Assessing the effect of selective serotonin reuptake inhibitors in the prevention of post-acute sequelae of COVID-19

Background

Post-acute sequelae of COVID-19 (PASC) produce significant morbidity, prompting evaluation of interventions that might lower risk. Selective serotonin reuptake inhibitors (SSRIs) potentially could modulate risk of PASC via their central, hypothesized immunomodulatory, and/or antiplatelet properties although clinical trial data are lacking.

Materials and Methods

This retrospective study was conducted leveraging real-world clinical data within the National COVID Cohort Collaborative (N3C) to evaluate whether SSRIs with agonist activity at the sigma-1 receptor (S1R) lower the risk of PASC, since agonism at this receptor may serve as a mechanism by which SSRIs attenuate an inflammatory response. Additionally, determine whether the potential benefit could be traced to S1R agonism. Presumed PASC was defined based on a computable PASC phenotype trained on the U09.9 ICD-10 diagnosis code.

Results

Of the 17,908 patients identified, 1521 were exposed at baseline to a S1R agonist SSRI, 1803 to a non-S1R agonist SSRI, and 14,584 to neither. Using inverse probability weighting and Poisson regression, relative risk (RR) of PASC was assessed.A 29% reduction in the RR of PASC (0.704 [95% CI, 0.58-0.85]; P = 4 ×10-4) was seen among patients who received an S1R agonist SSRI compared to SSRI unexposed patients and a 21% reduction in the RR of PASC was seen among those receiving an SSRI without S1R agonist activity (0.79 [95% CI, 0.67 - 0.93]; P = 0.005).Thus, SSRIs with and without reported agonist activity at the S1R were associated with a significant decrease in the risk of PASC.

Selective Serotonin Reuptake Inhibitor Prescribing Within An Integrated Pediatric Primary Care Behavioral Health Program

OBJECTIVE

Selective serotonin reuptake inhibitor (SSRI) prescribing is increasingly being integrated into primary care but few data are available about prescribing patterns by pediatric primary care clinicians (PCCs) following implementation of integrated behavioral health (BH) care.

METHODS

Using administrative claims data, we performed a cross-sectional analysis of SSRI prescribing within a statewide pediatric primary care network over 10 years after initiation of an integrated BH program, calculating the rate of PCC and specialist SSRI prescribing. Using electronic health record data, we analyzed a proposed set of quality metrics for SSRI initiation.

RESULTS

Over 10 years, SSRI prescribing by PCCs increased from 56 fills/1000 patient-years to 446; over the same time period, prescribing by specialists for the network's patients rose from 233 fills/1000 patient-years to 380. In 2013, PCCs prescribed 19% of all SSRIs while by 2022 they prescribed 54% of the total (P<0.001 for change for PCCs compared to specialists). Among 16272 initial SSRI prescribing events by PCCs, 99.6% prescribed a recommended SSRI; 97.5% used an appropriate starting dose; 55.2% documented a validated symptom rating scale at initiation; 53.4% had a contact within 14 days; 67.8% had a follow-up visit within 60 days; and 37.4% documented a symptom rating scale within 60 days.

CONCLUSIONS

In the first 10 years of a pediatric integrated BH program, SSRI prescribing by PCCs increased over seven-fold and surpassed specialist prescribing for the patient population. PCCs chose medications and starting doses appropriately but could improve their use of validated symptom rating scales and consistent follow-up.

DNA methylation of serotonin genes as predictive biomarkers of antidepressant treatment response

Selective serotonin reuptake inhibitors (SSRI) are frequently ineffective in treating depressive episodes and biomarkers are needed to optimize antidepressant treatment outcomes. DNA methylation levels of serotonin transporter (SLC6A4) and tryptophan hydroxylase 2 genes (TPH2) have been suggested to predict antidepressant clinical outcomes but their applicability remains uncertain. In this study, we: 1) evaluated SLC6A4/TPH2 methylation biomarker potential for predicting clinical outcomes after escitalopram treatment; 2) evaluated whether changes in SLC6A4/TPH2 methylation are informative of treatment mechanisms. We used a cohort of 90 unmedicated patients with major depressive disorder that were part of a 12-week open-label longitudinal trial and compared our observations with previous findings. Depressive symptoms were measured at baseline and after 8 and 12 weeks of treatment using the Hamilton Depression Rating Scale (HAMD6/17). We found an association between baseline TPH2 methylation and both clinical response (β:3.43; p = 0.01; 95 % CI:[0.80; 6.06]) and change in depressive symptoms after 8 weeks (β:-45.44; p = 0.01; 95 %CI:[- -78.58; -12.30]). However, we found no evidence for predictive value of any gene (TPH2 AUC: 0.74 95 % CI:[0.42;0.79]; SLC6A4: AUC: 0.61; 95 % CI: [0.48-0.78]). Methylation levels changed at the trend level for CpG sites of SLC6A4 and TPH2 over the course of 12 weeks of treatment. In addition, similar to previous observations, we found a trend for an association between methylation of SLC6A4 CpG2 (chr17:30,236,083) and HAMD17 change after 12 weeks. Our findings suggest that although TPH2 and SLC6A4 methylation may be informative of antidepressant treatment outcome, they are unlikely to prove useful as clinical predictor tools.

Efficacy and safety of add-on sarcosine in patients with major depressive disorder: A randomized controlled trial

The main hurdles with current therapies for major depressive disorder (MDD) include lack of efficacy, therapeutic latency, and adverse drug reactions. Add-on therapy to conventional antidepressants may result in better therapeutic outcomes to overcome these obstacles. Sarcosine (N-methyl glycine), an endogenous amino acid that acts by modulating the NMDA receptor, is available as a dietary supplement. So, the present study was planned to evaluate the efficacy and safety of add-on sarcosine to SSRIs in MDD. In the present randomized, double-blind clinical trial (NCT04975100), 60 eligible participants with MDD were randomly assigned to either the test group (SSRI + sarcosine) or the control group (SSRI + placebo). Clinical and biochemical parameters like MADRS, CGI, serum BDNF, and serum glycine were assessed at baseline and eight weeks. The mean reduction in MADRS score was significant in both the control (-8.7, 95% CI: -11.0 to -6.4, p < 0.001) and the test group (-13.3, 95% CI: -14.9 to -11.7, p < 0.001), but the change in the test group was significantly greater (-4.6, 95% CI: -7.5 to -1.7, p = 0.003). The test group had a significantly higher response rate (p = 0.007) and remission rate (p = 0.038) compared to the control group. There was a significant increase in serum BDNF in both groups; however, the change in the test group was significantly higher than in the control group (p = 0.041). Similarly, the test group had a significantly higher increase in serum glycine than the control group (p < 0.001). Sarcosine may be considered an efficacious and safe add-on therapy to standard SSRIs in the management of MDD. ClinicalTrial.gov IdentifierNCT04975100.

Frequency of self-reported persistent post-treatment genital hypoesthesia among past antidepressant users: a cross-sectional survey of sexual and gender minority youth in Canada and the US

PURPOSE

Persistent post-treatment genital hypoesthesia (PPTGH) is a primary symptom of post-SSRI sexual dysfunction (PSSD), an iatrogenic syndrome characterized by enduring sexual dysfunction following the discontinuation of some antidepressants. We aimed to estimate the frequency of PPTGH among past users of psychiatric treatments, particularly antidepressants.

METHODS

We used a subsample of UnACoRN, a US/Canada survey of sexual and gender minority youth aged 15 to 29. We included participants with a history of psychiatric drug use. We excluded individuals with genital surgeries or without sexual experience. The analysis involved chi-square tests for initial group comparisons, post hoc tests for multiple comparisons, and logistic regression among those who had stopped taking medication. We exponentiated the regression to estimate the odds of PPTGH by drug type, adjusting for age, sex-assigned-at-birth, hormone treatment, and depression severity in three nested models.

RESULTS

574 of 2179 survey participants reported genital hypoesthesia. They were older and more likely to report male sex assignment at birth, hormonal therapy history, and psychiatric drug history. The frequency of PPTGH among antidepressant users was 13.2% (93/707) compared to 0.9% (1/102) among users of other medications; adjusted odds ratio: 14.2 (95% CI: 2.92 to 257).

CONCLUSION

Antidepressant discontinuation is strongly associated with PPTGH in the US and Canada where SSRI/SNRI medications account for 80% of antidepressant prescriptions. We call for standardized international warnings and transparent, informed consent. Future research should expand upon our efforts to estimate the risk of PSSD by including all the proposed diagnostic criteria, including documentation of temporal changes in PSSD-related symptoms before and after treatment (≥3 months).

Antidepressant class and concurrent rTMS outcomes in major depressive disorder: a systematic review and meta-analysis

Background

Repetitive transcranial magnetic stimulation (rTMS) is frequently used as an adjunctive treatment with antidepressants for depression. We aimed to evaluate the clinical efficacy and safety of antidepressant classes when administered concurrently with rTMS for the management of major depressive disorder (MDD).

Methods

In this systematic review and meta-analysis, MEDLINE, Embase, PsycINFO, and the Cochrane Library were searched from inception to April 12th 2024 for terms relating to medication, depression, and rTMS and appraised by 2 independent screeners. All randomized clinical trials that prospectively evaluated a specific antidepressant adjunctively with sham rTMS as a control in MDD were included. The study was registered with PROSPERO (CRD42023418435). The primary outcome measure assessed symptomatic improvement measured by formal depression scales. We used a random-effects model with pooled Standardized Mean Differences (SMDs) and log odds ratios (OR). All studies were assessed for their methodological quality and bias using the Cochrane Collaboration Risk of Bias tool version 2 (RoB2).

Findings

14 articles from 5376 identified studies were included in the systematic review and meta-analysis. There was only sufficient trial data to evaluate the effects of rTMS and combination therapy with selective serotonin reuptake inhibitors (SSRIs) and selective norepinephrine reuptake inhibitors (SNRIs). Across studies, 848 participants (mean [SD] age:41.1 [18.7] years for SSRIs, 51.8 [3.8] years for SNRIs) prospectively examined the efficacy of antidepressant medication with rTMS. Combining rTMS with SSRIs led to significantly lower depression scores, (SMD [CI] of -0.65 [-0.98, -0.31], p = 0.0002, I2 = 66.1%), higher response (OR = 0.97 [0.50, 1.44], p < 0.0001, I2 = 25.33%) and remission rates (OR = 1.04 [0.55, 1.52], p < 0.0001, I2 = 0.00%) than medication with sham rTMS. No additive benefit was found for SNRIs with rTMS (SMD of 0.10 [-0.14, 0.34], p = 0.42, I2 = 0.00%; OR = 0.12 [-0.39, 0.62], p = 0.64, I2 = 0.00%; OR = -0.31 [-0.90, 0.28], p = 0.86, I2 = 39.9%). The overall risk of bias for the included studies ranged from low to high, with 1 study having a high risk of bias.

Interpretation

The combination of rTMS with SSRIs, but not SNRIs, significantly reduced depression severity, increasing response and remission rates. Some analyses demonstrated high heterogeneity, which was influenced by an SSRI trial with a high effect size. Overall, these results suggest that not all antidepressant combination therapies are alike, and SSRIs should be considered when initiating rTMS.

Funding

Donald T. Stuss Young Investigator Research Innovation Award from the Sandra Black Centre for Brain Resilience & Recovery and the Harquail Centre for Neuromodulation through the Sunnybrook Foundation.

Neuropathological implication of high blood bilirubin in patients and model rats with depression

PURPOSE

Elevated bilirubin levels have been associated with major depressive disorder (MDD); however, the exact impact of bilirubin on MDD and the underlying molecular mechanisms remain unclear. Here, we explored the influence of bilirubin on MDD and sought to identify the mechanisms via which bilirubin induces depressive-like behavior.

PATIENTS AND METHODS

Forty patients who were diagnosed with MDD and received treatment with selective serotonin reuptake inhibitors (SSRIs) were included, with 43 healthy volunteers serving as controls. Clinical symptoms were evaluated using Hamilton depression rating scale-24 (HAMD-24) and the Hamilton anxiety rating scale. Serum concentrations of total bilirubin (TBIL) and indirect bilirubin (IBIL) were measured at baseline and after treatment using an automated biochemical analyzer. The connection between clinical symptoms and TBIL or IBIL was examined using Pearson correlation. Chronic restraint stress (CRS) was employed to generate a rat model of depression. TBIL, IBIL in rat serum were measured by ELISA. Reactive oxygen species (ROS) contents in rat hippocampal tissues were quantified by flow cytometry. The levels of microglial markers and the extent of neuronal damage in the rat hippocampus were assessed by immunofluorescence and transmission electron microscopy, respectively.

RESULTS

Serum TBIL and IBIL levels were higher in patients with MDD than in the healthy controls. After treatment with SSRIs, the serum levels of TBIL and IBIL in MDD patients were significantly reduced. The levels of TBIL and IBIL were associated with HAMD-24 in MDD patients. Compared with the controls, the serum levels of TBIL, IBIL and the hippocampal ROS contents were elevated in CRS-exposed rats. Fluoxetine lowered inflammatory factor levels, mitigated oxidative stress.

CONCLUSION

Our findings indicate a possible correlation between elevated serum bilirubin and depressive symptoms. Increases in ROS levels, along with neuronal damage, may represent pathological mechanisms underlying MDD.

Frontal Alpha Asymmetry and Its Modulation by Monoaminergic Neurotransmitters in Depression

Frontal alpha asymmetry (FAA) is an electroencephalography (EEG) measure that quantifies trait-like left versus right hemisphere lateralization in alpha power. Increased FAA indicates relatively greater left than right frontal cortex activation and is associated with enhanced reward-related approach behaviors rather than avoidance or withdrawal. Studies dating back several decades have often suggested that having greater FAA supports enhanced positive affect and protection against major depressive disorder (MDD), whereas having greater right frontal activation (i.e., reduced FAA) is associated with negative affect and risk for MDD. While this hypothesis is widely known, a number of other studies instead have found increased FAA in MDD, or evidence that either leftward or rightward bias in FAA is associated with depression. Here we briefly review the literature on leftward or rightward lateralization in FAA in MDD, and find much evidence that MDD is not always characterized by reduced FAA. We also review the limited literature on FAA and monoaminergic neurotransmitter systems, including pharmacologic agents that act on them. Studies of serotonin in particular provide genetic and pharmacologic evidence for modulation of FAA, where some of these data may suggest that serotonin reduces FAA. In a synthesis of the collective literature on FAA and the monoamines, we suggest that serotonin and norepinephrine may differentially affect FAA, with serotonin tending to promote right frontal activation and norepinephrine biased toward left frontal activation. These putative differences in frontal lateralization may influence MDD phenotypes or potential subtypes of the disorder, and suggest pharmacologic treatment strategies.

Effects of antidepressants on brain structure and function in patients with obsessive-compulsive disorder: A review of neuroimaging studies

Obsessive-compulsive disorder (OCD) affects 2-3% of people worldwide. Although antidepressants are the standard pharmachological treatment of OCD, their effect on the brain of individuals with OCD has not yet been fully clarified. We conducted a systematic search on PubMed, Scopus, Embase, and Web of Science to explore the effects of antidepressants on neuroimaging findings in OCD. Thirteen neuroimaging investigations were included. After antidepressant treatment, structural magnetic resonance imaging studies suggested thalamic, amygdala, and pituitary volume changes in patients. In addition, the use of antidepressants was associated with alterations in diffusion tensor imaging metrics in the left striatum, the right midbrain, and the posterior thalamic radiation in the right parietal lobe. Finally, functional magnetic resonance imaging highlighted possible changes in the ventral striatum, frontal, and prefrontal cortex. The small number of included studies and sample sizes, short durations of follow-up, different antidepressants, variable regions of interest, and heterogeneous samples limit the robustness of the findings of the present review. In conclusion, our review suggests that antidepressant treatment is associated with brain changes in individuals with OCD, and these results may help to deepen our knowledge of the pathophysiology of OCD and the brain mechanisms underlying the effects of antidepressants.

Dataset for clinical parameters and disease transcriptome networks associated with exposure to citalopram in zebrafish (Danio rerio) larvae

Citalopram, a selective serotonin reuptake inhibitor (SSRI), is often detected in aquatic ecosystems. In this investigation, developing zebrafish were continuously exposed to one nominal concentration of either 0, 10, or 1000 µg/L citalopram for 7 days. Ribonucleic acids were then extracted from zebrafish for RNA-sequencing using the NovoSeq 6000 (Illumina). Clean reads were obtained following the removal of both the adapter and poly-N sequences. Alignment and differential gene expression analysis was conducted using programs HISAT2 and StringTie assembler. Data were converted to FPKM to quantify differentially expressed transcripts. Significant clinical subnetworks enriched following citalopram exposure included sympathetic nerve activity, blood pressure, vascular tone, and arterial pressure. Regulated transcripts were related to diseases such as mechanical hyperalgesia, pain, inflammatory pain, obstructive hypertrophic cardiomyopathy, fatigue, Diamond-Blackfan anemia, and hypertrophic cardiomyopathy. Following exposure to 10 µg/L citalopram, several transcripts were linked to brain dysfunction like prostaglandin-endoperoxide synthase 2, microtubule associated protein tau, cathepsin B, and dystrophin. Genes related to cardiac dysfunction were altered in zebrafish following exposure to 1000 µg/L citalopram. Using literature and databases that describe gene interactions, molecular networks (clinical and disease networks) were constructed to understand effects of citalopram.

Eye disorders associated with selective serotonin reuptake inhibitors: a real-world disproportionality analysis of FDA adverse event reporting system

BACKGROUND

Selective serotonin reuptake inhibitors (SSRIs) are widely used in depression and other psychiatric disorders. Despite their efficacy, there is a growing concern about the risk of eye disorders. This study aims to explore the potential correlation between eye disorders and SSRIs utilizing real-world data.

RESEARCH DESIGN AND METHODS

The data were extracted from the US FDA Adverse Event Reporting System database from 2004Q1 to 2023Q3. The analysis focused on the clinical characteristics, the ranking of adverse reactions, the time-to-onset, and the severity proportion of SSRI-related eye disorders.

RESULTS

Our analysis revealed that SSRIs were significantly associated with eye disorders, with a higher risk of vision blurred with escitalopram, angle closure glaucoma with citalopram, and photopsia with paroxetine. The most common eye disorders were vision blurred, visual impairment, mydriasis, etc. Most of these adverse events occurred within the first 30 days of treatment. The reported incidence of severe eye disorders was 38.6% for SSRIs, with fluoxetine exhibiting the highest rate at 45.9%.

CONCLUSION

Our study demonstrates a significant association between SSRIs and the risk of eye disorders. These findings provide crucial insights for clinicians when prescribing SSRIs and underscore the need to monitor eye health in patients receiving these medications.

Antidepressant use and ovarian cancer risk: Evidence from nationwide studies with >14,000 cases from Denmark and Sweden

OBJECTIVE

Given that the evidence regarding the link between antidepressant use and ovarian cancer risk is equivocal, we investigated this research question by conducting two nationwide nested case-control studies among the Danish and Swedish populations.

METHODS

Altogether, 14,121 women with epithelial ovarian cancer (30-84 years old) (Denmark: 8976 diagnosed 2000-2019, Sweden: 5145 diagnosed 2010-2018) were randomly age-matched with 564,840 female controls (359,040 from Denmark, and 205,800 from Sweden) using risk set sampling. We used conditional logistic regression to estimate odds ratios (OR) with 95 % confidence intervals (CI) and combined the estimates based on the fixed-effect assumption. We also investigated potential effect modification by well-established risk factors for ovarian cancer.

RESULTS

Antidepressant use was associated with an overall reduced risk of ovarian cancer (OR = 0.92, 95%CI: 0.88-0.96), and that reduction was more pronounced in postmenopausal women and long-term users. The effect was most pronounced for serous ovarian tumors (OR = 0.90, 95%CI: 0.86-0.95) but was also observed in other subtypes, although not statistically significant. Among different types of antidepressants, selective serotonin reuptake inhibitors in general and citalopram in particular exhibited a noteworthy reduction in ovarian cancer risk (OR = 0.89, 95%CI: 0.82-0.96). Additionally, use of oral contraceptives and hormone replacement therapy individually modified the association between antidepressant use and ovarian cancer risk.

CONCLUSIONS

Use of an antidepressant was associated with a slight, but statistically significant, decrease in ovarian cancer risk. Given the morbidity and mortality associated with ovarian cancer, and increasing use of antidepressants, these findings may be of significance to cancer prevention and should be studied in more detail mechanistically.

Serotonin syndrome controversies: A need for consensus

Serotonin syndrome (SS) is a drug-induced clinical syndrome resulting from increased serotonergic activity in the central nervous system. Although more than seven decades have passed since the first description of SS, it is still an enigma in terms of terminology, clinical features, etiology, pathophysiology, diagnostic criteria, and therapeutic measures. The majority of SS cases have previously been reported by toxicology or psychiatry centers, particularly in people with mental illness. However, serotonergic medications are used for a variety of conditions other than mental illness. Serotonergic properties have been discovered in several new drugs, including over-the-counter medications. These days, cases are reported in non-toxicology centers, such as perioperative settings, neurology clinics, cardiology settings, gynecology settings, and pediatric clinics. Overdoses or poisonings of serotonergic agents constituted the majority of the cases observed in toxicology or psychiatry centers. Overdose or poisoning of serotonergic drugs is uncommon in other clinical settings. Patients may develop SS at therapeutic dosages. Moreover, these patients may continue to use serotonergic medications even if they develop mild to moderate SS due to several reasons. Thus, the clinical presentation (onset, severity, and clinical features) in such instances may not exactly match what toxicologists or psychiatrists observe in their respective settings. They produce considerable diversity in many aspects of SS. However, other experts discount these new developments in SS. Since SS is a potentially lethal illness, consensus is required on several concerns related to SS.

Effect of l-arginine compared to placebo on sexual function in women with major depressive disorder: a randomized controlled trial

BACKGROUND

While some evidence suggests that l-arginine may improve sexual function and alleviate depression, it has not been investigated in women with depression to assess both its effects on the depression and sexual function concurrently.

METHODS

Patients who had received a diagnosis of major depressive disorder, as determined by predetermined inclusion and exclusion criteria, were enrolled in this triple-blind clinical trial. Patients were divided into two groups: group A, received L-arginine 1 gram twice daily, and group B, received a placebo for four weeks. They were evaluated at baseline, after four and eight weeks with the Hamilton Depression Rating Scale (HDRS), and Rosen's questionnaire or Female Sexual Function Index (FSFI).

RESULTS

A decrease in the severity of depression was observed in all patients, which was determined due to Hamilton's questionnaire (P-value < 0.001). During the time in group A, FSFI increased. Based on the FSFI questionnaire, they had improvement in some domains, including the lubrication index and orgasm index, which significantly changed in the eighth week compared to the baseline (P-value < 0.05). However, these two indicators did not change statistically significantly compared to the placebo group.

CONCLUSION

L-arginine supplementation can improve sexual function, particularly lubrication and orgasm, and mood in women with depression, with minimal side effects observed. Additional research is necessary to validate these results by examining the effects of higher dosages, extended durations, and larger populations of depressed patients.

TRIAL REGISTRATION

Iranian Registry of Clinical Trial: IRCT20100127003210N26.

Antidepressant nonadherence and sexual dysfunction among young adult males: the cross-sectional YAMAN study

PURPOSE

Selective serotonin reuptake inhibitors are associated with high rates of nonadherence and sexual dysfunction, yet the correlation between these findings in young adult men is poorly characterized. We aimed to evaluate if young adult men are less willing to adhere to antidepressant treatment due to intolerable side effects, such as sexual dysfunction.

METHODS

Deidentified, compensated survey that assessed baseline demographics, PHQ-8 and GAD-7 scores, attitudes towards antidepressant medication side effects, and perceptions of antidepressant medications including selective serotonin reuptake inhibitors, bupropion, and mirtazapine.

RESULTS

From 665 delivered surveys, 505 respondents completed their survey (response rate: 76%), of which 486 were included for final analysis. After seeing common side effect profiles, our sample's willingness to take sexual function-sparing agents, such as bupropion or mirtazapine, was significantly greater than selective serotonin reuptake inhibitors (p < 0.001), with no significant difference between bupropion and mirtazapine (p = 0.263). The negative influence of erectile dysfunction and anorgasmia scored significantly higher than other common antidepressant side effects like weight gain, nausea, and dry mouth (range: p < 0.001, p = 0.043). With the exception of insomnia, participants indicated that experiencing sexual dysfunction while taking an antidepressant medication would lead to nonadherence at a significantly higher frequency than any other side effect assessed (range: p < 0.001, p = 0.005).

CONCLUSION

The risk of experiencing sexual side effects when taking antidepressants could lead young adult men to become nonadherent to these medications. Strategies to augment the effectiveness of antidepressants, such as shared decision-making and the use of sexual function-sparing agents, are critical.

Subjective experience of the environment determines serotoninergic antidepressant treatment outcome in male mice

BACKGROUND

The effects of the selective serotonin reuptake inhibitors (SSRIs), the first-line antidepressant treatment, have been proposed to be affected, at least in part, by the living environment. Since the quality of the environment depends not only on its objective features, but also on the subjective experience, we hypothesized that the latter plays a key role in determining SSRI treatment outcome.

METHODS

We chronically administered the SSRI fluoxetine to two groups of adult CD-1 male mice that reportedly show distinct subjective experiences of the environment measured as consistent and significantly different responses to the same emotional and social stimuli. These distinct socioemotional profiles were generated by rearing mice either in standard laboratory conditions (SN) or in a communal nest (CN) where three dams breed together their offspring, sharing caregiving behavior.

RESULTS

At adulthood, CN mice displayed higher levels of agonistic and anxiety-like behaviors than SN mice, indicating that they experience the environment as more socially challenging and potentially dangerous. We then administered fluoxetine, which increased offensive and anxious response in SN, while producing opposite effects in CN mice. BDNF regulation was modified by the treatment accordingly.

LIMITATIONS

Subjective experience in mice was assessed as behavioral response to the environment.

CONCLUSIONS

These results show that the subjective experience of the environment determines fluoxetine outcome. In a translational perspective, our findings suggest considering not only the objective quality, but also the subjective appraisal, of the patient's living environment for developing effective personalized therapeutic approaches in psychiatry.

Sub-chronic exposure to paroxetine disrupts ecologically relevant behaviours in fish

The functional conservation of important selective serotonin reuptake inhibitor (SSRI) targets in non-target organisms raises concerns about their potential adverse effects on the ecosystems. Although the environmental levels of SSRIs like paroxetine (PAR) have risen, the knowledge regarding the effects of long-term exposure to PAR is limited. This study investigated the impact of sub-chronic exposure (21 days) to two sub-lethal concentrations of PAR (40 and 400 μg/L) on the behaviour of adult zebrafish in different scenarios: basal activity (under dark and light conditions), stress response (evoked by sudden light transitions) and stress response recovery. A new framework was employed for the integrative study of fish's swimming performance based on their innate ability to respond to light shifts. Several swimming-associated parameters (e.g., total swimming distance, time of inactivity, swimming angles) and thigmotaxis were monitored for an integrated analysis in each scenario. Data revealed reduced swimming activity, impaired behavioural response to stress and alterations in stress recovery of PAR-exposed fish. An anxiolytic effect was particularly noticeable in fish basal swimming activity in the dark at 400 μg/L and in the behavioural response to stress (from dark to light) and stress recovery (from light to dark) for organisms exposed to 40 μg/L. The detected PAR-induced behavioural modifications suggest a disruption of brain glucocorticoid signalling that may have implications at the individual level (e.g., changing behavioural responses to predators), with potential repercussions on the population and community levels. Therefore, the applied protocol proved sensitive in detecting behavioural changes induced by PAR.

Effectiveness of antidepressants in improving the prognosis of COVID-19: A systematic review and meta-analysis

OBJECTIVE, AND MATERIAL AND METHODS

A systematic review and meta-analysis was performed to evaluate the effectiveness of antidepressants in reducing the poor evolution of COVID-19 disease (a composite variable including death, hospitalization and need for mechanical ventilation), and mortality, according the guidelines for Systematic Reviews of Interventions published by the Cochrane library.

SOURCE OF DATA

MEDLINE, EMBASE and COCHRANE LIBRARY were consulted up to February 25, 2022. Unpublished studies were searched on clinicaltrials.gov platform.

SELECTION OF STUDIES

Seven masked and unmasked, observational and experimental studies evaluating death, hospitalization and need for mechanical ventilation were selected. A second subgroup analysis with mortality variable was performed.

DATA EXTRACTION

A full risk of bias assessment was performed addressing issues such as information and confounding bias. ROB2 and Robins-I tools for randomized and no randomized studies were employed respectively. In the quantitative analysis, the risk of publication bias, heterogeneity, estimation of pooled measure and a sensitivity analysis was performed. The pooled final measure was calculated as odds ratio with its correspondent 95% confidence interval. A random effects model was used for this purpose due to the heterogeneity between included studies. Finally, a sensitivity analysis was performed to assess the robustness of final pooled measure.

RESULTS

Seven studies were finally considered to calculate the final pooled measure. The effect of intervention was OR 0.73; 95% CI 0.56-0.94.

CONCLUSIONS

The use of antidepressants, and specially SSRI could be effective for reducing the risk of poor progression of COVID-19 disease.

Melancholic features and treatment outcome to selective serotonin reuptake inhibitors in major depressive disorder: A re-analysis of the STAR*D trial

BACKGROUND

Melancholia has been positioned as a qualitatively different form of Major Depressive Disorder (MDD). Some studies have suggested that melancholic MDD patients may show lower remission when receiving treatment with Selective Serotonin Reuptake Inhibitors, but this has not yet been explored in large, representative samples of MDD.

METHODS

We used data from the STAR*D, a multisite randomized controlled trial (n = 4041). We defined melancholia status through the BA Melancholia Empirical Index, constructed using items from the Inventory of Depressive Symptomatology (IDSC). The main outcome of interest was symptomatic remission defined as a Quick Inventory of Depressive Symptoms (Clinician version) (QIDS-C) below or equal to 5. Inverse probability weighting was used to control for confounding.

RESULTS

3827 patients were eligible for this study. Melancholic patients were more likely to be unemployed, never married, to self-report an African American race, and to have a higher depressive severity. The adjusted 4-month probability of remission was 26.9 % (22.0, 45.5) for melancholic and 53.8 % (53.2, 58.5), for nonmelancholic patients. Compared with nonmelancholic, the difference in 4-month probability of remission was -26.9 % (-37.0, -15.6). Results were consistent across sensitivity analyses.

LIMITATIONS

Items from IDSC were used as a surrogate measure of the BA Melancholia Index, and extrapolation of the results to agents other than citalopram and to psychotic MDD patients requires caution.

CONCLUSIONS

Melancholic MDD patients showed lower probabilities of remission at 4-months receiving treatment with citalopram. The results of this study show how validly subtyping episodes could contribute to the personalized treatment of depression.

Pharmacogenetics of selective serotonin reuptake inhibitors (SSRI): A serotonin reuptake transporter (SERT)-based approach

Neuropsychiatric disorders are considered to be the most common cause of disability worldwide. Serotonin and its transporter is a prominent paradigm in mood disorders. Response to selective serotonin reuptake inhibitors (SSRI) is altered due to heterogeneity in the serotonin transporter gene, SLC6A4 (solute carrier family 6 member 4). The reported polymorphisms are found to be in different regions of the transporter gene: promoter region (5-HTTLPR and various single nucleotide polymorphisms within it), intron (STin2), and exon 9 (I425V). The long and short alleles of the 5-HTTLPR gene, which are prevalent among variations, may mediate differential effects. In long allelic variant carriers, an increased response to SSRI and timely recovery is due to increased availability of SERT. Whereas, SERT availability is significantly decreased in short allelic carriers, necessitating a reduction in SSRI dosage due to the increased risk of adverse drug reactions. Thus, pharmacogenetic investigations are required to understand the impact of functional variations on the efficacy and tolerability of SSRI. Identifying the carrier variants may aid in clear-decision making of the treatment regimen, aiding the approach of personalized medication.

Protocol for teen inflammation glutamate emotion research (TIGER): Toward predictors of treatment response and clinical course in depressed adolescents

Adolescent-onset depression is a prevalent and debilitating condition commonly associated with treatment refractory depression and non-response to first-line antidepressants. There are, however, no objective tests to determine who may or may not respond to antidepressants. As depressed adolescents are especially vulnerable to the lifelong consequences of ineffectively-treated depression, it is critical to identify neurobiological predictors of treatment non-response in this population. Here, we describe the scientific rationale and protocol for the Teen Inflammation Glutamate Emotion Research (TIGER) study, a prospective 18-month investigation of 160 depressed adolescents who will be assessed before and after treatment with selective serotonin reuptake inhibitors. TIGER will be using ultra-high field imaging to test the effects of acute stress and antidepressant treatment on inflammatory and glutamatergic processes hypothesized to underlie depression maintenance. Results from this work will motivate future studies testing alternative therapeutics for depressed adolescents at risk for treatment resistant depression. ClinicalTrials.gov Identifier: NCT05329441.

Protective effects of SSRI, Citalopram in mutant APP and mutant Tau expressed dorsal raphe neurons in Alzheimer's disease

Depression is among the most common neuropsychiatric comorbidities in Alzheimer's disease (AD) and other Tauopathies. Apart from its anti-depressive and anxiolytic effects, selective serotonin reuptake inhibitor (SSRI) treatment also offers intracellular modifications that may help to improve neurogenesis, reduce amyloid burden & Tau pathologies, and neuroinflammation in AD. Despite its multifaceted impact in the brain, the exact physiological and molecular mechanism by which SSRIs such as Citalopram improve neurogenesis and synaptogenesis in dementia is poorly understood. In the current study, we investigated the protective role of SSRI, Citalopram, in serotonergic, medullary raphe neurons (RN46A-B14). RN46A-B14 cells were transfected with wild-type and mutant APP and Tau cDNAs for 24 h and then treated with 20 μM Cit for 24 h. We then assessed mRNA and protein levels of pTau, total Tau, serotonin related proteins such as TPH2, SERT, and 5HTR1a, synaptic proteins and the cytoskeletal structure. We also assessed cell survival, mitochondrial respiration and mitochondrial morphology. The mutant APP and Tau transfected cells showed increased levels of serotonin related proteins and mRNA, while the mRNA and protein levels of synaptic proteins were downregulated. Citalopram treatment significantly reduced pathologically pTau level along with the serotonin related protein levels. On the other hand, there was a significant increase in the mRNA and protein levels of synaptic genes and cytoskeletal structure in the treated groups. Further, Citalopram also improved cell survival, mitochondrial respiration and mitochondrial morphology in the treated cells that express mAPP and mTau. Taken together these findings suggest Citalopram could not only be a promising therapeutic drug for treating patients with depression, but also for AD patients.

The effect of drug holidays on sexual dysfunction in men treated with selective serotonin reuptake inhibitors (SSRIs) other than fluoxetine: an 8-week open-label randomized clinical trial

INTRODUCTION

Selective serotonin reuptake inhibitors (SSRIs) are widely used for the treatment of various mental disorders. Sexual dysfunction is one of the most common side effects of SSRIs, and often leads to poor adherence and treatment discontinuation. While several strategies have been employed to manage SSRI-induced sexual dysfunction, drug holidays has not been extensively studied for this purpose. This clinical trial aims to assess the effect of drug holidays on sexual dysfunction in married men under treatment with SSRIs other than fluoxetine (as its long half-life makes drug holidays ineffective).

METHODS

This 8-week double-center, randomized, open-label, controlled trial was conducted in the outpatient clinics of Iran Psychiatric Hospital and Tehran Institute of Psychiatry, from January 2022 to March 2023. We included married men aged between18 and 50 years who had experienced sexual dysfunction during treatment with SSRIs, other than fluoxetine. The Male Sexual Health Questionnaire (MSHQ) and the 28-Question General Health Questionnaire (GHQ-28) were used for the assessment of sexual function and mental health status. The drug holidays group was instructed not to take their medications on the weekends. The control group was asked to continue their regular medication regimen without any changes. Both groups were assessed at baseline, and weeks 4 and 8.

RESULTS

Sixty-three patients were included and randomly assigned to the drug holidays group (N = 32) or the control group (N = 31). Fifty patients (25 in each group) completed the trial. Drug holidays significantly improved erection, ejaculation, satisfaction, and the overall sexual health of the participants (P < 0.001). No significant change was observed in their mental health status. No major side effects were recorded.

CONCLUSIONS

Drug holidays significantly improved the MSHQ scores in 'erection', 'ejaculation', 'satisfaction' and 'total' in married men with sexual dysfunction induced by SSRIs, other than fluoxetine, without causing any significant changes in their mental health status. Further research is needed to reach a certain conclusion.

TRIAL REGISTRATION

The trial was registered at the Iranian Registry of Clinical Trials on 2021.10.25 ( www.irct.ir ; IRCT ID: IRCT20170123032145N6) before the trial.

Structural and functional brain imaging after treatment with selective-serotonin reuptake-inhibitors in obsessive-compulsive disorder: A mini review

BACKGROUND

Obsessive-compulsive disorder (OCD) is a psychiatric disorder whose etiopathogenesis, according to various neuroimaging studies, seems to be linked to selective dysfunctions in regions within the cortico-striatal-thalamo-cortical circuit. Selective Serotonin Reuptake Inhibitors (SSRIs) are the first-line therapy for OCD but their neurobiological effects on the brain is only partially understood. Therefore, the aim of this review is to highlight structural and functional brain imaging modifications induced by SSRIs treatment.

METHODS

A literature search on PubMed, Psych-Info and Embase database was performed. Studies including patients with OCD that analyzed the effect of SSRIs through structural and functional Magnetic Resonance Imaging were selected. Seven relevant studies were considered eligible for the present review.

RESULTS

Overall, the results of the reviewed studies showed that SSRIs treatment seems to normalize structural, in terms of the white matter and gray matter volumes, and functional activity alterations observed in OCD patients, especially in regions within the prefrontal cortex and striatum.

LIMITATIONS

The poor design of the studies, the small and heterogeneous samples, differences in age, gender, illness course, comorbidities, treatment protocols and the different magnetic fields used make it difficult to generalize the results.

CONCLUSIONS

From the available evidence it emerged that SSRIs treatment has proven to be effective in normalizing brain structural and functional alterations observed in OCD patients. However, future neuroimaging investigations should focus on long-term effects of drugs on brain structure and function in OCD patients through longitudinal approaches in order to identify more effective treatments for these patients.

Exploring the human gut microbiota targets in relation to the use of contemporary antidepressants

BACKGROUND

Antidepressants, specifically selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs), are commonly prescribed for depression treatment. Animal studies have shown that antidepressants can influence gut microbiota composition and specific bacterial taxa. We aimed to investigate the association between antidepressant use and human gut microbiota composition and functional pathway.

METHODS

We collected information on antidepressant use, demographic, food patterns, and clinical characteristics through questionnaires and medical records. The gut microbiota profiles of 271 depressive patients were carried out through 16S rRNA gene sequencing. Patients were categorized based on different types of antidepressant use groups for gut microbiota comparisons. MaAsLin2 was performed to evaluate microbiota composition across groups. PICRUSt2 was used to predict microbiota functional pathways.

RESULTS

Patients taking SSRIs or SNRIs had a lower microbiota diversity. We found seven taxa abundances (Turicibacter, Barnesiella, Lachnospiraceae_ND3007_group, Romboutia, Akkermansia, Dialister, Romboutia and Fusicatenibacter) differed in patients with various types of antidepressants compared with those without antidepressant treatments (p < 0.05). Turicibacter inversely correlated with depression severity in SSRIs or SNRI users (r = -0.43, p < 0.05). Top identified pathways were related to compound fermentation and biosynthesis in microbiota function.

CONCLUSION

Antidepressant usage, especially SSRIs and SNRIs, associates with changes in gut microbiota composition and specific taxa. Given our study's preliminary cross-sectional nature, further research is warranted to comprehend the relationship between antidepressant use, treatment response, and gut microbiota, aiming to enhance therapeutic interventions in the future.