Gender differences in the efficacy of fluoxetine and maprotiline in depressed patients: a double-blind trial of antidepressants with serotonergic or norepinephrinergic reuptake inhibition profile

Antidepressant effects of the muscarinic cholinergic receptor antagonist scopolamine: a review

The muscarinic cholinergic receptor system has been implicated in the pathophysiology of depression, with physiological evidence indicating this system is overactive or hyperresponsive in depression and with genetic evidence showing that variation in genes coding for receptors within this system are associated with higher risk for depression. In studies aimed at assessing whether a reduction in muscarinic cholinergic receptor function would improve depressive symptoms, the muscarinic receptor antagonist scopolamine manifested antidepressant effects that were robust and rapid relative to conventional pharmacotherapies. Here, we review the data from a series of randomized, double-blind, placebo-controlled studies involving subjects with unipolar or bipolar depression treated with parenteral doses of scopolamine. The onset and duration of the antidepressant response are considered in light of scopolamine's pharmacokinetic properties and an emerging literature that characterizes scopolamine's effects on neurobiological systems beyond the cholinergic system that appear relevant to the neurobiology of mood disorders. Scopolamine infused at 4.0 μg/kg intravenously produced robust antidepressant effects versus placebo, which were evident within 3 days after the initial infusion. Placebo-adjusted remission rates were 56% and 45% for the initial and subsequent replication studies, respectively. While effective in male and female subjects, the change in depression ratings was greater in female subjects. Clinical improvement persisted more than 2 weeks following the final infusion. The timing and persistence of the antidepressant response to scopolamine suggest a mechanism beyond that of direct muscarinic cholinergic antagonism. These temporal relationships suggest that scopolamine-induced changes in gene expression and synaptic plasticity may confer the therapeutic mechanism.

Do menopausal status and use of hormone therapy affect antidepressant treatment response? Findings from the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study

BACKGROUND

Menopausal status and use of hormonal contraception or menopausal hormone therapy (HT) may affect treatment response to selective serotonin reuptake inhibitors (SSRIs). This report evaluates whether menopausal status and use of hormonal contraceptives or menopausal HT affect outcome in women treated with citalopram.

METHODS

In the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study, 896 premenopausal and 544 postmenopausal women were treated with citalopram for 12-14 weeks. Baseline demographic and clinical characteristics were used in adjusted analysis of the effect of menopausal status and use of hormonal contraceptives or menopausal HT on outcomes. Remission was defined as final Hamilton Rating Scale for Depression-17 (HRSD(17)) ≤7 or Quick Inventory of Depressive Symptomatology-Self-Report (QIDS-SR(16)) score ≤5 and response as ≥50% decrease from the baseline QIDS-SR(16) score.

RESULTS

Premenopausal and postmenopausal women differed in multiple clinical and demographic baseline variables but did not differ in response or remission rates. Premenopausal women taking hormonal contraceptives had significantly greater unadjusted remission rates on the HRSD(17) and the QIDS-SR(16) than women not taking contraception. Response and remission rates were not different between postmenopausal women taking vs. not taking HT. Adjusted results showed no significant difference in any outcome measure across menopause status in women who were not taking contraception/HT. There were no significant differences in adjusted results across HT status in premenopausal or postmenopausal women.

CONCLUSIONS

In this study, citalopram treatment outcome was not affected by menopausal status. Hormonal contraceptives and HT also did not affect probability of good outcome.

Gender-specific effects of fluoxetine on hippocampal glucocorticoid receptor phosphorylation and behavior in chronically stressed rats

Chronic psychosocial isolation stress (CPSI) modulates glucocorticoid receptor (GR) functioning in Wistar male rat hippocampus (HIPPO) through alteration of nuclear GR phosphorylation and its upstream kinases signaling, which parallels animal depressive-like behavior. The current study investigated potential gender specificities regarding the effect of chronic therapy by an antidepressant fluoxetine (FLU) on GR signaling in HIPPO and depressive-like behavior in CPSI animals. FLU was administrated to female and male naïve or CPSI rats for 21 days and GR protein, its phosphorylation status and upstream kinases, as well as GR and BDNF mRNA were followed in HIPPO together with animal serum corticosterone (CORT) and depressive-like behavior. The results showed that CPSI increased immobility in males versus hyperactivity in females and disrupted nuclear pGR232-Cdk5 pathway and JNK signaling in a gender-specific way. In contrast, in both genders CPSI increased the nuclear levels of GR and pGR246 but decreased CORT and mRNA levels of GR and BDNF. Concomitant FLU normalized the depressive-like behavior and altered the nuclear pGR232-Cdk5 signaling in a gender-specific manner. In both females and males, FLU reversed the nuclear levels of GR and pGR246 without affecting CORT and GR mRNA levels. In contrast, FLU exhibited gender-specific effect on BDNF mRNA in CPSI animals, by increasing it in females, but not in males. In spite of normalization the total nuclear GR level upon FLU treatment in both gender, down-regulation of GR mRNA is possibly maintained through prevalence of pGR232 isoform only in males. The gender-specific alterations of pGR232-Cdk5 signaling and BDNF gene expression in HIPPO and normalization of depressive-like behavior upon FLU treatment distinguishes this signaling pathway as potential future antidepressant target for gender-specific therapy of stress related mood disorders.

The Neurobiology of Depression and Anxiety: How Do We Change from Models of Drug Efficacy to Understanding Mood and Anxiety Disorders?

Current treatments for depression and anxiety disorders are only effective in approximately half of the patient population. Effective treatments have negative side-effects including sexual dysfunction, weight gain and gastrointestinal problems. Furthermore, even when patients achieve remission, they often need to increase dosage or change treatment across their lifetime as efficacy weakens. The majority of treatments being used today are based on the monoamine hypothesis of depression, a theory of depression that was based on the effectiveness of drugs discovered by chance to alleviate the symptoms of depression. This chapter provides an overview of the neurobiology of depression and anxiety disorders within the context of drug discovery. The chapter starts with what we currently know about these disorders through the lens of the monoamine hypothesis of depression. We then provide a background into the animal models of depression and anxiety that are being used to understand the underlying biology of these disorders and test new treatments. Work conducted using these animal models has directed human imagining and has provided us with new information about both the molecular and cellular mechanism of depression and anxiety as well as the neural circuitry controlling these disorders. Finally, we will conclude with a discussion of new treatments being developed based on empirical evidence about the neurobiology of depression and anxiety and the need to develop more personalized treatments in the future. It is hoped that these new drugs will be able to provide effective treatment for more people, with fewer negative side-effects.

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.

Treatment of depression associated with the menstrual cycle: premenstrual dysphoria, postpartum depression, and the perimenopause

Several forms of depression are unique to women because of their apparent association with changes in gonadal hormones, which in turn modulate neuroregulatory systems associated with mood and behavior. This review examines the evaluation and treatment of depression that occurs premenstrually, postpartum, or in the perimenopause on the basis of current literature. The serotonergic antidepressants consistently show efficacy for severe premenstrual syndromes (PMSs) and premenstrual dysphoric disorder (PMDD), and are the first-line treatment for these disorders. The use of antidepressants for postpartum depression is compromised by concerns for effects in the infants of breast-feeding mothers, but increasing evidence suggests the relative safety of the antidepressant medications, and the risk calculation should be made on an individual basis. Estradiol may be effective for postpartum depression and for moderate-to-severe major depression in the perimenopause. In spite of its frequent use, progesterone is not effective for the mood and behavioral symptoms of PMS/PMDD, postpartum depression, or perimenopausal depressive symptoms.

Sex-dependent modulation of treatment response

The response to a psychotropic medication reflects characteristics of both the medication and the substrate, ie, the individual receiving the medication. Sex is an individual characteristic that influences all elements of the pharmacokinetic process - absorption, distribution, metabolism, and elimination. The effects of sex on these components of the pharmacokinetic process often counterbalance one another to yield minimal or varying sexual differences in blood levels achieved. However, sex also appears to influence pharmacodynamics, the tissue response to a given level of medication. Consideration by the practitioner of sex as a possible contributing factor to treatment nonresponse will enhance the efficacy and precision of clinical interventions.

Raphe-Hippocampal Serotonin Neurotransmission In The Sex Related Differences of Adaptation to Stress: Focus on Serotonin-1A Receptor

Stress is the major predisposing and precipitating factor in the onset of depression which is the most significant mental health risk for women. Behavioral studies in animal models show that female sex though less affected by an acute stressor; exposure to repeated stressors induces coping deficits to impair adaptation in them. A decrease in the function of 5-hydroxytryptamine (5-HT; serotonin) in the hippocampus and an increased function of the 5-HT-1A receptor in the raphe nucleus coexist in depression. Pharmacological and neurochemical data are relevant that facilitation of serotonin neurotransmission via hippocampus due to desensitization of somatodendritic 5-HT1A receptors may lead to adaptation to stress. The present article reviews research on sex related differences of raphe-hippocampal serotonin neurotransmission to find a possible answer that may account for the sex differences of adaptation to stress reported in preclinical research and greater incidence of depression in women than men.

The effects of serotonin transporter promoter and monoamine oxidase A gene polymorphisms on trait emotional intelligence

OBJECTIVE

The purpose of this study was to evaluate the influences of major serotonin-related genetic variants of the serotonin transporter-linked promoter region (5-HTTLPR), tryptophan hydroxylase 1 gene (TPH1) and monoamine oxidase A gene (MAOA-EcoRV) on trait emotional intelligence (EI).

METHODS

The Trait Meta-Mood Scale (TMMS) measuring trait EI and genotyping were performed in 336 healthy Korean college students (204 males, 132 females).

RESULTS

Among the male participants, those with the T genotype of MAOA (lower MAOA activity) had significantly lower subscale scores on the TMMS than those with the C genotype (higher MAOA activity) did. Additionally, male participants with the s/s genotype of the 5-HTTLPR gene had significantly lower attention subscale scores and total TMMS scores than those with the non-s/s (l/l + l/s) genotypes did. Among the female participants, there were no associations between any of the 5-HTTLPR, TPH1 or MAOA-EcoRV polymorphisms and any of the TMMS scores.

CONCLUSION

These findings suggest a potential genetic basis of EI with regard to attention to one's own feelings involving the serotonin system in males.

Behaviour of a genetic mouse model of depression in the learned helplessness paradigm

RATIONALE

H/Rouen (displaying a helpless phenotype in the tail suspension test) mice exhibiting features of depressive disorders and NH/Rouen (displaying non-helpless phenotype) mice were previously created through behavioural screening and selective breeding. Learned helplessness (LH), in which footshock stress induces a coping deficit, models some aspects of depression in rodents, but so far, fewer LH studies have been performed in mice than in rats.

OBJECTIVES

To study H/Rouen and NH/Rouen in the LH paradigm.

RESULTS

When CD1 mice were submitted to footshock with various training durations and shock intensities, the most suitable parameters to induce a behavioural deficit were 0.3 mA and four training sessions. A significantly longer latency to escape shocks was found in male H/Rouen mice compared to male NH/Rouen mice. On the other hand, once shocked, NH/Rouen mice showed more severe coping deficits than H/Rouen mice. In addition, a sub-chronic treatment with fluoxetine lacked efficacy in NH/Rouen mice, whereas it improved performances in H/Rouen mice. We also found that a shock reminder at day 8, subsequent to inescapable shocks, maintained helplessness for 20 days. Finally, female H/Rouen mice responded to chronic fluoxetine administration after 10 days of treatment, while a 20-day treatment was necessary to improve the behavioural deficit in H/Rouen male mice.

CONCLUSION

H/Rouen and NH/Rouen lines displayed different despair-related behaviour in the LH paradigm. Fluoxetine had beneficial effects after sub-chronic or chronic but not acute treatment of H/Rouen mice, thus providing a pharmacological validation of the protocols.

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.

The impact of gender on antidepressants

There is a large body of literature debating whether and how gender affects the metabolism, side-effect profile, and efficacy of antidepressants. Gender differences in antidepressant pharmacokinetics and efficacy profiles have been attributed to not only anatomic and physiological differences between the sexes, but also behavioral factors, comorbid disorders, and gender-specific conditions, such as pregnancy and menopause. Despite the large body of research on this topic, few definitive conclusions regarding effects of gender on antidepressant treatment exist, and much of this research is incomplete, contradictory, or not fully used to optimize the administration of antidepressants and the response to treatment. This chapter will review the latest research on gender-specific effects of antidepressant treatment, focusing on the overall, gender-related differences in efficacy, metabolism, and side-effect profile of antidepressants, and how these differences can be used to better optimize treatment of depression in a clinical setting.

Scopolamine produces larger antidepressant and antianxiety effects in women than in men

Some antidepressant agents generate differential benefit based on gender. Blocking cholinergic muscarinic receptors using scopolamine produces robust and rapid antidepressant effects in males and females combined. This study evaluated if males and females differ in the antidepressant response magnitude following scopolamine administration. A total of 52 male and female outpatients meeting criteria for recurrent major depressive or bipolar disorder participated in a double-blind, randomized, placebo-controlled, crossover clinical trial involving seven i.v. infusions of placebo or scopolamine (4 μg/kg). Following a single-blind placebo lead-in, participants entered either a placebo-block/scopolamine-block or a scopolamine-block/placebo-block sequence. Each block included three sessions. Clinical ratings were acquired before each infusion and included the Montgomery-Asberg Depression Rating Scale (MADRS) and the Hamilton Anxiety Rating Scale (HAM-A). A treatment group × block interaction (F=21.0, p<0.001) was observed in MADRS scores across gender, and the reduction was significant by the evaluation following the first scopolamine administration (F=8.4, p=0.006). The treatment group × block interaction was also significant in males (F=3.8, p=0.043) and females (F=35.6, p<0.001) separately. A block × gender interaction (F=7.4, p=0.009) indicated that the response magnitude was larger in women. The treatment × block interaction was significant for the HAM-A across gender (F=12.0, p<0.001), and was significant for females (F=24.9, p<0.001) but not for males (F=1.3, p=0.30). When comparing the baseline block to study end, the block × gender interaction (F=12.6, p=0.001) showed that the antianxiety response was greater in women. Men and women show a rapid antidepressant response following scopolamine, but the magnitude of response is larger in women than in men.

The influence of menopause status and postmenopausal use of hormone therapy on presentation of major depression in women

OBJECTIVE

The purpose of this study was to determine whether there are differences in depression characteristics among premenopausal, perimenopausal, and postmenopausal women with major depressive disorder. This study also evaluated these differences between postmenopausal women with major depressive disorder who are taking and not taking hormone therapy.

METHODS

Analyses conducted with data from the Sequenced Treatment Alternatives to Relieve Depression study focused on female outpatients with nonpsychotic major depressive disorder seeking treatment in 41 primary or psychiatric care settings across the United States. Baseline demographic and clinical characteristics were compared among women not taking hormone therapy who were premenopausal (n = 950), perimenopausal (n = 380), or postmenopausal (n = 562). These comparisons were also made between postmenopausal women (n = 768) taking (n = 171) or not taking (n = 562) hormone therapy.

RESULTS

After adjusting for sociodemographic and clinical baseline differences, premenopausal women were more likely to present with irritability than were either perimenopausal or postmenopausal women and were more likely to have decreased appetite and less likely to have early-morning insomnia than were perimenopausal women. Postmenopausal women were more likely to have suicidal ideation and poorer physical functioning than were either of the other groups and were more likely to have sympathetic arousal and gastrointestinal symptoms than were premenopausal women. After adjusting for baseline differences, postmenopausal women taking hormone therapy had better physical functioning, fewer melancholic features, less sympathetic arousal, and more lack of involvement in activities than did women not taking hormone therapy.

CONCLUSIONS

Menopause status and postmenopausal use of hormone therapy may influence the clinical presentation of major depressive episodes in women.

Sex differences in the pharmacokinetics and pharmacodynamics of antidepressants: an updated review

BACKGROUND

An increasing number of studies have reported differences in the pharmacokinetics and/or pharmacodynamics of antidepressants between women and men.

OBJECTIVES

This article updates previously published literature describing sex differences in the pharmacokinetics and pharmacodynamics of antidepressants, and examines specific issues that face women with psychiatric illness.

METHODS

An English-language literature search was performed with the PubMed database (March 2003-December 2008) using combinations of the search terms sex, gender, and antidepressants. In addition, each antidepressant was identified in the 63rd edition of the Physicians' Desk Reference.

RESULTS

The current data suggest that the pharmacokinetics of antidepressants can be substantially different between women and men. Likewise, the response to antidepressants can be quite variable, including sex differences in adverse effects and time to response.

CONCLUSIONS

Despite the many sex differences reported, there is still little published work systematically evaluating potential sex differences in antidepressant pharmacokinetics and pharmacodynamics. More research is needed to guide the treatment of depression and other mental illnesses.

Influence of gender and menopausal status on antidepressant treatment response in depressed inpatients

The present study investigated the influence of gender and menopausal status on treatment response in depressed inpatients, treated with either imipramine or fluvoxamine. The patients were divided into three groups: men, premenopausal women and postmenopausal women. A multivariate analysis was performed using the difference in Hamilton score (pretreatment - post-treatment) for imipramine and fluvoxamine as dependent variable. The following independent variables were used: the baseline Hamilton score, the antidepressant used, the gender-group and the interaction between the type of antidepressant and gender. In total, 138 patients with a DSM IV diagnosis of depressive disorder were analysed. Men responded more favorably to imipramine (B = 7.12, P = 0.005). Premenopausal women had a better response rate to fluvoxamine than men (B = -8.66, P = 0.027). In depressed inpatients, men respond more favorably to imipramine than to fluvoxamine. Premenopausal women respond more frequently to fluvoxamine than men.

Are there differences between serotonergic, noradrenergic and dual acting antidepressants in the treatment of depressed women?

BACKGROUND

This study aims to investigate if there is a differential outcome of serotonergic and noradrenergic antidepressant treatment and if menopausal status has an impact on antidepressant response in depressed women.

METHODS

Data of the 111 depressed women who were included and completed the previous four open-label studies where patients were evaluated six times during a 10-week period, were pooled in the current study. Each of the reboxetine, sertraline and venlafaxine groups consisted of 37 depressed women. Patients were also divided into two subgroups of age, determining the 44 years as the cut-off point representing the menopausal status.

RESULTS

No significant difference was observed in the percent change of Hamilton Depression Rating Scale-17 (HDRS) and remission rates among treatment groups. Percent changes in Clinical Global Impression-Severity of Illness scale (CGI-S) and response rates were in favour of venlafaxine group at week 10. Individual HDRS items 2, 3, 4, 5 and 6 demonstrated significant improvement in the sertraline group, whereas HDRS item 7 demonstrated significant improvement in the venlafaxine group. An early reduction in anxiety subscale was observed in the venlafaxine group. Menopausal status had no impact on the outcome measures.

CONCLUSIONS

These results suggest that noradrenergic and serotonergic activity do not differ from each other in treating depressed women. However, serotonergic activity appears to be more prominent in some particular symptoms such as feelings of guilt, suicidal ideation and sleep. Also, menopause does not appear to affect antidepressants' benefit in depressed women.

Prozac during puberty: distinctive effects on neurogenesis as a function of age and sex

Neurogenesis is a possible substrate through which antidepressants alleviate symptoms of depression. In adult male rodents and primates, chronic treatment with fluoxetine increases neurogenesis in the hippocampal formation. Little is known about the effects of the antidepressant on neurogenesis during puberty or in female animals at any age. Therefore we examined the effects of chronic fluoxetine treatment on cell proliferation and survival in male and female rats during puberty and adulthood. Adult and peri-pubescent male and female rats were treated chronically with fluoxetine (Prozac, 5 mg/kg) or saline. Subsequently rats received a single injection of 5-bromo-2'-deoxyuridine (BrdU; 200 mg/kg) to label DNA synthesis. Rats were sacrificed 2 h, 24 h, or 28 days after BrdU injection to examine cell proliferation, survival and cell fate. Fluoxetine increased cell proliferation in adult male rats but not in peri-pubescent males or female rats of any age or stage of the estrous cycle. Treatment did not alter the number of surviving cells in the male hippocampus but decreased survival in the female hippocampus. Thus, fluoxetine has distinctive effects on neurogenesis as a function of age and sex. Circulating levels of the stress hormone corticosterone were also examined. Treatment of female rats with fluoxetine during puberty decreased circulating levels of corticosterone in adults, even in the absence of the drug suggesting disruption of maturation of the hypothalamic-pituitary-adrenal axis.

Partial clinical response to 2 weeks of 2 Hz repetitive transcranial magnetic stimulation to the right parietal cortex in depression

The aim of this treatment study was to evaluate the therapeutic effects of repetitive transcranial magnetic stimulation (rTMS) over the right parietal cortex in depression. In a double-blind, sham-controlled design ten consecutive sessions of 2 Hz rTMS (inter-pulse interval 0.5 s) at 90% motor threshold to the right parietal cortex (2400 pulses per session) were applied to 34 patients with the primary diagnosis of DSM-IV depression and a score of > or =15 on the 17-item Hamilton Rating Scale for Depression (HAMD). The primary outcome measures were the percentage change from baseline on the 17-item HAMD scores after ten sessions, and the percentage of clinical (defined as > or =50% reduction in HAMD score) and partial clinical (defined as > or =30% reduction in HAMD score) responders. Reduction of HAMD scores in the real rTMS treatment (mean real+/-S.D., -19.9+/-32.5%) was not statistically different from the sham rTMS treatment (mean sham+/-S.D., -5.6+/-28.4%), and the number of clinical responders did not differ between treatments. However, a significant greater number of partial clinical responders were observed in the real (43.8%) compared to the sham rTMS treatment (6.3%). This study provides the first evidence showing that 2 Hz rTMS over the right parietal cortex may have antidepressant properties, and warrants further research.

Effects of orally administered lavender essential oil on responses to anxiety-provoking film clips

BACKGROUND

Lavender odour is commonly used to alleviate mild anxiety. Double blind studies are difficult to conduct with odours, and there are few reliable investigations of lavender's efficacy.

METHOD

Orally administered lavender capsules (placebo, 100, 200 microl) were tested in a randomised between-subjects (n = 97) double-blind study. Film clips were used to elicit anxiety. Measures included anxiety, State Trait Anxiety Inventory (STAI), mood, positive and negative affect scale (PANAS), heart rate (HR), galvanic skin response (GSR), and heart rate variation (HRV). Following baseline measurements capsules were administered. Participants viewed a neutral film clip, then an anxiety-provoking and light-hearted recovery film clip.

RESULTS

For the 200 microl lavender dose during the neutral film clip there was a trend towards reduced state anxiety, GSR and HR and increased HRV. In the anxiety-eliciting film, lavender was mildly beneficial in females but only on HRV measures. In males sympathetic arousal increased during the anxiety film (GSR). HRV significantly increased at 200 microl during all three film clips in females, suggesting decreased anxiety.

CONCLUSION

These findings suggest that lavender has anxiolytic effects in humans under conditions of low anxiety, but these effects may not extend to conditions of high anxiety.

Serotonin transporter polymorphism (5-HTTLPR) association with melancholic depression: a female specific effect?

Earlier studies yielded inconsistent results on the association between variation in the serotonin transporter (5-HTT) gene and depression, with evidence for a differential effect of the 5-HTTLPR on melancholic versus atypical depression. To further delineate the impact of 5-HTT gene variation on psychopathology in depression, in this analysis the influence of the 5-HTTLPR and the functionally closely related 5-HTT rs25531 was investigated in 340 Caucasian patients with a major depressive episode (DSM-IV) with particular attention to the subtype of depression (melancholic depression versus atypical depression) applying logistic regression models adjusted for age and gender. The homozygous, more active 5-HTTLPR LL genotype was significantly associated with melancholic depression (odds ratio, OR, 1.7; 95% confidence interval, CI, 1.1-2.6; P=0.04), with the effect originating in the female subgroup of patients (OR 1.9; 95%CI 1.0-3.4; P=0.05). Also, the more active 5-HTTLPR/5-HTT rs25531 haplotype L(A)L(A) conveyed a significant risk for melancholic depression (OR 2.0; 95%CI 1.3-3.1; P=0.001), again only in the female subsample of patients (OR 2.1; 95%CI 1.1-4.1; P=0.02). The present results provide further support for an association of genetic variation increasing serotonin transporter activity with the melancholic subtype of depression as well as evidence for a potential female-specific mechanism underlying this effect.

Sex differences in response to citalopram: a STAR*D report

OBJECTIVE

Controversy exists as to whether women with depression respond better to selective serotonin reuptake inhibitors (SSRIs) than men. The purpose of this report was to determine whether men and women differ in their responses to treatment with the SSRI citalopram using a large sample of real world patients from primary and psychiatric specialty care settings.

METHOD

As part of the sequenced treatment alternatives to relieve depression (STAR *D) study, 2876 participants were treated with citalopram for up to 12-14 weeks. Baseline demographic and clinical characteristics and outcomes were gathered and compared between men and women.

RESULTS

At baseline, women were younger, had more severe depressive symptoms and were more likely to have: early onset; previous suicide attempt(s); a family history of depression, alcohol abuse or drug abuse; atypical symptom features; and one or more of several concurrent psychiatric disorders. Despite greater baseline severity and more Axis I comorbidities, women were more likely to reach remission and response with citalopram than men.

CONCLUSIONS

Women have a better response to the SSRI citalopram than men, which may be due to sex-specific biological differences particularly in serotonergic systems.

Differential clinical effects of fluvoxamine by the effect of age in Japanese female major depressive patients

The effects of gender differences and age on the treatment response to fluvoxamine were investigated in major depressive Japanese patients. A total of 100 Japanese patients participated in this study. The daily dose of fluvoxamine was fixed to 100, 150 or 200 mg in the fourth week. This fixed dose was maintained until the end of the 6-week study. The patients were divided into 3 groups: younger females, older females, and males. Depressive symptoms were evaluated using the Montgomery and Asberg Depression Rating Scale (MADRS) at pretreatment and at 1, 2, 4, and 6 weeks after the commencement of the study. Seven of the 100 patients were excluded, and the remaining 93 patients constituted the subjects (50 females, 43 males). The number of intent-to-treat responders and non-responders was 55 and 38, respectively. There was a significant difference in the changes in the time course of the MADRS score and changes in the MADRS scores at each evaluation point between the younger and older females. Younger females demonstrated a significantly better response than older females. The results suggest that fluvoxamine is more effective in younger female patients than in older female patients.

Predictors of response to sertraline in patients with major depression

OBJECTIVE

Investigation of the characteristics of patients being treated with antidepressants would be useful in determining which patients would most likely benefit from antidepressant. The purpose of this study was to examine the possible predictors of response to sertraline in major depression.

METHOD

A retrospective cohort analysis was carried out among major depression patients. Eighty two patients were identified who were receiving sertraline to treat major depression.

RESULTS

The cumulative percentage of responders was over 80% after 6 weeks, and the cumulative percentage of responders was over 80% in patients receiving a 75 mg daily dose. Clinical factors, including age, gender, frequency of episodes, and family history were examined as possible predictors of response to sertraline. On Cox proportional hazards analysis, age, and gender were independent predictive factors of improvement with sertraline. The most influential factor was age (e(coef) = 1.894), followed by gender (e(coef) = 0.542); age over 40 years (chi(2) = 5.598, df = 1, p = 0.018) and female gender (chi(2) = 7.370, df = 1, p = 0.0066) were significantly associated with improvement.

CONCLUSIONS

A 6-week treatment period, a 75 mg daily dose, age over 40 years, and female gender appear to be predictors of response to sertraline in major depression. These factors should guide clinicians in determining the choice of antidepressant.

The unique challenges of managing depression in mid-life women

Throughout most of their lives, women are at a greater risk of becoming depressed than men. Some evidence suggests that this heightened risk is associated with increased sensitivity to the hormonal changes that occur across the female reproductive lifecycle. For some women, the peri-menopause and early post-menopausal years may constitute a "window of vulnerability" during which challenging physical and emotional discomforts could result in significant impairment in functioning and poorer quality of life. A number of biological and environmental factors are independent predictors for depression in this population, including the presence of hot flashes, sleep disturbance, history of severe premenstrual syndrome or postpartum blues, ethnicity, history of stressful live events, past history of depression, body mass index and socioeconomic status. This paper explores the current knowledge on the complex associations between mood changes and aging in women. More specifically, the biological aspects of reproductive aging and their impact on mood, psychosocial factors, lifestyle, and overall health are reviewed. In addition, evidence-based hormonal and non-hormonal therapies for the management of depression and other complaints in midlife women are discussed. Ultimately, this article should help clinicians and health professionals to address a challenging clinical scenario: a preventive and effective strategy for the management of depression in the context of the menopausal transition and beyond.

Tailoring treatment of depression for women across the reproductive lifecycle: the importance of pregnancy, vasomotor symptoms, and other estrogen-related events in psychopharmacology

Compared with men, women are at increased risk of depression, especially at several reproductive-related lifecycle points. This may be partially due to changing levels of estrogen, a hormone that can affect levels of neurotransmitters and neural proteins. As estrogen levels vary throughout the lifespan, risk of depression in women also varies, and not all treatments are appropriate or effective at all times. In adolescence, onset of depression may be associated with onset of puberty, but treating underage girls with antidepressants can risk suicidality. In females of childbearing age, mood disturbances associated with menstrual cycles signal a risk for later full-blown major depressive disorder. In depressed pregnant and postpartum women, risks of treatment versus risks of nontreatment are intricate and require case-by-case evaluation. In perimenopause, vasomotor symptoms may be harbingers of oncoming depression and also may signal the presence of dysregulated hormones and neurotransmitters. Relieving vasomotor symptoms may be a necessary dimension of treating depression. In postmenopause, response to selected antidepressants may depend on whether the patient is also taking hormone-replacement therapy. To attain optimal outcomes, modern psychopharmacologists must tailor treatment of depression to a woman's reproductive stage of life.

Suicidal behavior in young women

This article provides an update on suicidal behaviors in young women. The rates of completed suicide and suicide attempts among young women are reviewed, and the impact of race and ethnicity on these rates is described. The risk and protective factors associated with suicidal behaviors in young women are discussed, including stressful life events, mental disorders, and hormonal factors. Finally, some considerations for treating suicidal young women are included.

Evidence-based guidelines for treating depressive disorders with antidepressants: a revision of the 2000 British Association for Psychopharmacology guidelines

A revision of the 2000 British Association for Psychopharmacology evidence-based guidelines for treating depressive disorders with antidepressants was undertaken 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 May 2006. Key areas in treating depression were reviewed, and the strength of evidence and clinical implications were considered. The guidelines were drawn up after extensive feedback from participants and interested parties. A literature review is provided, which identifies the quality of evidence to inform the recommendations, the strength of which are based on the level of evidence. 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.

Antidepressant drugs and memory: insights from animal studies

This is a selective review of the literature concerning the effects of antidepressant drugs on animal memory, which was performed with the aid of the PubMed database. Monoamine oxidase inhibitors tend to either have no effect on memory or result in its improvement. Studies with cyclic antidepressants have reported no effect or, more often, memory impairments. Pre-training administration of selective serotonin reuptake inhibitors (SSRIs) has been shown to have either no effect on memory or undermine it (with some isolated exceptions, in which improvements have been recorded), while post-training administration of SSRIs has been demonstrated to improve memory or have no effect. A small group formed by the remaining antidepressants has been shown to improve memory, with the exception of trazodone, which impairs memory. These findings are discussed in the light of knowledge regarding the actions of antidepressants on several neurotransmission systems. The possibility that the effects of antidepressants on memory are the core of the therapeutic effects of these drugs is also considered.

Missed symptoms of menopause

OBJECTIVE

This review examines the available data on the efficacy of selective serotonin reuptake inhibitors (SSRIs) and serotonin-noradrenaline reuptake inhibitors (SNRIs) for treating the commonly missed climacteric symptoms of menopause.

DISCUSSION

Although some women may pass through the menopausal transition phase with few or no symptoms, the majority experience one or more symptoms serious enough to be disruptive to their lives. The most common are vasomotor symptoms (VMS; hot flushes and night sweats), but they are not the only climacteric symptoms that can negatively affect quality of life. The 'missed symptoms' of menopause -- symptoms with high prevalence and an impact on quality of life that nonetheless receive less attention than do VMS -- include mood changes, sleep disturbances and somatic complaints. These symptoms are reported by approximately half of menopausal women, with numbers varying by region and ethnic background. As with VMS, the effects of declining oestrogen levels on serotonin/noradrenaline pathways could play a role in their development.

CONCLUSIONS

Results from pilot studies of several SSRIs and SNRIs suggest that they may improve menopausal mood and sleep symptoms, but few studies have demonstrated significant improvement compared with placebo. One SNRI (venlafaxine) improved menopausal mood symptoms and two SSRIs (citalopram and paroxetine) improved sleep, each in a single placebo-controlled trial of women with VMS. Additional placebo-controlled trials are needed to determine whether SSRIs or SNRIs are effective treatment options for women who cannot or choose not to use hormone therapy.

Comorbidity moderates response to methylphenidate in the Preschoolers with Attention-Deficit/Hyperactivity Disorder Treatment Study (PATS)

OBJECTIVE

The aim of this study was to examine whether demographic or pretreatment clinical and social characteristics influenced the response to methylphenidate (MPH) in the Preschoolers with ADHD Treatment Study (PATS).

METHODS

Exploratory moderator analyses were conducted on the efficacy data from the PATS 5-week, double-blind, placebo-controlled six-site titration trial. Children (N = 165, age 3-5.5 years) were randomized to 1 week each of four MPH doses (1.25, 2.5, 5, and 7.5 mg) and placebo administered three times per day (t.i.d.). We assessed the fixed effects on the average slope in the regression outcome on moderators, weight-adjusted dose, and the moderator-by-dose interaction using SAS PROC GENMOD.

RESULTS

A significant interaction effect was found for a number of co-morbid disorders diagnosed in the preschoolers at baseline (p = 0.005). Preschoolers with three or more co-morbid disorders did not respond to MPH (Cohen's d at 7.5 mg dose relative to placebo = -0.37) compared to a significant response in the preschoolers with 0, 1, or 2 co-morbid disorders (Cohen's d = 0.89, 1.00, and 0.56, respectively). Preschoolers with more co-morbidity were found to have more family adversity. No significant interaction effect was found with the other variables.

CONCLUSIONS

In preschoolers with ADHD, the presence of no or one co-morbid disorder (primarily oppositional defiant disorder) predicted a large treatment response at the same level as has been found in school-aged children, and two co-morbid disorders predicted moderate treatment response; whereas the presence of three or more co-morbid disorders predicted no treatment response to MPH.

Neurogenesis and helplessness are mediated by controllability in males but not in females

BACKGROUND

Numerous studies have implicated neurogenesis in the hippocampus in animal models of depression, especially those related to controllability and learned helplessness. Here, we tested the hypothesis that uncontrollable but not controllable stress would reduce cell proliferation in the hippocampus of male and female rats and would relate to the expression of helplessness behavior.

METHODS

To manipulate controllability, groups of male and female rats were trained in one session (acute stress) or over seven sessions (repeated stress) to escape a footshock, whereas yoked control subjects could not escape but were exposed to the same amount of stress. Cell proliferation was assessed with immunohistochemistry of bromodeoxyuridine (BrdU) and immunofluorescence of BrdU and neuronal nuclei (NeuN). Separate groups were exposed to either controllable or uncontrollable stress, and their ability to learn to escape during training on a more difficult task was used as a behavioral measure of helplessness.

RESULTS

Acute stress reduced cell proliferation in males but did not affect proliferation in the female hippocampus. When animals were given the opportunity to learn to control the stress over seven days, males produced more cells than the yoked males without control. Repeated training with controllable stress did not influence proliferation in females. Under all conditions, males were more likely than females to express helplessness behavior, even males that were not previously stressed.

CONCLUSIONS

The modulation of neurogenesis by controllability was evident in males but not in females, as was the expression of helplessness behavior, despite the fact that men are less likely than women to experience depression.

Gender differences in the clinical effects of fluvoxamine and milnacipran in Japanese major depressive patients

Gender differences in the treatment response to fluvoxamine (selective serotonin re-uptake inhibitor) and milnacipran (serotonin/norepinephrine re-uptake inhibitor) were investigated in Japanese major depressive patients. A total of 125 Japanese patients was included in the present study. Sixty-six patients received fluvoxamine treatment. The daily dose was 50 mg/day for the first week and increased to 100 mg after 1 week, up to 200 mg after another week. Fifty-nine patients were given milnacipran. The daily dose was 50 mg/day for the first week, and up to 100 mg/day thereafter. Patients were divided into three groups: younger women (<44 years of age), older women (> or =44 years of age) and men. Depressive symptoms were evaluated using the Montgomery and Asberg Depression Rating Scale (MADRS) before treatment and at 1, 2, 4 and 6 weeks after the beginning of the study. In comparison with other groups, younger women treated with fluvoxamine demonstrated a significant difference in the time course of MADRS score change. However, these gender/age-related differences of antidepressant response were not observed in the patients treated with milnacipran. The results suggest that fluvoxamine is more effective in younger female patients than older female patients and male patients, while milnacipran is generally effective irrespective of gender or age.

Relative antidepressant efficacy of bupropion and the selective serotonin reuptake inhibitors in major depressive disorder: gender-age interactions

To determine whether age/gender-based differences in efficacy exist between bupropion and the selective serotonin reuptake inhibitors for major depressive disorder, we pooled the findings of 10 double-blind studies comparing bupropion with a selective serotonin reuptake inhibitor. Men (N=943) and women (N=1179) were divided into three age groups (younger than 40, 40-55, older than 55). Improvement in terms of the 17-item Hamilton Depression Rating Scale, as well as the Bech melancholia, anxiety-somatization, and insomnia factors of the Hamilton Depression Rating Scale was compared between the two treatment groups. Of 64 pair-wise comparisons, only one was statistically significant. Specifically, more women treated with a selective serotonin reuptake inhibitor experienced a 50% or greater decrease in Hamilton Depression Rating Scale Anxiety-Somatization scores (58.8 versus 63.8%, P=0.0394). No difference, however, was seen in the degree of resolution of Hamilton Depression Rating Scale Anxiety-Somatization scores (continuous measure) between women treated with bupropion versus a selective serotonin reuptake inhibitor (P=0.114). Bupropion and the selective serotonin reuptake inhibitors, thus, appear to be equally effective in treating depressive symptoms, as well as anxious/somatic symptoms and insomnia in depression. No gender-related or age-related differences were found except that greater improvement was seen in anxious/somatic symptoms of depression among women during selective serotonin reuptake inhibitor treatment. This finding could, however, not be replicated when improvement in anxious/somatic symptoms was defined as a continuous measure.

Sex differences in antidepressant-like effect of chronic repetitive transcranial magnetic stimulation in rats

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive neurophysiological technique. Pre-clinical and clinical studies supported that rTMS might have antidepressant effects. However, whether antidepressant effect of chronic rTMS is gender-dependent is still unknown. In this study, male and female Wistar rats received 10-day rTMS (4 trains of 15 Hz; 200 stimuli/day; 1.0 T) or control condition, and then were subjected to the forced-swim test (FST). We found that female rats consistently showed higher activity levels than males in FST and revealed the significant effects of gender and rTMS as well as the interaction of gender and rTMS. The result suggested the antidepressant-like effects of chronic rTMS on behavioral components in FST are gender-dependent. The gender discrepancy related to rTMS should not be neglected in antidepressant treatment of rTMS.

Hormonal therapy and depression: are we overlooking an important therapeutic alternative?

OBJECTIVE

This review aimed to examine evidence for the role of hormonal changes in the onset and course of depressive symptomatology and to assess the possible future role of hormonal therapies in the treatment of depression.

METHODS

A Medline and PsycINFO search of the literature published between 1965 and 2006 was made of studies of depressive symptoms and hormonal treatment in women at all stages of reproductive life.

RESULTS

The cyclic fluctuation of gonadal steroids at menarche coincides with the beginning of gender-based differences in depression rates, which continue throughout reproductive life until menopause. Modifications in hormonal status, whether related to endogenous or exogenous exposure or to hormone deprivation, appear to be associated with affective disorder in a subgroup of women. For these women, a growing body of evidence indicates a biological pattern of vulnerability to mood disorders in response to hormonal fluctuations. This could have three major implications: that women vary in vulnerability to mood disorder when abrupt change in steroid levels occur, that these effects could be cumulative across the female life span, and that women do not arrive at menopause with equal risk of mood disorders or equal susceptibility to the effects of hormonal replacement therapy as has been assumed by current clinical research and practice.

CONCLUSION

While hormonal therapies could have positive effects in the treatment and prevention of depressive disorders, further research is required to differentiate hormone-responsive subgroups of women for whom specific hormonal treatments may be most beneficial. To this end, we suggest that a multifactorial model of cumulative vulnerability, which takes into account hormonal exposure throughout life, genetic vulnerability, and environmental factors, may provide better prediction of treatment response.

Preliminary support for gender differences in response to fluoxetine for generalized anxiety disorder

Women have a higher prevalence of generalized anxiety disorder (GAD) than do men, but few studies have assessed gender differences in response to pharmacotherapy. In this study we examined gender as a correlate of response to 6 weeks of open, prospective fluoxetine treatment in 23 men and 22 women with a primary diagnosis of GAD. There was no difference by gender in age or prevalence of mood and anxiety comorbidity; however, GAD onset occurred at a significantly younger age in women compared with men. Despite a lack of difference in baseline severity measures, women had a significantly poorer response to fluoxetine as measured by both the Hamilton Anxiety Rating Scale (HAM-A) and Clinician Global Impression-Severity Scale (CGI-S). In multivariate analyses, there was a significant interaction between age of onset and gender: men with younger age of onset and women with older age of onset exhibited poorer response on the HAM-A. These data, though limited in sample size and by the post hoc nature of our analyses, offer preliminary support that women with GAD, particularly those with a later age of onset, may have a poorer response to the selective serotonin reuptake inhibitor (SSRI) fluoxetine. Larger placebo-controlled trials are needed to more definitively examine gender and treatment response in anxiety disorders.

The serotonin transporter gene: polymorphism and haplotype analysis in Russian suicide attempters

The focus on gender-specific genes associated with female suicide is justified by the possible dimorphic nature of the serotonergic system and by the greater number of suicide attempts in females. We performed analysis of the promoter (5-HTTLPR) and intron 2 (STin2 VNTR) polymorphisms and haplotypes of the serotonin transporter gene in Russian suicide attempters, separately in men and women. Our findings indicate the contribution of the SLC6A4 gene to susceptibility for suicidal behavior in women, but not in men. The L/L genotype (p = 0.013, OR = 2.09) and L10 haplotype (p = 0.04, OR = 1.77) were associated with suicide in Russian women only. Further investigations of this gene in different phenotypic groups are necessary.

Are there sex differences associated with the effects of ecstasy/3,4-methylenedioxymethamphetamine (MDMA)?

Sex has been identified as an important factor in moderating the effects of several drugs of abuse. Given the increasing popularity of ecstasy (3,4-methylenedioxymethamphetamine [MDMA]) use, it is important for researchers and clinicians to understand the factors that may influence its pharmacological actions to improve education, harm reduction and treatment efforts. This review focuses on preclinical and clinical research that examines the role of sex as an independent variable in the effects of ecstasy/MDMA. A systematic search of PsycINFO and MEDLINE electronic databases from 1966 to April 2006 was conducted. Both preclinical and clinical studies show a sexually dimorphic pattern in the acute, subacute and possibly long-term effects of ecstasy/MDMA. Specifically, adult females are more sensitive than males to the acute and subacute physical and psychological effects of ecstasy/MDMA and long-term alterations in aspects of 5-HT functioning. Conversely, males are more sensitive to the acute physiological effects of ecstasy/MDMA. These findings are consistent with research outcomes reported for other substances such as amphetamines and cocaine. Potential reasons for these sex differences and directions for future research are discussed.

Different gender response to serotonergic and noradrenergic antidepressants. A comparative study of the efficacy of citalopram and reboxetine

BACKGROUND

It is well established that depressive disorders are more prevalent in women; however gender differences in the pharmacological response to antidepressants are not a consistent finding in all reports. It is considered that this discrepancy can be explained by the fact that in most clinical trials drug use for comparative purposes is not completely different. In this study gender differences in antidepressant response with citalopram (CTP), a selective serotonin reuptake inhibitor and reboxetine (RBX), a selective noradrenaline reuptake inhibitor were evaluated in a group of young men and premenopausal women.

METHOD

Eighty-six depressed patients 18 to 40 years old participated in an 8-week double-blind clinical trial. Subjects were divided in four groups according to sex and treatment assignation: females treated with CTP (n = 25) or RBX (n = 23), and males treated with CTP (n = 19) or RBX (n = 19). Response was determined using HDRS and BDI.

RESULTS

ANOVA analysis considering change in HDRS scores from baseline to last evaluation found a significant interaction between gender and type of treatment. Females treated with CTP showed a significantly greater response than females treated with RBX, while in men no differences were observed for both drugs.

LIMITATIONS

Replication using larger sample size and longer treatment periods is required.

CONCLUSIONS

These results support previous findings which show that premenopausal women respond better than men to serotonergic antidepressants. They also support that a plausible interaction between gonadal hormones and serotonin may explain gender differences in antidepressant response.

Gender differences in response to antidepressant treatment prescribed in primary care. Does menopause make a difference?

BACKGROUND

Epidemiological surveys have consistently reported that the prevalence of major depression in women is almost twice as high as it is in men. While it seems that no major gender differences have been observed in the severity and symptomatology of depression, results regarding differences in antidepressant treatment response are controversial, especially when considering menopause in treatment response.

METHODS

A total of 242 women (95 in their menopause), and 59 men beginning antidepressant treatment with a selective serotonin reuptake inhibitor (SSRI; Citalopram, Fluoxetine, Paroxetine or Sertraline) from 16 primary care (PC) centres were followed up during 6 months. Menopause effect and gender differences in antidepressant treatment response were evaluated. Additionally, severity and symptomatology of depression were compared among genders.

RESULTS

Overall results suggest that menopause is related to a worse treatment response and to a poorer self-evaluation of global health status. No gender differences were observed in treatment response, depression severity, and symptomatology.

LIMITATIONS

Since our sample included PC participants, a wide spectrum of depression severity was considered. Additionally, menopause was assessed by means of participants' self-report.

CONCLUSIONS

Menopause seems to negatively affect SSRI treatment response of depressed women treated in PC.

Depression in children and adolescents: does gender make a difference?

The occurrence of depression is higher in females after puberty, suggesting a gender-related difference. This article reviews studies that have examined gender differences in the presentation and treatment of depression in adults and discusses how this information applies to depressed children and adolescents. The adult literature suggests that men and women vary in presentation of depression. In addition, differences exist in the pharmacokinetic properties of various medications, but it is unclear how they affect clinical treatment response. Studies of gender differences in child and adolescent depression are limited. Some studies suggest that differences seen in adults may also apply to children and adolescents. Studies of gender differences in treatment response are not available, however. Further study and evidence-based exploration are required to better understand gender differences in depression in children and adolescents.

Sex-dependent effects of fluoxetine and triiodothyronine in the forced swim test in rats

The effects of triiodothyronine (T3) and fluoxetine, administered separately and combined, on behavior of male and female rats in the forced swim test, a procedure for screening antidepressant-like activity, were determined. There were no consistent effects of low doses of fluoxetine (5 mg/kg) or T3 (20 microg/kg), administered daily for 2 weeks. Fluoxetine administered daily at 10 mg/kg for 7 days reduced immobility and increased active behaviors in male rats, but had no effects in female rats. The effects of fluoxetine in male rats were not potentiated by T3. In female rats, T3 at 100 microg/kg given daily for 7 days decreased immobility and increased swimming when these were measured 72 h after the last injection, but not when measurements were performed at an earlier time point. These results provide some support from an animal model for the efficacy of T3 as antidepressant therapy in female patients, but do not provide support for the augmentation and acceleration effects seen clinically when T3 is used in conjunction with established antidepressants such as fluoxetine.

Antidepressant response and well-being in pre-, peri- and postmenopausal women with major depressive disorder treated with fluoxetine

BACKGROUND

We assessed the impact of menopausal status on treatment response and well-being in a cohort of outpatient women with major depressive disorder (DSM-III-R criteria), who received treatment with fluoxetine (20 mg/day for 8 weeks).

METHODS

Menopausal status was defined based on age, presence of menstrual irregularity or amenorrhea and vasomotor symptoms. Remission and response of depression were defined as a 17-item Hamilton Depression Rating Scale (HAM-D-17) score <or=7 and a HAM-D-17 decrease >or=50%, respectively. Well-being was assessed by self-rating with the Symptom Questionnaire. Remitters were followed up for 28 additional weeks.

RESULTS

No differences in rates of response and remission as well as in levels of well-being were observed among pre- (n = 121), peri- (n = 28) and postmenopausal (n = 35) women at the endpoint of the acute phase, even after adjustment for baseline depression severity. Residual symptoms, however, were significantly more common in postmenopausal women, except for the continuation phase endpoint. Differences in residual symptoms during the acute phase subsided after adjustment for baseline depression severity.

CONCLUSIONS

Overall, menopausal status did not significantly affect the response to fluoxetine treatment and the degree of posttreatment well-being among major depressive disorder patients.

Sex differences in diencephalon serotonin transporter availability in major depression

BACKGROUND

Major depression is more prevalent in women than men. The present study evaluated if previous findings that demonstrated decreased 5-hydroxytryptamine (5-HT) transporter availability in depressed patients would be confirmed in a larger sample and also evaluated sex differences.

METHODS

Depressed (n = 32) and healthy subjects (n = 32), including 16 pairs of women and men, participated in an iodine-123-2 beta-carbomethoxy-3beta-(4-iodophenyltropane) ([(123)I]beta-CIT) single photon emission computed tomography (SPECT) and a magnetic resonance imaging (MRI) scan. Participants were administered [(123)I]beta-CIT (225.7 +/- 3.7 MBq) and imaged 23.0 +/- 1.6 hours later. Statistical analyses included analysis of variance and a regression analysis of the main and interactive effects of age, sex, and depression.

RESULTS

Overall, depressed patients demonstrated 12% lower diencephalon and no change in striatal or brainstem [(123)I]beta-CIT uptake. Significant age by sex, sex by depression, and age by sex by depression interactions were noted due to 22% lower diencephalon [(123)I]beta-CIT uptake in depressed women compared with less than a 1% decrease in depressed men.

CONCLUSIONS

As observed previously, diencephalon 5-HT transporter availability is decreased in depressed patients. However, the decrease appears to be sex-specific and age-dependent. These findings suggest that serotonergic mechanisms mediating depressed mood differ between men and women in an age-dependent manner and may explain why young women respond better to treatment with selective serotonin reuptake inhibitor (SSRI) antidepressants.

Gender difference in association between polymorphism of serotonin transporter gene regulatory region and anxiety

OBJECTIVE

The objective of this study was to verify the hypothesis that variation of the serotonin transporter gene promoter region (5-HTTLPR) is associated with sensitivity to stress.

METHODS

Genotyping of 5-HTTLPR and evaluation of emotional states were performed on 194 participants. Participants' emotional states were evaluated using the Perceived-Stress Scale (PSS), the State-Trait Anxiety Inventory (STAI), and the Self-rating Depression Scale (SDS).

RESULTS

There was significant GenderxGenotype interaction in STAI (state, P<.05; trait, P<.05). Females with the l/s genotype showed higher anxiety than those with the s/s genotype in both state and trait anxiety. Oppositely, males with the s/s genotype showed higher anxiety than those with the l/s genotype.

CONCLUSION

On all emotional scales, females with the l/s genotype showed high scores, contrary to males with the same genotype. Therefore, our results suggest that 5-HTTLPR l allele may be one pathway that activates negative emotion in females but acts contrary in males.

The results of the Swiss observational study of the new, fast-dissolving mirtazapine formulation in depressed patients

Objective. The purpose of the present study was to document the experience with the use of a new, fast-dissolving oral tablet (FDT, RemeronSolTab®) of mirtazapine, a NaSSA antidepressant, in the treatment of depressed patients in daily practice in Switzerland. Methods. It was an open, prospective collection of observations in a total of 1121 depressive patients (>18 years old, both sexes). The treatment duration was 8 weeks with assessments after the second and eighth week. Efficacy measures were CGI (seven points) and specific check-lists for the ratings of severity of anxiety and sleep disturbances. At the end of the trial the acceptance (eight-item questionnaire) of the new formulation was recorded too. Results. The results showed that there was highly significant (P<0.001) and rapid improvement of severity of depression, anxiety and sleep disturbances in the whole population. Subgroup analyses showed that the antidepressant efficacy was independent of gender, initial severity of depression or of the type of depression (first episode, recurrent, chronic depression). The majority of patients (80%) liked at least one of the properties of FDT and, out of 75% of patients having experience with conventional tablet, 50% stated to be better compliant with this new formulation. Conclusion. This report documents the antidepressant efficacy of mirtazapine FDT. The new formulation found good acceptance by the patients. The results also suggest a likelihood of improved compliance with the mirtazapine FDT.

Role of sex and sex steroids in mediating pituitary-adrenal responses to acute buspirone treatment in sheep

Systematic characterisation of sex differences in the serotonergic modulation of the hypothalamic-pituitary-adrenal (HPA) axis may assist with our understanding of why stress-related disorders are disproportionately represented in women. In this study, we examined the acute effects of buspirone, a serotonergic 1A receptor subtype agonist, on the endocrine endpoints of adrenocorticotrophin (ACTH) and cortisol secretion in gonadectomised male and female sheep. Each sheep was treated with an acute i.v. injection containing vehicle or buspirone (0.03, 0.1 and 0.3 mg/kg) in the presence and absence of sex steroid replacement (SSR). In males, SSR treatment consisted of testosterone (2 x 200 mg s.c. pellets) and, in females, the mid-luteal phase of the oestrus cycle was simulated by treatment with oestradiol (1 cm s.c. implant) and an intravaginal controlled internal drug release device containing 0.3 g progesterone. ACTH, cortisol, testosterone and progesterone were measured in jugular blood. Basal ACTH levels were higher in males, whereas basal cortisol levels were higher in females, regardless of sex steroid status. The magnitude of the increase in ACTH and cortisol secretion following buspirone treatment was dose-dependent. There were no differences in the ACTH responses of males and females to buspirone treatment, either in the presence or absence of sex steroid replacement. However, although the cortisol response to buspirone was greater in females, there was no discernable effect of sex steroid status in addition to this sex difference on either basal or buspirone-stimulated cortisol release. We conclude that the larger basal and buspirone-stimulated cortisol response measured in females may reflect a sex difference, either in the sensitivity of the adrenal gland to ACTH or in the catecholaminergic innervation of the adrenal gland. The lack of effect of sex and sex steroids in the ACTH secretory response to buspirone may indicate that the sex differences in serotonergic modulation of the HPA axis, as reported previously by our group, were mediated via serotonergic receptor subtypes other than the 1A receptor.