Gender differences in treatment response to sertraline versus imipramine in patients with nonmelancholic depressive disorders

Amitriptyline effectiveness in burning mouth syndrome: An in-depth case series analysis

OBJECTIVES

To assess the effectiveness of amitriptyline (AMT), and to identify the determinants of the treatment's effectiveness in patients diagnosed with burning mouth syndrome (BMS).

BACKGROUND

Treatment of BMS is challenging and no established treatment protocol is available. AMT may be an important treatment option, cout not all patients benefit from this drug. Studies assessing factors related to treatment response are valuable in improving decision-making.

MATERIALS AND METHODS

This case series study examined the medical records of all patients diagnosed with BMS at an oral medicine unit in a university hospital from 2008 to 2022. The patients were divided into responders to AMT and non-responders to AMT. Data on demographic information, comorbidities, medications, types of symptoms and oral subsites affected were collected. Descriptive and bivariate analyses were conducted to assess the association between the independent variables and the outcome, using the Chi-squared test (P < .05).

RESULTS

Three hundred and fourty-nine patients reported a burning mouth sensation, 50 of them (14.3%) being diagnosed with primary BMS. Of these, 35 were treated with AMT, and 26 (74.2%) responded significantly to AMT. All males responded to AMT, whereas only 67.9% of females responded. The mean dose of AMT among responders was 29.8 ± 12.3 mg, with most patients achieving a response with 25 mg (61.5% of patients), followed by 50 mg (23%). The concomitant use of an anticonvulsant resulted in non-response.

CONCLUSIONS

AMT may be effective in BMS management for most patients.

Chronic Stress Exposure Alters the Gut Barrier: Sex-Specific Effects on Microbiota and Jejunum Tight Junctions

Background

Major depressive disorder (MDD) is the leading cause of disability worldwide. Of individuals with MDD, 30% to 50% are unresponsive to common antidepressants, highlighting untapped causal biological mechanisms. Dysfunction in the microbiota-gut-brain axis has been implicated in MDD pathogenesis. Exposure to chronic stress disrupts blood-brain barrier integrity; still, little is known about intestinal barrier function in these conditions, particularly for the small intestine, where absorption of most foods and drugs takes place.

Methods

We investigated how chronic social or variable stress, two mouse models of depression, impact the jejunum intestinal barrier in males and females. Mice were subjected to stress paradigms followed by analysis of gene expression profiles of intestinal barrier-related targets, fecal microbial composition, and blood-based markers.

Results

Altered microbial populations and changes in gene expression of jejunum tight junctions were observed depending on the type and duration of stress, with sex-specific effects. We used machine learning to characterize in detail morphological tight junction properties, identifying a cluster of ruffled junctions in stressed animals. Junctional ruffling is associated with inflammation, so we evaluated whether lipopolysaccharide injection recapitulates stress-induced changes in the jejunum and observed profound sex differences. Finally, lipopolysaccharide-binding protein, a marker of gut barrier leakiness, was associated with stress vulnerability in mice, and translational value was confirmed on blood samples from women with MDD.

Conclusions

Our results provide evidence that chronic stress disrupts intestinal barrier homeostasis in conjunction with the manifestation of depressive-like behaviors in a sex-specific manner in mice and, possibly, in human depression.

Impact of sex on antidepressant discontinuation in groups of similar cytochrome P450 phenotypes

Introduction

Although there are studies assessing reasons for antidepressant discontinuation, little is known about the impact of sex differences or cytochrome P450 phenotypes. Our objective is to assess discontinuation rates between males and females and whether CYP450 phenotype influences discontinuation.

Methods

This is a retrospective review of patients previously enrolled in the Right Drug, Right Dose, Right Time: Using Genomic Data to Individualize Treatment database with major depressive disorder. Patients were evaluated for antidepressants trialed between January 1, 2009, and September 30, 2019. Survival analyses with competing risks were used to analyze discontinuation reasons. A Kaplan-Meier estimation method was used to assess the time to discontinuation and discontinuation rates. Analyses were also completed to assess discontinuation between men and women by phenotypic groups. All tests were two-sided, and p-values ≤ .05 were considered statistically significant.

Results

There were 620 antidepressant discontinuation events discovered from 1015 antidepressant trials included. Overall, the median time to discontinuation for males was 2.6 years and 1.9 years for females (hazard ratio [HR] 0.97 [95% confidence interval (CI): 0.80, 1.19], p = .77). The risk of discontinuation was not different between males and females in any of the phenotype groups, which was consistent in the multivariable analyses. Concomitant use of medications that inhibited or induced antidepressant metabolism increased the overall risk of discontinuation (HR 1.45, 95% CI [1.06, 1.99], p = .020) in a time-dependent analysis.

Discussion

We did not detect a significant difference in risk of antidepressant discontinuation rates between males and females even when accounting for cytochrome P450 phenotype. Future studies should account for whether medications that inhibit or induce antidepressant metabolism may be a crucial factor in antidepressant discontinuation.

Small Organic Compounds Mimicking the Effector Domain of Myristoylated Alanine-Rich C-Kinase Substrate Stimulate Female-Specific Neurite Outgrowth

Myristoylated alanine-rich C-kinase substrate (MARCKS) is a critical member of a signaling cascade that influences disease-relevant neural functions such as neural growth and plasticity. The effector domain (ED) of MARCKS interacts with the extracellular glycan polysialic acid (PSA) through the cell membrane to stimulate neurite outgrowth in cell culture. We have shown that a synthetic ED peptide improves functional recovery after spinal cord injury in female but not male mice. However, peptides themselves are unstable in therapeutic applications, so we investigated more pharmacologically relevant small organic compounds that mimic the ED peptide to maximize therapeutic potential. Using competition ELISAs, we screened small organic compound libraries to identify molecules that structurally and functionally mimic the ED peptide of MARCKS. Since we had shown sex-specific effects of MARCKS on spinal cord injury recovery, we assayed neuronal viability as well as neurite outgrowth from cultured cerebellar granule cells of female and male mice separately. We found that epigallocatechin, amiodarone, sertraline, tegaserod, and nonyloxytryptamine bind to a monoclonal antibody against the ED peptide, and compounds stimulate neurite outgrowth in cultured cerebellar granule cells of female mice only. Therefore, a search for compounds that act in males appears warranted.

Changes in Multiple microRNA Levels with Antidepressant Treatment Are Associated with Remission and Interact with Key Pathways: A Comprehensive microRNA Analysis

Individual treatment outcomes to antidepressants varies widely, yet the determinants to this difference remain elusive. MicroRNA (miRNA) gene expression regulation in major depressive disorder (MDD) has attracted interest as a biomarker. This 4-week randomized controlled trial examined changes in the plasma miRNAs that correlated with the treatment outcomes of mirtazapine (MIR) and selective serotonin reuptake inhibitor (SSRI) monotherapy. Pre- and post- treatment, we comprehensively analyzed the miRNA levels in MDD patients, and identified the gene pathways linked to these miRNAs in 46 patients. Overall, 141 miRNA levels significantly demonstrated correlations with treatment remission after 4 weeks of MIR, with miR-1237-5p showing the most robust and significant correlation after Bonferroni correction. These 141 miRNAs displayed a negative correlation with remission, indicating a decreasing trend. These miRNAs were associated with 15 pathways, including TGF-β and MAPK. Through database searches, the genes targeted by these miRNAs with the identified pathways were compared, and it was found that MAPK1, IGF1, IGF1R, and BRAF matched. Alterations in specific miRNAs levels before and after MIR treatment correlated with remission. The miRNAs mentioned in this study have not been previously reported. No other studies have investigated treatment with MIR. The identified miRNAs also correlated with depression-related genes and pathways.

Demographic and Socioeconomic Factors in Prospective Retina-Focused Clinical Trial Screening and Enrollment

Historically marginalized populations are disproportionately affected by many diseases that commonly affect the retina, yet they have been traditionally underrepresented in prospective clinical trials. This study explores whether this disparity affects the clinical trial enrollment process in the retina field and aims to inform future trial recruitment and enrollment. Age, gender, race, ethnicity, preferred language, insurance status, social security number (SSN) status, and median household income (estimated using street address and zip code) for patients referred to at least one prospective, retina-focused clinical trial at a large, urban, retina-based practice were retrospectively extracted using electronic medical records. Data were collected for the 12-month period from 1 January 2022, through 31 December 2022. Recruitment status was categorized as Enrolled, Declined, Communication (defined as patients who were not contacted, were contacted with no response, were waiting for a follow-up, or were scheduled for screening following a clinical trial referral.), and Did Not Qualify (DNQ). Univariable and multivariable analyses were used to determine significant relationships between the Enrolled and Declined groups. Among the 1477 patients, the mean age was 68.5 years old, 647 (43.9%) were male, 900 (61.7%) were White, 139 (9.5%) were Black, and 275 (18.7%) were Hispanic. The distribution of recruitment status was: 635 (43.0%) Enrolled, 232 (15.7%) Declined, 290 (19.6%) Communication, and 320 (21.7%) DNQ. In comparing socioeconomic factors between the Enrolled and Declined groups, significant odds ratios were observed for age (p < 0.02, odds ratio (OR) = 0.98, 95% confidence interval (CI) [0.97, 1.00]), and between patients who preferred English versus Spanish (p = 0.004, OR = 0.35, 95% CI [0.17, 0.72]. Significant differences between the Enrolled and Declined groups were also observed for age (p < 0.05), ethnicity (p = 0.01), preferred language (p < 0.05), insurance status (p = 0.001), and SSN status (p < 0.001). These factors may contribute to patient participation in retina-focused clinical trials. An awareness of these demographic and socioeconomic disparities may be valuable to consider when attempting to make clinical trial enrollment an equitable process for all patients, and strategies may be useful to help address these challenges.

Mirtazapine attenuates the cocaine-induced locomotor sensitization in male and female C57BL/6J and BALBA/cJ mouse

BACKGROUND

Clinical studies have described the efficacy of various therapeutic approaches. Results are inconsistent and clinical application is limited. Clinical trials have suggested that individual variability in the response to pharmacological therapies and sex affects the efficacy of some antidepressant drugs. Mouse strain-dependent variability influenced the response to antidepressant drugs. Some mouse strains respond faster and better to antidepressants than other mouse strains. We recently reported a series of preclinical studies that showed that dosing of mirtazapine, a noradrenergic and serotonergic antidepressant, in male and female Wistar rats decreased cocaine-induced locomotor activity and attenuated the induction and expression of cocaine-induced locomotor sensitization. Therefore, the aim of this study was to evaluate the mirtazapine effects, on cocaine-induced locomotor activity and cocaine-induced locomotor sensitization in male and female mice of the C57BL/6J and BALB/cJ strains, which differ in sensitivity to the cocaine motor effects and response to antidepressant drugs.

METHODS

Male and female BALB/cJ and C57BL/6J inbred mice (20-25 g) were daily dosed with 10 mg/kg of cocaine during the induction and expression of locomotor sensitization. During drug withdrawal, cocaine was withdrawn, and the groups received daily mirtazapine (30 mg/kg, i.p.) or saline. Mirtazapine was administered 30 min before cocaine. After each administration, locomotor activity for each animal was recorded for 30 min in transparent Plexiglass activity chambers.

RESULTS

Cocaine-induced locomotor activity were greater in C57BL/6J strain mice than BALB/cJ strain mice during the induction and expression phase of locomotor sensitization. The female mice of both strains showed a higher cocaine locomotor response than males and mirtazapine significantly decreased cocaine-induced locomotor activity, as well as the induction and expression of locomotor sensitization, regardless of mouse strain or sex.

CONCLUSION

The results suggest mirtazapine may be considered an effective therapeutic option to treat cocaine use disorder in men and women with very diverse genetic backgrounds.

The Response of the Rodent Gut Microbiome to Broad-Spectrum Antibiotics Is Different in Males and Females

Gut microbiome composition is different in males and females, but sex is rarely considered when prescribing antibiotics, and sex-based differences in gut microbiome recovery following antibiotic treatment are poorly understood. Here, we compared the effects of broad-spectrum antibiotics on both the stool and small bowel microbiomes in male and female rats. Adult male and female Sprague Dawley rats were exposed to a multi-drug antibiotic cocktail for 8 days, or remained unexposed as controls. Following cessation of antibiotics, rats were monitored for an additional 13-day recovery period prior to euthanasia. Baseline stool microbiome composition was similar in males and females. By antibiotic exposure day 8 (AbxD8), exposed male rats exhibited greater loss of stool microbial diversity compared to exposed females, and the relative abundance (RA) of numerous taxa were significantly different in exposed males vs. exposed females. Specifically, RA of phylum Proteobacteria and genera Lactobacillus, Sutterella, Akkermansia, and Serratia were higher in exposed males vs. exposed females, whereas RA of phyla Firmicutes and Actinobacteria and genera Turicibacter and Enterococcus were lower. By 13 days post antibiotics cessation (PAbxD13), the stool RA of these and other taxa remained significantly different from baseline, and also remained significantly different between exposed males and exposed females. RA of phyla Firmicutes and Actinobacteria and genus Enterococcus remained lower in exposed males vs. exposed females, and genus Sutterella remained higher. However, RA of phylum Proteobacteria and genus Akkermansia were now also lower in exposed males vs. females, whereas RA of phylum Bacteroidetes and genus Turicibacter were now higher in exposed males. Further, the small bowel microbiome of exposed rats on PAbxD13 was also significantly different from unexposed controls, with higher RA of Firmicutes, Turicibacter and Parabacteroides in exposed males vs. females, and lower RA of Bacteroidetes, Proteobacteria, Actinobacteria, Oscillospira, Sutterella, and Akkermansia in exposed males vs. females. These findings indicate that broad-spectrum antibiotics have significant and sex-specific effects on gut microbial populations in both stool and the small bowel, and that the recovery of gut microbial populations following exposure to broad-spectrum antibiotics also differs between sexes. These findings may have clinical implications for the way antibiotics are prescribed.

Sex differences in ketamine's therapeutic effects for mood disorders: A systematic review

Replicated clinical trials have demonstrated rapid and robust antidepressant effects with ketamine in treatment resistant mood disorders. Sex (biological) and gender differences in therapeutic effects for any new intervention is an important consideration, however, the differential efficacy, safety and tolerability of ketamine in males versus females remains underexplored. The objective of the present systematic review is to identify and qualitatively synthesize all published clinical studies relevant to the sex differential effects of ketamine for mood disorders. A systematic search of PubMed, Medline, and PsycInfo from inception until January 20, 2021, yielded 27 reports including 1715 patients (742 males and 973 females) that met inclusion criteria. Results from the vast majority of studies (88.8%) do not support significant sex differences in antidepressant response, tolerability or safety of ketamine. Nine (33.3%) of the reports included a bioanalytical component in the analysis and only one reported on sex differences. Evidence from the present review does not support clinically or statistically significant sex differences in therapeutic effects with ketamine. Nevertheless, future studies should continue to consider sex and biological sex differences in study design and data analytic plans.

Sex-Related Differences in Pharmacological Response to CNS Drugs: A Narrative Review

In the last decades, both animal and human studies have neglected female subjects with the aim of evading a theorized intricacy of feminine hormonal status. However, clinical experience proves that pharmacological response may vary between the two sexes since pathophysiological dissimilarities between men and women significantly influence the pharmacokinetics and pharmacodynamics of drugs. Sex-related differences in central nervous system (CNS) medication are particularly challenging to assess due to the complexity of disease manifestation, drugs’ intricate mechanisms of action, and lack of trustworthy means of evaluating the clinical response to medication. Although many studies showed contrary results, it appears to be a general tendency towards a certain sex-related difference in each pharmacological class. Broadly, opioids seem to produce better analgesia in women especially when they are administered for a prolonged period of time. On the other hand, respiratory and gastrointestinal adverse drug reactions (ADRs) following morphine therapy are more prevalent among female patients. Regarding antidepressants, studies suggest that males might respond better to tricyclic antidepressants (TCAs), whereas females prefer selective serotonin reuptake inhibitors (SSRI), probably due to their tolerance to particular ADRs. In general, studies missed spotting any significant sex-related differences in the therapeutic effect of antiepileptic drugs (AED), but ADRs have sex variations in conjunction with sex hormones’ metabolism. On the subject of antipsychotic therapy, women appear to have a superior response to this pharmacological class, although there are also studies claiming the opposite. However, it seems that reported sex-related differences regarding ADRs are steadier: women are more at risk of developing various side effects, such as metabolic dysfunctions, cardiovascular disorders, and hyperprolactinemia. Taking all of the above into account, it seems that response to CNS drugs might be occasionally influenced by sex as a biological variable. Nonetheless, although for each pharmacological class, studies generally converge to a certain pattern, opposite outcomes are standing in the way of a clear consensus. Hence, the fact that so many studies are yielding conflicting results emphasizes once again the need to address sex-related differences in pharmacological response to drugs.

Let's talk about sex: Differences in drug therapy in males and females

Professor Henry Higgins in My Fair Lady said, 'Why can't a woman be more like a man?' Perhaps unintended, such narration extends to the reality of current drug development. A clear sex-gap exists in pharmaceutical research spanning from preclinical studies, clinical trials to post-marketing surveillance with a bias towards males. Consequently, women experience adverse drug reactions from approved drug products more often than men. Distinct differences in pharmaceutical response across drug classes and the lack of understanding of disease pathophysiology also exists between the sexes, often leading to suboptimal drug therapy in women. This review explores the influence of sex as a biological variable in drug delivery, pharmacokinetic response and overall efficacy in the context of pharmaceutical research and practice in the clinic. Prospective recommendations are provided to guide researchers towards the consideration of sex differences in methodologies and analyses. The promotion of disaggregating data according to sex to strengthen scientific rigour, encouraging innovation through the personalisation of medicines and adopting machine learning algorithms is vital for optimised drug development in the sexes and population health equity.

Systematic review of gender bias in vortioxetine clinical trials

This paper evaluates gender bias in the published clinical trials of Vortioxetine. We conducted a systematic review of controlled clinical trials of Vortioxetine for the treatment of depression. The literature search was performed using MEDLINE and following the corresponding international recommendations. We identified 42 articles, of which 23 were included. The proportion of women ranged from 47%-75% and the percentage of women included in the 10,404 total patients sample was 65%. The separate analysis of the main variable between the subpopulations of men and women was only carried out in 3/23 publications included. In contrast, 6/23 trials analyzed secondary variables separated by sex. No trials discussed the results separately by sex. The proportion of women included was slightly higher than that in clinical trials of other antidepressants. However, the analysis of the main result or secondary variables by sex, as well as discussing the results separately by sex, are scarce. This gives rise to gender bias in these works.

Effect of the morphine/heroin vaccine on opioid and non-opioid drug-induced antinociception in mice

Pain is a common symptom in patients with opioid use disorder (OUD), which increases synthetic and illicit synthetic opioid abuse and even fatalities due to opioid overdose. Many FDA-approved drugs are available for the treatment of OUD, however, the use of these medications is limited, mainly due to the development of various side effects. Active vaccination is a new therapeutic approach but the resulting antibodies may compromise the use and efficiency of opioid and non-opioid drugs. In this study, we evaluated whether the antibodies produced by the morphine/heroin vaccine (M-TT) would alter the antinociceptive effects of opioid and non-opioid drugs. Female Balb-c mice were immunized with the M-TT vaccine. A solid-phase antibody-capture ELISA was used for monitoring antibody titer responses after each booster dose in vaccinated animals, followed by tail-flick testing. This study found that the M-TT vaccine did not affect the antinociception induced by different doses of morphine or the ability of non-opioid and synthetic opioid drugs to decrease thermal pain. Moreover, the combination of vaccination and naloxone increased the time-course of morphine antagonism relative to either vaccination or naloxone alone. These results suggest that the antibody titers generated by the M-TT vaccine 1) are capable of reducing morphine-induced antinociception and 2) are selective enough not to alter antinociception induced by non-opioid or synthetic drugs. These characteristics support its potential as a treatment agent for patients with symptoms of pain comorbid to OUD.

Mirtazapine reduces the expression of cocaine-induced locomotor sensitization in male and female Wistar rats

BACKGROUND

Epidemiological studies have described that women are more vulnerable to the reinforcing effects of cocaine. In animals, the findings are similar: female rats show higher levels of cocaine self-administration and increased cocaine-induced locomotor activity. In contrast, women with depression respond better to treatment with antidepressants, however their therapeutic response to tetracyclic antidepressants is lower. Several studies have shown that mirtazapine-a tetracyclic antidepressant-decreases the behavioral effects of cocaine in male rats. The objective of this study was to evaluate the efficacy of daily dosing of mirtazapine on cocaine-induced locomotor activity and sensitization in naive female rats compared to male rats.

METHODS

Male and female Wistar rats were daily dosed with 10 mg/kg of cocaine. During extinction, cocaine was withdrawn and the groups received daily mirtazapine (30 mg/kg, i.p.) or saline. Tamoxifen was administered during the antagonism phase. After each administration, locomotor activity for each animal was recorded for 30 min in transparent Plexiglass activity chambers.

RESULTS

In this study, a higher cocaine locomotor response was found in females than in males and the mirtazapine was equally effective in decreasing cocaine-induced locomotor activity and the expression of locomotor sensitization in male and female rats. In addition, co-administration of mirtazapine and tamoxifen enhanced the efficacy of mirtazapine in female rats.

CONCLUSION

The results suggest that mirtazapine may be considered an effective therapeutic option for the treatment of cocaine use disorder in men and women.

What do we know about sex differences in depression: A review of animal models and potential mechanisms

Clinical studies have shown that women are more susceptible to depression than men. Sex differences in depression have been associated with social, cultural, as well as biological factors. In spite of extensive preclinical studies in animal models for depression that have been used for understanding the mechanisms of the disease as well as for new drug development, a substantive lack of attention on sex-specific phenotypes in depression might mask the effect of sex on the outcome. In this review article, we summarize findings on the influence of sex on behavior in the most commonly used animal models for depression. We also discuss the potential underlying mechanisms of such sex-dependent variation in the phenotype, particularly in the neuroendocrine system.

Sex Differences in Antidepressant Effect of Sertraline in Transgenic Mouse Models

The main purpose of this study is to explore sex differences in the antidepressant effect of sertraline in genetic knockout or overexpression estrogen-synthesizing enzyme aromatase (Ar) gene mouse models in the forced swim test (FST). Our results demonstrated a significant reduction of depression-like behavior in the mice with overexpression of brain aromatase (Thy1-Ar) compared to sex- and age-matched Ar^+/− mice or wild type control mice. Using HPLC analysis, we also found an association between the brain estrogen-related antidepressive behavior and the regulation of serotonin (5-HT) system. Interestingly, a single dose administration of sertraline (10 mg/kg, i.p.) induced reduction of immobility time was found in all genotypes, except male Ar^+/− mice. While the underlying mechanisms of sex-specific response on antidepressive effect of sertraline remain to be investigated, our data showed that female mice appear to be more sensitive to sertraline-induced changes of 5-HT system than male mice in the prefrontal cortex (PFC) and the hippocampus (HPC). Further investigation of sex-specific effect of brain estrogen on antidepressant is needed.

Women's Psychiatry

Brain disorders and mental diseases, in particular, are common and considered as a top global health challenge for the twenty-first century. Interestingly, women suffer more frequently from mental disorders than men. Moreover, women may respond to psychotropic drugs differently than men, and, through their lifespan, they endure sex-orientated social stressors. In this chapter, we present how women may differ in the development and manifestation of mental health issues and how they differ from men in pharmacokinetics and pharmacodynamics. We discuss issues in clinical trials regarding women participation, issues in the use of psychotropic medications in pregnancy, and challenges that psychiatry faces as a result of the wider use of contraceptives, of childbearing at older age, and of menopause. Such issues, among others, demand further women-oriented psychiatric research that can improve the care for women during the course of their lives. Indeed, despite all these known sex differences, psychiatry for both men and women patients uses the same approach. Thereby, a modified paradigm for women's psychiatry, which takes into account all these differences, emerges as a necessity, and psychiatric research should take more vigorously into account sex differences.

Inflaming sex differences in mood disorders

Men and women often experience different symptoms or rates of occurrence for a variety of mood disorders. Many of the symptoms of mood disorders overlap with autoimmune disorders, which also have a higher prevalence in women. There is a growing interest in exploring the immune system to provide biomarkers for diagnosis of mood disorders, along with new targets for developing treatments. This review examines known sex differences in the immune system and their relationship to mood disorders. We focus on immune alterations associated with unipolar depression, bipolar depression, and anxiety disorders. We describe work from both basic and clinical research examining potential immune mechanisms thought to contribute to stress susceptibility and associated mood disorders. We propose that sex and age are important, intertwined factors that need to be included in future experimental designs if we are going to harness the power of the immune system to develop a new wave of treatments for mood disorders.

Deciphering sex differences in the immune system and depression

Certain mood disorders and autoimmune diseases are predominately female diseases but we do not know why. Here, we explore the relationship between depression and the immune system from a sex-based perspective. This review characterizes sex differences in the immune system in health and disease. We explore the contribution of gonadal and stress hormones to immune function at the cellular and molecular level in the brain and body. We propose hormonal and genetic sex specific immune mechanisms that may contribute to the etiology of mood disorders.

Hormonal Regulation of Hippocampal Neurogenesis: Implications for Depression and Exercise

Adult hippocampal neurogenesis exists in all mammalian species, including humans, and although there has been considerable research investigating the function and regulation of neurogenesis, there remain many open questions surrounding the complexity of this phenomenon. This stems partially from the fact that neurogenesis is a multistage process that involves proliferation, differentiation, migration, survival, and eventual integration of new cells into the existing hippocampal circuitry, each of which can be independently influenced. The function of adult neurogenesis in the hippocampus is related to stress regulation, behavioral efficacy of antidepressants, long-term spatial memory, forgetting, and pattern separation. Steroid hormones influence the regulation of hippocampal neurogenesis, stress regulation, and cognition and differently in males and females. In this chapter, we will briefly tap into the complex network of steroid hormone modulation of neurogenesis in the hippocampus with specific emphasis on stress, testosterone, and estrogen. We examine the possible role of neurogenesis in the etiology of depression and influencing treatment by examining the influence of both pharmacological (selective serotonin reuptake inhibitors, tricyclic antidepressants) treatments and non-pharmacological (exercise) remedies.

Preclinical sex differences in depression and antidepressant response: Implications for clinical research

Women suffer from depression and anxiety disorders more often than men, and as a result they receive antidepressants to a greater extent. Sex differences in antidepressant response in humans have been modestly studied, and results have been controversial. At the same time, preclinical studies on animal models of depression and antidepressant response have provided insights with regard to sex differences that could be useful for the design and interpretation of future clinical trials. This Mini-Review discusses such sex-differentiated findings with regard to the presentation of depression, endophenotypes, and antidepressant response. In particular, men and women differ in symptomatology of depression, and animal models of depression have revealed sex differences in behavioral indices. However, although in experimental studies behavioral indices and models are adjusted to identify sex differences properly, this is not the case in the use of depression rating scales in clinical studies. Accordingly, preclinical studies highlight the importance of sex differences at the baseline behavioral response and the underlying mechanisms that often converge after antidepressant treatment. This is also a neglected issue in human studies. Finally, preclinical research suggests that, in the quest for potential biomarkers for depression, sex should be an important factor to consider. Careful consideration of sex differences in preclinical research could facilitate and ameliorate the design and quality of clinical studies for disease biomarkers and novel fast-acting antidepressants that are so essential for both men and women suffering from depression. © 2016 Wiley Periodicals, Inc.

Sex differences in the psychopharmacological treatment of depression

Although a number of studies have observed that females respond better to serotonergic antidepressants than males and that postmenopausal females have a diminished response to antidepressants compared with younger females, there are also studies that conflict with both of these findings, making any generalizations regarding sex differences difficult to make. Sex variance in antidepressant efficacy and pharmacokinetics profiles have been attributed to sex-based physiological differences, behavioral differences, related disorders, and sex-specific conditions, including pregnancy and menopause. This paper will review the history and current research on sex effects of antidepressant treatment.

Effect of Abrupt Discontinuation of Antidepressants in Critically Ill Hospitalized Adults

OBJECTIVES

To determine whether discontinuation of chronic antidepressant therapy is associated with a higher risk of antidepressant discontinuation syndrome (ADS) symptoms in patients admitted to the intensive care unit (ICU) when compared with those who were continued on therapy and to identify factors associated with increased risk of ADS in this population.

DESIGN

Single-center retrospective observational cohort study.

SETTING

ICUs in a tertiary care hospital.

PATIENTS

A total of 106 adult patients, admitted to the ICU between September 2013 and August 2014, who had a length of stay of 72 hours or longer and who were receiving chronic selective serotonin inhibitors (SSRIs) or serotonin-norepinephrine reuptake inhibitors (SNRIs) before admission.

MEASUREMENTS AND MAIN RESULTS

Patients were classified as continued or discontinued from therapy based on initiation of home SSRI/SNRI therapy within 48 hours of admission. The primary end point was incidence of ADS symptoms. Type of symptoms, receipt of symptom-related therapies, and length of stay were also assessed. Sequential logistic regression analysis was used to determine the impact of discontinuation while controlling for other risk factors. Therapy was discontinued in 38.7% of patients. The risk of developing ADS symptoms was higher in discontinued patients (unadjusted odds ratio [OR] 2.6, 95% confidence interval [CI] 1.12-6.07, p=0.024). After adjusting for covariates, the odds of ADS increased (adjusted OR 3.8, 95% CI 1.3-11.7, p=0.018). Female sex was associated with an increase in risk of ADS (OR 3.4, 95% CI 1.2-10.0, p=0.026). Affective symptoms were the most prevalent type reported (34.1% vs 10.8%, p=0.005). Use of symptom-related therapies and length of stay did not differ between groups.

CONCLUSION

Abrupt discontinuation of SSRI/SNRI therapy increases the risk of ADS symptoms in critically ill patients, particularly in females. These results underscore the importance of continuation of home antidepressant therapy even in the setting of critical illness.

Lurasidone in post-menopausal females with major depressive disorder with mixed features: Post-hoc analysis of a placebo-controlled trial

BACKGROUND

Several studies have found that depressed, post-menopausal females may respond differently to antidepressants compared to pre-menopausal females. The atypical antipsychotic lurasidone, whose mechanism of action differs from SSRIs and other standard antidepressants, was shown in a 6-week randomized, flexible-dose, placebo-controlled study (n=209), to be effective in treating major depressive disorder (MDD) with mixed features (subthreshold hypomanic symptoms). This post-hoc analysis assessed the efficacy of lurasidone in this study by menopausal status.

METHODS

The main outcome measure for this post-hoc analysis was change in MADRS score from baseline to week 6 endpoint for two lurasidone-treated subgroups: presumptive pre-menopausal (<52years) and presumptive post-menopausal (≥52years) patients, compared to placebo treatment, using a mixed-model for repeated-measures analysis, and calculation of the effect size for each subgroup. Additional efficacy assessments included the CGI-S, HAM-A and YMRS. An exploratory analysis was also conducted removing presumptive peri-menopausal women (ages 45-51years) to allow for clearer definition of pre- and post-menopausal status.

RESULTS

A total of 56 lurasidone-treated and 47 placebo-treated pre-menopausal females, and 17 lurasidone-treated and 25 placebo-treated post-menopausal females were available from the larger study for comparison on key outcome measures. The pre- and post-menopausal subgroups had similar demographic and clinical characteristics at study baseline (other than age), including number of past major depressive episodes as well as depressive and manic symptom severity. Mean daily lurasidone dose was similar for each subgroup during the study. Both the primary and exploratory analyses showed that both lurasidone-treated post-menopausal and pre-menopausal females responded significantly compared to placebo (p=0.016 or less) on the MADRS, and that post-menopausal patients had a numerically larger response (effect size=0.96) than pre-menopausal patients (effect size=0.64). All other secondary outcome measures for lurasidone compared with placebo treatment were significant (p=0.045 or less) for both subgroups.

CONCLUSIONS

In this post-hoc analysis, lurasidone was found to be effective in treating post-menopausal MDD patients with mixed features (subthreshold hypomanic symptoms).

Integrative Analysis of Sex-Specific microRNA Networks Following Stress in Mouse Nucleus Accumbens

Adult women are twice as likely as men to suffer from affective and anxiety disorders, although the mechanisms underlying heightened female stress susceptibility are incompletely understood. Recent findings in mouse Nucleus Accumbens (NAc) suggest a role for DNA methylation-driven sex differences in genome-wide transcriptional profiles. However, the role of another epigenetic process-microRNA (miR) regulation-has yet to be explored. We exposed male and female mice to Subchronic Variable Stress (SCVS), a stress paradigm that produces depression-like behavior in female, but not male, mice, and performed next generation mRNA and miR sequencing on NAc tissue. We applied a combination of differential expression, miR-mRNA network and functional enrichment analyses to characterize the transcriptional and post-transcriptional landscape of sex differences in NAc stress response. We find that male and female mice exhibit largely non-overlapping miR and mRNA profiles following SCVS. The two sexes also show enrichment of different molecular pathways and functions. Collectively, our results suggest that males and females mount fundamentally different transcriptional and post-transcriptional responses to SCVS and engage sex-specific molecular processes following stress. These findings have implications for the pathophysiology and treatment of stress-related disorders in women.

Systematic Analysis of Adverse Event Reports for Sex Differences in Adverse Drug Events

Increasing evidence has shown that sex differences exist in Adverse Drug Events (ADEs). Identifying those sex differences in ADEs could reduce the experience of ADEs for patients and could be conducive to the development of personalized medicine. In this study, we analyzed a normalized US Food and Drug Administration Adverse Event Reporting System (FAERS). Chi-squared test was conducted to discover which treatment regimens or drugs had sex differences in adverse events. Moreover, reporting odds ratio (ROR) and P value were calculated to quantify the signals of sex differences for specific drug-event combinations. Logistic regression was applied to remove the confounding effect from the baseline sex difference of the events. We detected among 668 drugs of the most frequent 20 treatment regimens in the United States, 307 drugs have sex differences in ADEs. In addition, we identified 736 unique drug-event combinations with significant sex differences. After removing the confounding effect from the baseline sex difference of the events, there are 266 combinations remained. Drug labels or previous studies verified some of them while others warrant further investigation.

Testosterone has antidepressant-like efficacy and facilitates imipramine-induced neuroplasticity in male rats exposed to chronic unpredictable stress

Hypogonadal men are more likely to develop depression, while testosterone supplementation shows antidepressant-like effects in hypogonadal men and facilitates antidepressant efficacy. Depression is associated with hypothalamic-pituitary-adrenal (HPA) axis hyperactivity and testosterone exerts suppressive effects on the HPA axis. The hippocampus also plays a role in the feedback regulation of the HPA axis, and depressed patients show reduced hippocampal neuroplasticity. We assessed the antidepressant-like effects of testosterone with, or without, imipramine on behavioral and neural endophenotypes of depression in a chronic unpredictable stress (CUS) model of depression. A 21-day CUS protocol was used on gonadectomized male Sprague-Dawley rats treated with vehicle, 1mg of testosterone propionate, 10mg/kg of imipramine, or testosterone and imipramine in tandem. Testosterone treatment reduced novelty-induced hypophagia following CUS exposure, but not under non-stress conditions, representing state-dependent effects. Further, testosterone increased the latency to immobility in the forced swim test (FST), reduced basal corticosterone, and reduced adrenal mass in CUS-exposed rats. Testosterone also facilitated the effects of imipramine by reducing the latency to immobility in the FST and increasing sucrose preference. Testosterone treatment had no significant effect on neurogenesis, though the combination of testosterone and imipramine increased PSA-NCAM expression in the ventral dentate gyrus. These findings demonstrate the antidepressant- and anxiolytic-like effects of testosterone within a CUS model of depression, and provide insight into the mechanism of action, which appears to be independent of enhanced hippocampal neurogenesis.

Evidence-based guidelines for treating depressive disorders with antidepressants: A revision of the 2008 British Association for Psychopharmacology guidelines

A revision of the 2008 British Association for Psychopharmacology evidence-based guidelines for treating depressive disorders with antidepressants was undertaken in order to incorporate new evidence and to update the recommendations where appropriate. A consensus meeting involving experts in depressive disorders and their management was held in September 2012. Key areas in treating depression were reviewed and the strength of evidence and clinical implications were considered. The guidelines were then revised after extensive feedback from participants and interested parties. A literature review is provided which identifies the quality of evidence upon which the recommendations are made. These guidelines cover the nature and detection of depressive disorders, acute treatment with antidepressant drugs, choice of drug versus alternative treatment, practical issues in prescribing and management, next-step treatment, relapse prevention, treatment of relapse and stopping treatment. Significant changes since the last guidelines were published in 2008 include the availability of new antidepressant treatment options, improved evidence supporting certain augmentation strategies (drug and non-drug), management of potential long-term side effects, updated guidance for prescribing in elderly and adolescent populations and updated guidance for optimal prescribing. Suggestions for future research priorities are also made.

Gender differences in the treatment of patients with bipolar disorder: a study of 7354 patients

BACKGROUND

Gender differences in treatment that are not supported by empirical evidence have been reported in several areas of medicine. Here, the aim was to evaluate potential gender differences in the treatment for bipolar disorder.

METHODS

Data was collected from the Swedish National Quality Assurance Register for bipolar disorder (BipoläR). Baseline registrations from the period 2004-2011 of 7354 patients were analyzed. Multiple logistic regression analysis was used to study the impact of gender on interventions.

RESULTS

Women were more often treated with antidepressants, lamotrigine, electroconvulsive therapy, benzodiazepines, and psychotherapy. Men were more often treated with lithium. There were no gender differences in treatment with mood stabilizers as a group, neuroleptics, or valproate. Subgroup analyses revealed that ECT was more common in women only in the bipolar I subgroup. Contrariwise, lamotrigine was more common in women only in the bipolar II subgroup.

LIMITATIONS

As BipoläR contains data on outpatient treatment of persons with bipolar disorder in Sweden, it is unclear if these findings translate to inpatient care and to outpatient treatment in other countries.

CONCLUSIONS

Men and women with bipolar disorder receive different treatments in routine clinical settings in Sweden. Gender differences in level of functioning, bipolar subtype, or severity of bipolar disorder could not explain the higher prevalence of pharmacological treatment, electroconvulsive therapy, and psychotherapy in women. Our results suggest that clinicians׳ treatment decisions are to some extent unduly influenced by patients׳ gender.

Sex differences in the pharmacokinetics of antidepressants: influence of female sex hormones and oral contraceptives

Women are twice as likely to develop depression as men. Moreover, the symptoms they experience also show sex differences: women tend to develop depression at an earlier age and show more severe symptoms than men. Likewise, the response to antidepressant pharmacotherapy appears to have sex differences. These differences can partially be explained by differences in pharmacokinetic properties (i.e., absorption, distribution, metabolism, and excretion) of drugs in males and females. More recent research has shown that sex hormones may influence all these previously named pharmacokinetic processes. As concentrations of sex hormones vary throughout the female lifespan, these hormonal variations can have effects on therapeutic responses to antidepressants as well as the occurrence of adverse events. The purpose of this paper is therefore to review the literature reporting on the effects of female sex hormones on the pharmacokinetics of antidepressants and to discuss and evaluate the implications of changes in levels of sex hormones throughout life for the treatment of depression.

Gender differences in genetic mouse models evaluated for depressive-like and antidepressant behavior

Depression is a mental disease that affects complex cognitive and emotional functions. It is believed that depression is twice as prevalent in women as in men. This phenomenon may influence the response to various antidepressant therapies, and these differences are still underestimated in clinical treatment. Nevertheless, most of the current findings are based on studies on male animal models, and relatively few of these studies take possible gender differences into consideration. Advancements in genetic engineering over the last two decades have introduced many transgenic lines that have been screened to study the pathomechanisms of depression. In this mini-review, we provide a compendious list of genetically altered mice that underwent tests for depressive-like or antidepressant behavior and determine if and how the gender factor was analyzed in their evaluation. Furthermore, we compile the gender differences in response to antidepressant treatment. On the basis of these analyses, we conclude that in many cases, gender variability is neglected or not taken into consideration in the presented results. We note the necessity of discussing this issue in the phenotypic characterization of transgenic mice, which seems to be particularly important while modeling mental diseases.

A gender analysis of the study of pharmacotherapy of psychotic depression (STOP-PD): gender and age as predictors of response and treatment-associated changes in body mass index and metabolic measures

BACKGROUND

Gender differences exist in psychiatric disorders; however, gender has not been well studied in psychotic depression. This analysis of the largest clinical trial in psychotic depression examined the effects of age and gender on clinical characteristics and predictors of treatment outcome and treatment-associated changes in body mass index (BMI) and metabolic measures.

METHOD

Secondary analyses were performed on data from 259 subjects with major depressive disorder with psychotic features (DSM-IV-TR) aged 18-93 years in the double-blind randomized controlled trial of olanzapine plus sertraline versus olanzapine plus placebo for psychotic depression (Study of Pharmacotherapy of Psychotic Depression). Sociodemographic factors, clinical characteristics, treatment outcome, and treatment-associated changes in BMI and metabolic measures were analyzed by gender and age. Subjects were enrolled from December 2002 to June 2007.

RESULTS

Female gender was associated with divorced (χ(2)(1) = 5.3, P = .03) or widowed (χ(2)(1) = 8.1, P ≤ .01) marital status. Comorbid anxiety disorders were more common in women than in men (χ(2)(1) = 4.9, P = .03). Hallucinations (χ(2)(1) = 7.8, P = .005) and delusions with disorganization (t(257) = -2.10, P = .04) were significantly associated with female gender, as were higher cholesterol measures (χ(2)(1) = 7.15, P = .008). There were no significant interactions between treatment and gender in terms of change in BMI. Gender was not associated with treatment response.

DISCUSSION

This study is the first analysis of gender and age as predictors of treatment outcome and treatment-associated changes in BMI and metabolic adverse effects in psychotic depression. Gender differences exist in patients with psychotic depression, most notably with regard to the presence of hallucinations. Female gender was associated with metabolic measures. Future studies with larger sample sizes may detect small gender differences in treatment outcome and treatment-associated changes in BMI and metabolic measures in psychotic depression.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00056472.

Sex- and endocrine-stage-differences in middle-aged rats in an animal model of OCD

Various clinical studies suggest that many features of OCD are influenced by sex, age and fluctuations in hormonal levels. Animal models have confirmed these differences, and suggest they are mediated by the serotonergic system. We compared the perseveration behavior in a T-maze after the administration of the 5-HT1A agonist, 8-OH-DPAT (2.0 mg/kg) and the preventive action of subchronic fluoxetine (10 mg/kg, 3 times) in middle-aged (11-14 months) males and female rats in two endocrine states: irregular cycles (tested in diestrus) or persistent diestrus. After 8-OH-DPAT, females with persistent diestrus presented higher perseveration scores than males and females with irregular cycles. Fluoxetine produced an anticompulsive-like effect only in females with persistent diestrus. Females in persistent diestrus showed higher estradiol levels than those in irregular cycles or males. In all groups 8-OH-DPAT increased ambulation and fluoxetine did not modify this action. In males, the combined administration of fluoxetine and 8-OH-DPAT impaired motor coordination. Data are discussed on the basis of estradiol levels and sex differences.

Pharmacokinetics and pharmacodynamics of psychotropic drugs: effect of sex

Data on the specific effects of sex on pharmacokinetics, as well as tolerability, safety, and efficacy of psychotropic medications are still meager, mainly because only recently sex-related issues have attracted a certain degree of interest within the pharmacological domain. Therefore, with the present study, we aimed to provide a comprehensive review of the literature on this topic, through careful MEDLINE and PubMed searches of the years 1990-2012. Generally, data on pharmacokinetics are more consistent and numerous than those on pharmacodynamics. Sex-related differences have been reported for several parameters that influence pharmacokinetics, such as gastric acidity, intestinal motility, body weight and composition, blood volume, liver enzymes (mainly the cytochrome P450), or renal excretion, which may alter plasma drug levels. Sex-related peculiarities may also account for a different sensitivity of men and women to side effects and toxicity of psychotropic drugs. Further, some differences in drug response, mainly to antipsychotics and antidepressants, have been described. Further studies are, however, necessary to explore more thoroughly the impact of sex on the pharmacokinetics and pharmacodynamics of psychotropic drugs, in order to reach the most appropriate and tailored prescription for each patient.

Influence of sociodemographic and socioeconomic features on treatment outcome in RCTs versus daily psychiatric practice

PURPOSE

Sociodemographic and socioeconomic characteristics of participants in antidepressant and psychotherapy efficacy trials (AETs and PETs) for major depressive disorder (MDD) may limit the generalizability of the results. We compared trial participants with daily practice patients. We subsequently assessed the influence of socio-demographic and socioeconomic status on treatment outcome in daily practice.

METHODS

Data on daily practice patients were derived through routine outcome monitoring (ROM). We included 626 patients with MDD according to the MINIplus. Distributions of age, gender, race, marital status and employment status were compared with participants in 63 selected AETs and PETs. Influence of these features on treatment outcome was explored through multivariate regression analysis.

RESULTS

Trial participants were older, more often male (diff. 4 %, p = 0.05), white (diff. 4 %, p < 0.001) and not married (diff. 7 %, p = 0.003). Although significant, most differences were relatively small. However, the difference in employment status was striking: 34 % of the ROM patients were currently working versus 68 % of the trial participants (diff. 34 %, p < 0.001). Being employed contributed to a positive treatment outcome: OR 1.8 for response [50 % reduction of Montgomery Asberg Rating Scale for Depression (MADRS)], OR 1.9 for remission (MADRS ≤10).

CONCLUSIONS

Employment status should be taken into account while interpreting results from randomized controlled trials and as predictor of treatment success in daily practice.

Impact of reproductive status and age on response of depressed women to cognitive therapy

OBJECTIVE

Previous research suggests that reproductive hormones are potential affective modulators in mood disorders and may influence response to antidepressant medications. To our knowledge, there are no data on relationships between hormonal status and response to psychotherapy for recurrent major depressive disorder (MDD).

METHODS

At two sites, female outpatients (n=353), aged 18-70, with recurrent MDD received 12-14 weeks of cognitive therapy (CT). Menopausal status and age were based on self-report. In the parent study, nonresponse to therapy was defined as persistence of a major depressive episode (MDE) as defined by the DSM-IV or a final Hamilton Rating Scale for Depression-17-Item (HRSD(17)) score of ≥ 12 or both. More traditional definitions of response (at least a 50% reduction in pretreatment HRSD(17)) and remission (a final HRSD(17) ≤ 6) were also examined.

RESULTS

Controlling for pretreatment HRSD(17) scores, there were no significant differences found in the rates of response to CT or symptom status among premenopausal, perimenopausal, and postmenopausal women.

CONCLUSIONS

We found no support for the hypotheses that response to CT or the rates of change in depressive symptoms are moderated by reproductive status. The findings, however, are limited by the absence of early follicular phase serum sampling/analysis to estimate hormone levels and the reliance on self-report to establish menopausal status. These data motivate a full investigation of the effects of reproductive status on response to psychosocial interventions.

Effects of sex and rearing environment on imipramine response in mice

RATIONALE

Antidepressant treatments are commonly prescribed, but few studies have been published, even in animal models, on differences in reactivity to antidepressants with respect to rearing environment and sex.

OBJECTIVES

Using a mouse model, we investigated the hypothesis that rearing environment (weaning time) and sex could impact responses to imipramine treatment.

METHODS

ICR mice were assigned to four groups for each sex: early weaned saline or imipramine treated, normally weaned saline or imipramine treated. Early weaning was conducted on postnatal day 14. All groups were injected intraperitoneally with drug or vehicle for 2 weeks from the age of 6 weeks and tested in the elevated plus maze to estimate anxiety levels. Hippocampal neurogenesis was also assessed with immunostaining for calretinin and calbindin because it has suggested that neurogenesis is required for the behavioral effects of antidepressants.

RESULTS

Imipramine treatment decreased anxiety levels in females, but not in males, in the normal weaning condition. By contrast, the same treatment decreased anxiety levels in males, but not females, in the early weaning condition. Hippocampal changes, which correlated these behavioral responses to imipramine, were seen in the extragranule cell layer: the number of calretinin-positive cells was increased by imipramine in females, but not in males, in the normal weaning condition. In the early weaning condition, however, the treatment was associated with similar changes in males but not in females.

CONCLUSIONS

The results suggest that rearing environment and sex differences are implicated in responses to imipramine treatment with respect to anxiety behavior and neurogenesis in the hippocampus.

Comprehensive review of factors implicated in the heterogeneity of response in depression

BACKGROUND

Heterogeneity in overall response and outcomes to pharmacological treatment has been reported in several depression studies but with few sources that integrate these results. The goal of this study was to review the literature and attempt to identify nongenetic factors potentially predictive of overall response to depression treatments.

METHODS

A comprehensive review of the literature from the last 10 years was performed using three key databases (PubMed, EMBASE, and Cochrane). All relevant studies that met the inclusion criteria were selected and scored for their levels of evidence using the NICE scoring method. A subjective assessment of the strength of evidence for each factor was performed using predefined criteria.

RESULTS

Our broad search yielded 76 articles relevant to treatment heterogeneity. Sociodemographic factors, disease characteristics, and comorbidities were the most heavily researched areas. Some of the factors associated with more favorable overall response include being married, other social support, and low levels of baseline depressive symptoms. Evidence relating to baseline disease severity as a factor predictive of antidepressant response was particularly convincing among the factors reviewed. The presence of comorbid anxiety and pain contributed to worse antidepressant treatment outcomes.

CONCLUSIONS

Several factors either predictive of or associated with overall response to antidepressant treatment have been identified. Inclusion of factors predictive of response in the design of future trials may help tailor treatments to depression patients presenting to the average clinical practice, resulting in improved outcomes.

Low dietary or supplemental zinc is associated with depression symptoms among women, but not men, in a population-based epidemiological survey

BACKGROUND

Prior studies indicate that the biochemical alterations of depressive episodes result in decreased serum zinc concentrations. Given these findings, it is plausible that consistently low dietary zinc intakes contribute to depressive symptoms, yet epidemiological data are lacking. The authors tested the hypothesis that low zinc intake is associated with depressive symptoms using cross-sectional data from the population-based Boston Area Community Health survey (2002-2005).

METHODS

Dietary and supplement use data were collected by validated food frequency questionnaire. Current depressive symptoms were assessed by the abridged validated Center for Epidemiologic Studies Depression scale and analyzed using multivariate logistic regression, adjusting for sociodemographic, health and lifestyle characteristics.

RESULTS

Results showed an interaction (P=0.03) with gender, whereby zinc was associated with depressive symptoms in women (N=2163), but not men (N=1545). Women with low dietary or supplemental zinc intake were more likely to have depressive symptoms (e.g., dietary zinc quartile 1 vs. 4, OR=1.76, 95% CI: 1.26, 2.45; P-trend=0.004; supplemental zinc P-trend=0.03). Associations were stronger among women using antidepressant medications (e.g., total zinc OR=4.75, 95% CI: 1.98, 11.4; P-trend=0.0005).

LIMITATIONS

The cross-sectional, observational nature of the study leaves uncertain whether the observed associations represent actual causal relationships between zinc intake and depressive symptoms.

CONCLUSIONS

These findings suggest: (1) gender-specific pathophysiological mechanisms of depression, (2) inadequate dietary zinc intake contributes to depressive symptoms in women, and (3) supplemental zinc is a beneficial adjunct to antidepressant therapy in women. Additional research on both men and women is needed to verify these novel findings. If confirmed by other studies, the potential importance of adequate zinc intake is underscored by the recognized limitations of pharmacotherapy for depression.

Trauma reactivation under the influence of propranolol: an examination of clinical predictors

BACKGROUND

In two recent studies conducted by our group, a treatment combining propranolol with a brief reactivation session subsequently reduced posttraumatic stress disorder (PTSD) symptom severity and diagnosis, as well as reducing psychophysiological responses during trauma-related script-driven imagery. One likely explanation for those results is that memory reconsolidation was blocked by propranolol.

OBJECTIVE

We explored the influence of various predictors on treatment outcome (i.e., PTSD severity), and whether the treated individuals improved in other important domains of functioning associated with PTSD.

METHOD

Thirty-three patients with longstanding PTSD participated in a 6-week open-label trial consisting of actively recalling one's trauma under the influence of propranolol, once a week.

RESULTS

Treated patients reported a better quality of life, less comorbid depressive symptoms, less negative emotions in their daily life and during trauma recollections. Women were also found to improve more than men. Type of trauma (childhood vs. adulthood), time elapsed since trauma, borderline personality traits, depressive symptoms severity, Axis I comorbidity, and age did not influence treatment outcome.

CONCLUSION

These results must await publication of a randomized-controlled trial to further delineate effectiveness with this novel treatment approach.

Gender differences in 12-week antidepressant treatment outcomes for a naturalistic secondary care cohort: the CRESCEND study

This study aimed to determine whether men and women with depression differ in socio-demographic, treatment-related characteristics, and in their responses to treatment with antidepressants, as well as to explore differences in treatment outcomes by menopausal status. From a nationwide sample of 18 hospitals in South Korea, 723 depressive patients were recruited. After baseline evaluation, they received naturalistic clinician-determined antidepressant interventions. Assessment scales for evaluating depression (HAMD), anxiety (HAMA), global severity (CGI-s), and functioning (SOFAS) were administered at baseline and re-evaluated at 1, 2, 4, 8, and 12 weeks later. At baseline, women were older, less educated, less likely to be employed, had lower income, were more likely to be married, and had longer illness duration than men. There were no gender differences in the treatment-regime received. After adjustment for baseline status, women were more likely to achieve HAMD remission (OR=1.51), HAMD response (OR=1.64), and HAMA response (OR=1.61). Women also experienced shorter times to HAMD response, HAMA response, and CGI-s remission. Postmenopausal women showed higher HAMA response with newer dual action antidepressants than premenopausal women. Women were found to have better outcomes following antidepressant treatment than men, and postmenopausal women had a better response on anxiety symptoms with newer dual action antidepressants.

Gender differences in antidepressant drug response

Epidemiological studies suggest there are considerable differences in the prevalence and presentation of depression in men and women. Women are more than twice as likely to be diagnosed with depression and may also report more atypical and anxiety symptoms than men. Men and women also differ in the metabolism and distribution of antidepressants and the presence of oestrogen in women of childbearing age may interfere with the mechanism of action of a number of antidepressants. These differences have led many researchers to question whether antidepressants are equally effective and tolerated in men and women. While some reports suggest that selective serotonin re-uptake inhibitors (SSRIs) are more effective and result in fewer adverse drug reactions in women than tricyclic antidepressants (TCAs), gender differences in antidepressant response remains a controversial topic. The potential effects of antidepressant exposure in utero and in breast milk further complicate treatment options for antenatal and postnatal depression. While some research suggests the SSRI paroxetine is teratogenic, further carefully designed naturalistic studies are required to fully evaluate these effects. Finally, response to antidepressants and the occurrence of adverse drug reactions is marked by inter-individual variability which may be in part due to genetic differences. Future studies should therefore consider genotypes of the mother, foetus and infant in antidepressant response.