Nitrous oxide (NO), also known as “laughing gas” is a colorless gas used as an anesthetic, a propellant in some foods, an engine performance enhancer and a recreational drug. When inhaled, it is known to provoke a rapid feeling of euphoria or excitement for a short period of time, dissociative phenomena and sometimes laughter. As its fellow anesthetic agent and NMDA-receptor antagonist, ketamine, NO is being studied for its possible therapeutic profile in treatment resistant major depression (TRMD).

TRMD is a serious illness, that urges for effective alternative treatments. In that regard, we explored the recent studies conducted in these patients, using NO in different dosages when compared to placebo.

The authors revised the published literature about this topic, selecting relevant articles with the topic words: “Depression”, “Treatment Resistant Major Depression” and “Nitrous Oxide” in scientific data base.

Since 2018, at least two randomized clinical trials have demonstrated that NO has considerable antidepressant effects in TRMD, when compared to placebo. Investigators noted that these positive effects where maintained at least for two weeks after a single 1-hour inhalation. In a more recent study, scientists compared different NO concentrations (25% vs. 50%) concluding that the 25% concentration had similar efficacy with a lower risk of adverse effects.

There appears to be encouraging results when treating patients with TRMD with NO in a 25% concentration. Nonetheless, there is need for further investigation, namely through studies that compare NO with other valid TRMD treatments and not only versus placebo.

No significant relationships.

Aripiprazole (ARI) is an atypical antipsychotic drug with D2 partial agonist properties, usually prescribed to treat mood disorders (major depression or bipolar disorder) and schizophrenic disorder (schizophrenia or schizoaffective disorder). Dopamine receptor agonists, as is ARI, have been implicated in some cases of impulse-control problems, such as gambling disorder (GD), increased spending, hypersexuality and compulsive eating.

Currently, it is hypothesized that aripiprazole may cause impulse-control problems because it can produce a hyperdopaminergic state in the mesolimbic pathway (reward system) through its predominant action on dopamine D3 receptors. We intend to do a non-systematic review of the scientific information regarding this subject.

The authors revised the published literature about this topic, selecting relevant articles, systematic reviews and case reports, with the topic words: “aripiprazol”, “gambling disorder” and “dopamine receptor” in scientific data base.

Overall, a few cases of ARI-induced pathological gambling as well as ARI-induced hypersexuality have been reported. In one study it was verified that comorbid psychiatric and substance use disorders were common among those who have experienced GD or worsened GD after beginning ARI treatment. In another study, it was verified that the group of patients who reported this alleged side-effect were mostly young (mean age, 33.6 years), mostly men (88.2%) and most lived alone.

Attributing to dopamine agonists the only factor that can explain the onset of GD is simplistic and dangerous. Many other potential risk factors, including individual vulnerability factors (temperament, genetics) as well as environmental factors, must be considered.

No significant relationships.

Patients unsuccessfully treated by neurostimulation may represent a highly intractable subgroup of depression. While the efficacy of intravenous (IV) ketamine has been established in patients with treatment-resistant depression (TRD), there is an interest to evaluate its effectiveness in a subpopulation with a history of neurostimulation.

This retrospective, posthoc analysis compared the effects of four infusions of IV ketamine in 135 (x̄ = 44 ± 15.4 years of age) neurostimulation-naïve patients to 103 (x̄ = 47 ± 13.9 years of age) patients with a history of neurostimulation. The primary outcome evaluated changes in depression severity, measured by the Quick Inventory for Depression Symptomatology-Self Report 16-Item (QIDS-SR16). Secondary outcomes evaluated suicidal ideation (SI), anxiety severity, measured by the Generalized Anxiety Disorder 7-Item (GAD-7), and consummatory anhedonia, measured by the Snaith–Hamilton Pleasure Scale (SHAPS).

Following four infusions, both cohorts reported a significant reduction in QIDS-SR16 Total Score (F (4, 648) = 73.4, P < .001), SI (F (4, 642) = 28.6, P < .001), GAD-7 (F (2, 265) = 53.8, P < .001), and SHAPS (F (2, 302) = 45.9, P < .001). No between-group differences emerged. Overall, the neurostimulation-naïve group had a mean reduction in QIDS-SR16 Total Score of 6.4 (standard deviation [SD] = 5.3), whereas the history of neurostimulation patients reported a 4.3 (SD = 5.3) point reduction.

IV ketamine was effective in reducing symptoms of depression, SI, anxiety, and anhedonia in both cohorts in this large, well-characterized community-based sample of adults with TRD.

5-HTTLPR (serotonin transporter linked polymorphic region) has long (l) and short (s) allelic variations. The s allele is linked to depression, anxiety, and slower response to selective serotonin reuptake inhibitors (SSRI). Both depression and SSRI's are associated with bone loss and fractures. We explored the relationship between the 5-HTTLPR and bone loss.

IRB-approved retrospective chart review of adult psychiatric patients during a 10-year period with both 5-HTTLPR genotype and bone mineral density (BMD) assessment (hip and spine BMD stratified by age, Z-scores < 50, T-scores ≥50 years). Age, gender, and BMD scores were compared between the 5-HTTLPR categories of s allele (l/s and s/s genotypes) versus l/l genotype using one-way ANOVA.

Of 3016 with 5-HTTLPR genotyping, 239 had BMD, with 157 (66%) s allele and 82 (34%) l/l genotypes. Among men and women < 50 years, s allele had lower Z-scores in the hip (−0.6628/n=43 vs −0.1306/n=36, p=0.012) and spine (−0.9762/n=42 vs -0.1000/n=41, p=0.0019) than l/l. There were no differences in T-scores between the s allele and l/l genotypes for men and women ≥50 years. Gender analysis (n=198 women, n=41 men) showed women with s allele had lower Z-scores in the hip (−0.68182/n=33 vs −0.08788/n=33, p=0.0146) and spine (−1.0250/n=32 vs − 0.0586/n=29, p=0.0020) than the l/l genotype.

The s allele is associated with lower bone density at the hip and spine in younger adults, particularly in younger women. Our results suggest 5-HTTLPR variants may mediate serotonin effects on bone in a gender-specific or hormonal/ menopausal-dependent interaction.

Local health departments (LHDs) have little guidance for operationalizing community resilience (CR). We explored how community coalitions responded to 4 CR levers (education, engagement, partnerships, and community self-sufficiency) during the first planning year of the Los Angeles County Community Disaster Resilience (LACCDR) Project.

Sixteen communities were selected and randomly assigned to the experimental CR group or the control preparedness group. Eight CR coalitions met monthly to plan CR-building activities or to receive CR training from a public health nurse. Trained observers documented the coalitions’ understanding and application of CR at each meeting. Qualitative content analysis was used to analyze structured observation reports around the 4 levers.

Analysis of 41 reports suggested that coalitions underwent a process of learning about and applying CR concepts in the planning year. Groups resonated with ideas of education, community self-sufficiency, and engagement, but increasing partnerships was challenging.

LHDs can support coalitions by anticipating the time necessary to understand CR and by facilitating engagement. Understanding the issues that emerge in the early phases of planning and implementing CR-building activities is critical. LHDs can use the experience of the LACCDR Project’s planning year as a guide to navigate challenges and issues that emerge as they operationalize the CR model. (Disaster Med Public Health Preparedness. 2016;10:812–821)