTSD symptoms resistant to conventional medications. The clinical improvements were evident in three of the four PTSD symptom categories, intrusions, avoidance, and negative alterations in cognitions and mood. In addition, Ketamine administration was safe well-tolerated, with transient dissociation as the main side effect reported. Ketamine infusion also positively affects comorbidities like chronic pain, alcohol use disorder, and major depression.

CONCLUSION

Ketamine showed fast, safe, highly effective pharmaceutical intervention for chronic PTSD symptoms. No correlation between ketamine potency and patient age, sex and/or body mass index. Further studies are needed to understand the appropriate therapeutic dose, onset, route of administration, duration of the treatment and comorbidity benefit.