Does adding noradrenaline reuptake inhibition to selective serotonin reuptake inhibition improve efficacy in patients with depression? A systematic review of meta-analyses and large randomised pragmatic trials

Real-world characteristics of European patients receiving SNRIs as first-line treatment for major depressive disorder

BACKGROUND

Serotonin-norepinephrine reuptake inhibitors (SNRIs) are among the most frequently prescribed antidepressants (ADs) for major depressive disorder (MDD), with an increasing trend in the last decade. Given the relative dearth of information regarding rationales for their preferred use as first-line ADs in the broad clinical routine, the present study systematically investigated real-world characteristics of MDD patients prescribed either SNRIs or other AD substances across different countries and treatment settings.

METHODS

In the present secondary analyses based on a large European, multi-site, naturalistic and cross-sectional investigation with a retrospective assessment of treatment outcome, we firstly defined the proportion of MDD patients receiving SNRIs as first-line AD psychopharmacotherapy and secondly compared their sociodemographic and clinical characteristics to those patients prescribed alternative first-line ADs during their current major depressive episode (MDE).

RESULTS

Within the total sample of 1410 MDD patients, 336 (23.8 %) received first-line SNRIs. Compared to other ADs, SNRIs were significantly associated with inpatient care, suicidality and treatment resistance during the current MDE, and a longer lifetime duration of psychiatric hospitalizations. Moreover, greater severity of depressive symptoms at study entry, higher daily doses of the administered ADs, as well as more frequent prescriptions of psychopharmacotherapeutic add-on strategies in general and antipsychotic augmentation in particular, were significantly related to first-line SNRIs.

CONCLUSIONS

Considering the limitations of a cross-sectional and retrospective study design, our data point towards a preferred use of first-line SNRIs in a generally more severely ill MDD patients, although they did not lead to superior treatment outcomes compared to alternative ADs.

St. John's wort (Hypericum perforatum) and depression: what happens to the neurotransmitter systems?

St. John's wort (Hypericum perforatum) is a herbaceous plant containing many bioactive molecules including naphthodianthrones, phloroglucinol derivatives, flavonoids, bioflavonoids, proanthocyanidins, and chlorogenic acid. Evidence has shown the therapeutic effects of St. John's wort and especially its two major active components, hyperforin and hypericin, on different psychiatric and mood disorders such as posttraumatic stress disorder (PTSD), attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), and anxiety disorders. St. John's wort also induces antidepressant effects. In this review study, we aimed to discuss the role of St. John's wort in modulating depression, with respect to the role of different neurotransmitter systems in the brain. We discussed changes in the neurotransmitter levels in depression, and following use of St. John's wort. It was concluded that changes in the function and level of neurotransmitters in depression are complex. Also, St. John's wort can induce inconsistent effects on neurotransmitter levels. We also found that glutamate and acetylcholine may be the most important neurotransmitters to study in future works, because the function of both neurotransmitters in depression is unclear. In addition, St. John's wort induces a dualistic modulation on the activity of cholinergic signaling, which can be an interesting topic for future studies.

The sociodemographic and clinical profile of patients with major depressive disorder receiving SSRIs as first-line antidepressant treatment in European countries

INTRODUCTION

Due to favorable antidepressant (AD) efficacy and tolerability, selective-serotonin reuptake inhibitors (SSRIs) are consistently recommended as substances of first choice for the treatment of major depressive disorder (MDD) in international guidelines. However, little is known about the real-world clinical correlates of patients primarily prescribed SSRIs in contrast to those receiving alternative first-line ADs.

METHODS

These secondary analyses are based on a naturalistic, multinational cross-sectional study conducted by the European Group for the Study of Resistant Depression at ten research sites. We compared the socio-demographic and clinical characteristics of 1410 patients with primary MDD, who were either prescribed SSRIs or alternative substances as first-line AD treatment, using chi-squared tests, analyses of covariance, and logistic regression analyses.

RESULTS

SSRIs were prescribed in 52.1% of MDD patients who showed lower odds for unemployment, current severity of depressive symptoms, melancholic features, suicidality, as well as current inpatient treatment compared to patients receiving alternative first-line ADs. Furthermore, patients prescribed SSRIs less likely received add-on therapies including AD combination and augmentation with antipsychotics, and exhibited a trend towards higher response rates.

CONCLUSION

A more favorable socio-demographic and clinical profile associated with SSRIs in contrast to alternative first-line ADs may have guided European psychiatrists' treatment choice for SSRIs, rather than any relevant pharmacological differences in mechanisms of action of the investigated ADs. Our results must be cautiously interpreted in light of predictable biases resulting from the open treatment selection, the possible allocation of less severely ill patients to SSRIs as well as the cross-sectional study design that does not allow to ascertain any causal conclusions.

Role of Quercetin in Depressive-Like Behaviors: Findings from Animal Models

Depressive-like behavior is a highly prevalent worldwide neuropsychiatric disorder that owns a complex pathophysiologic mechanism. The available pharmacotherapy is ineffective for most patients and shown several adverse effects. Therefore, it is important to find efficacy and safe antidepressive compounds. Some phytochemicals compounds regulate the same genes and pathways targeted by drugs; therefore, diets rich in fruits and vegetables could be considered novel treatment approaches. Currently, the functional properties of quercetin acquired great interest, due to its beneficial effects on health. Quercetin is a flavonoid ubiquitously present in vegetables and fruits, interestingly for its strong antioxidant properties. The purpose of this review is to summarize the preclinical studies present in the literature, in the last ten years, aimed at illustrating the effects of quercetin pre-treatment in depressive-like behaviors. Quercetin resulted in antidepressant-like actions due to its antioxidant, anti-inflammatory, and neuroprotective effects. This pointed out the usefulness of this flavonoid as a nutraceutical compound against the development of psychological stress-induced behavioral perturbation. Therefore, quercetin or a diet containing it may become a prospective supplementation or an efficient adjuvant therapy for preventing stress-mediated depressive-like behavior.

Systematic review of pragmatic randomised control trials assessing the effectiveness of professional pharmacy services in community pharmacies

BACKGROUND

Implementation of Professional Pharmacy Services (PPSs) requires a demonstration of the service's impact (efficacy) and its effectiveness. Several systematic reviews and randomised controlled trials (RCT) have shown the efficacy of PPSs in patient's outcomes in community pharmacy. There is, however, a need to determine the level of evidence on the effectiveness of PPSs in daily practice by means of pragmatic trials. To identify and analyse pragmatic RCTs that measure the effectiveness of PPSs in clinical, economic and humanistic outcomes in the community pharmacy setting.

METHODS

A systematic search was undertaken in MEDLINE, EMBASE, the Cochrane Library and SCIELO. The search was performed on January 31, 2020. Papers were assessed against the following inclusion criteria (1) The intervention could be defined as a PPS; (2) Undertaken in a community pharmacy setting; (3) Was an original paper; (4) Reported quantitative measures of at least one health outcome indicator (ECHO model); (5) The design was considered as a pragmatic RCT, that is, it fulfilled 3 predefined attributes. External validity was analyzed with PRECIS- 2 tool.

RESULTS

The search strategy retrieved 1,587 papers. A total of 12 pragmatic RCTs assessing 5 different types of PPSs were included. Nine out of the 12 papers showed positive statistically significant differences in one or more of the primary outcomes (clinical, economic or humanistic) that could be associated with the following PPS: Smoking cessation, Dispensing/Adherence service, Independent prescribing and MTM. No paper reported on cost-effectiveness outcomes.

CONCLUSIONS

There is limited available evidence on the effectiveness of community-based PPS. Pragmatic RCTs to evaluate clinical, humanistic and economic outcomes of PPS are needed.

Interaction between Mesocortical and Mesothalamic Catecholaminergic Transmissions Associated with NMDA Receptor in the Locus Coeruleus

Noncompetitive N-methyl-D-aspartate/glutamate receptor (NMDAR) antagonists contribute to the pathophysiology of schizophrenia and mood disorders but improve monoaminergic antidepressant-resistant mood disorder and suicidal ideation. The mechanisms of the double-edged sword clinical action of NMDAR antagonists remained to be clarified. The present study determined the interaction between the NMDAR antagonist (MK801), α1 adrenoceptor antagonist (prazosin), and α2A adrenoceptor agonist (guanfacine) on mesocortical and mesothalamic catecholaminergic transmission, and thalamocortical glutamatergic transmission using multiprobe microdialysis. The inhibition of NMDAR in the locus coeruleus (LC) by local MK801 administration enhanced both the mesocortical noradrenergic and catecholaminergic coreleasing (norepinephrine and dopamine) transmissions. The mesothalamic noradrenergic transmission was also enhanced by local MK801 administration in the LC. These mesocortical and mesothalamic transmissions were activated by intra-LC disinhibition of transmission of γ-aminobutyric acid (GABA) via NMDAR inhibition. Contrastingly, activated mesothalamic noradrenergic transmission by MK801 enhanced intrathalamic GABAergic inhibition via the α1 adrenoceptor, resulting in the suppression of thalamocortical glutamatergic transmission. The thalamocortical glutamatergic terminal stimulated the presynaptically mesocortical catecholaminergic coreleasing terminal in the superficial cortical layers, but did not have contact with the mesocortical selective noradrenergic terminal (which projected terminals to deeper cortical layers). Furthermore, the α2A adrenoceptor suppressed the mesocortical and mesothalamic noradrenergic transmissions somatodendritically in the LC and presynaptically/somatodendritically in the reticular thalamic nucleus (RTN). These discrepancies between the noradrenergic and catecholaminergic transmissions in the mesocortical and mesothalamic pathways probably constitute the double-edged sword clinical action of noncompetitive NMDAR antagonists.

Recent Studies on Anti-Depressant Bioactive Substances in Selected Species from the Genera Hemerocallis and Gladiolus: A Systematic Review

Herbal therapy is a potential alternative applied to pharmacological alleviation of depression symptoms and treatment of this disorder, which is predicted by the World Health Organization (WHO) to be the most serious health problem worldwide over the next several years. It has been well documented that many herbs with psychotropic effects have far fewer side effects than a variety of pharmaceutical agents used by psychiatrists for the treatment of depression. This systematic review presents literature data on the antidepressant activity of representatives of the genera Hemerocallis (H. fulva and H. citrina Baroni, family Xanthorrhoeaceae) and Gladiolus (G. dalenii, family Iridaceae) and on biologically active compounds and their mechanisms of action to consider the application of herbal preparations supporting the treatment of depression.

Estrogen and Serotonin: Complexity of Interactions and Implications for Epileptic Seizures and Epileptogenesis

A burgeoning literature documents the confluence of ovarian steroids and central serotonergic systems in the in-junction of epileptic seizures and epileptogenesis. Estrogen administration in animals reduces neuronal death from seizures by up-regulation of the prosurvival molecule i.e. Bcl-2, anti-oxidant potential and protection of NPY interneurons. Serotonin modulates epileptiform activity in either direction i.e administration of 5-HT agonists or reuptake inhibitors leads to the acti-vation of 5-HT3 and 5-HT1A receptors tending to impede focal and generalized seizures, while depletion of brain 5-HT along with the destruction of serotonergic terminals leads to expanded neuronal excitability hence abatement of seizure threshold in experimental animal models. Serotonergic neurotransmission is influenced by the organizational activity of ster-oid hormones in the growing brain and the actuation effects of steroids which come in adulthood. It is further established that ovarian steroids bring induction of dendritic spine proliferation on serotonin neurons thus thawing a profound effect on sero-tonergic transmission. This review features 5-HT1A and 5-HT3 receptors as potential targets for ameliorating seizure-induced neurodegeneration and recurrent hypersynchronous neuronal activity. Indeed 5-HT3 receptors mediate cross-talk be-tween estrogenic and serotonergic pathways, and could be well exploited for combinatorial drug therapy against epileptogen-esis.

Approaching to the Essence of Major Depressive Disorder

Major Depressive Disorder (MDD) is a serious neuropsychic disease. It destroys person’s family relationship and social connections seriously. Latest WHO investigation disclosed nearly 4.4% of the population worldwide (approximately 322 million people) were being affected by MDD extensively [1]. While in China, Dong M, et al. reported the occurrence rate of suicide attempt during hospitalization and after the onset of MDD were 17.3% (95% CI: 12.4-23.7%) and 42.1% (95% CI: 26.1-60.0%) respectively [2]. Another research made by Grupta S, et al. announced MDD in urban China might be under-diagnosed and untreated [3].

Interaction between CYP2D6 inhibitor antidepressants and codeine: is this relevant?

INTRODUCTION

Co-occurring pain impairs depression's prognosis. Selective serotonin reuptake inhibitors (SSRIs) or serotonin and norepinephrine reuptake inhibitors (SNRIs) are first-line pharmacotherapies for depression and inhibit many cytochrome 2D6 enzymes. Codeine is a first-line treatment for pain and needs to be metabolized into morphine by cytochrome 2D6 to exert its analgesic effect. Concomitant prescription of both pharmacotherapies leads to inadequate analgesia. Areas covered: We performed a systematic review of the literature to amalgamate the current knowledge regarding the clinical effect of this association and quantified its prevalence in clinical practice in the French Pays de la Loire area using a retrospective observational cohort study design. Expert opinion: The literature review highlighted that antidepressants with moderate-to-strong inhibition of CYP2D6 should be avoided in patients receiving codeine. However, 0.44% of the 12,296 sampled patients received concomitant codeine and CYP2D6 inhibitor between January 2015 and June 2015. Switching drugs in both painful and depressive patients depends on the pain and depression subtypes. Promising drugs that both show an effect on pain and depression are currently being studied but are not usable in clinical practice. Until then, tailored communication reinforcement toward health-care professionals is needed to prevent these problematic occurrences of concomitant prescription administration.

Comparative effectiveness of dual vs. single-action antidepressants on HIV clinical outcomes in HIV-infected people with depression

OBJECTIVE

Depression is highly prevalent among people living with HIV/AIDS (PLWHA) and has deleterious effects on HIV clinical outcomes. We examined changes in depression symptoms, viral suppression, and CD4 T cells/μl among PLWHA diagnosed with depression who initiated antidepressant treatment during routine care, and compared the effectiveness of dual-action and single-action antidepressants for improving those outcomes.

DESIGN

Comparative effectiveness study of new user dual-action or single-action antidepressant treatment episodes occurring from 2004 to 2014 obtained from the Center for AIDS Research Network of Integrated Clinical Systems.

METHODS

We identified new user treatment episodes with no antidepressant use in the preceding 90 days. We completed intent-to-treat and per protocol evaluations for the main analysis. Primary outcomes, were viral suppression (HIV viral load <200 copies/ml) and CD4 T cells/μl. In a secondary analysis, we used the Patient Health Questionnaire-9 (PHQ-9) to evaluate changes in depression symptoms and remission (PHQ <5). Generalized estimating equations with inverse probability of treatment weights were fitted to estimate treatment effects.

RESULTS

In weighted intent-to-treat analyses, the probability of viral suppression increased 16% after initiating antidepressants [95% confidence interval = (1.12, 1.20)]. We observed an increase of 39 CD4T cells/μl after initiating antidepressants (30, 48). Both the frequency of remission from depression and PHQ-9 scores improved after antidepressant initiation. Comparative effectiveness estimates were null in all models.

CONCLUSION

Initiating antidepressant treatment was associated with improvements in depression, viral suppression, and CD4 T cells/μl, highlighting the health benefits of treating depression in PLWHA. Dual and single-action antidepressants had comparable effectiveness.

Effect of desvenlafaxine 50 mg and 100 mg on energy and lassitude in patients with major depressive disorder: A pooled analysis

Nine randomized, double-blind, placebo-controlled studies of major depressive disorder were pooled to evaluate the effects of desvenlafaxine 50- and 100-mg/d on energy and lassitude in adults with major depressive disorder ( n=4279). Changes from baseline to endpoint in 17-item Hamilton Rating Scale for Depression (HAM-D₁₇) Work and Activities, Retardation, and Somatic Symptoms General items, HAM-D₁₇ psychomotor retardation factor, and Montgomery-Åsberg Depression Rating Scale Lassitude item were analyzed with a mixed model for repeated measures analysis of variance. Associations between residual energy measures and functional impairment, based on the Sheehan Disability Scale, were modeled using stepwise multiple linear regression. Improvement from baseline was significantly greater for both desvenlafaxine doses versus placebo on all energy symptom outcomes at week 8 (all p⩽0.005). Both early improvement in HAM-D₁₇ psychomotor retardation at week 2 and residual energy symptoms at week 8 were associated with Sheehan Disability Scale total score at week 8 (all p⩽0.001). Among Sheehan Disability Scale remitters and responders, the HAM-D₁₇ psychomotor retardation score at week 8 was significantly lower with desvenlafaxine (both doses) than placebo. Desvenlafaxine 50 and 100 mg/d significantly improved energy and lassitude symptoms in patients with major depressive disorder. Both early improvement in energy and fewer residual energy symptoms were associated with functional improvement.

Comparative effectiveness of dual-action versus single-action antidepressants for the treatment of depression in people living with HIV/AIDS

BACKGROUND

Depression is the most common psychiatric comorbidity among people living with HIV/AIDS (PLWHA). Little is known about the comparative effectiveness between different types of antidepressants used to treat depression in this population. We compared the effectiveness of dual-action and single-action antidepressants in PLWHA for achieving remission from depression.

METHODS

We used data from the Centers for AIDS Research Network of Integrated Clinic Systems to identify 1175 new user dual-action or single-action antidepressant treatment episodes occurring from 2005 to 2014 for PLWHA diagnosed with depression. The primary outcome was remission from depression defined as a Patient Health Questionnaire-9 (PHQ-9) score <5. Mean difference in PHQ-9 depressive symptom severity was a secondary outcome. The main approach was an intent-to-treat (ITT) evaluation complemented with a per protocol (PP) sensitivity analysis. Generalized linear models were fitted to estimate treatment effects.

RESULTS

In ITT analysis, 32% of the episodes ended in remission for both dual-action and single-action antidepressants. The odds ratio (OR) of remission was 1.02 (95%CI=0.63,1.67). In PP analysis, 40% of dual-action episodes ended in remission compared to 32% in single-action episodes. Dual-action episodes had 1.33 times the odds of remission (95%CI=0.55,3.21), however the result was not statistically significant. Non-significant differences were also observed for depressive symptom severity.

LIMITATIONS

Missing data was common but was addressed with inverse probability weights.

CONCLUSIONS

Results suggest that single-action and dual-action antidepressants are equally effective in PLWHA. Remission was uncommon highlighting the need to identify health service delivery strategies that aid HIV providers in achieving full remission of their patients' depression.

The Role of Levomilnacipran in the Management of Major Depressive Disorder: A Comprehensive Review

Levomilnacipran, the more active enantiomer of the serotonin and norepinephrine reuptake inhibitor (SNRI) milnacipran, was recently approved in the US for the treatment of major depressive disorder (MDD). The drug was developed as an extended release (ER) capsule formulation to allow for once-daily administration, thereby improving patient adherence. This agent differs from other available SNRIs in having a greater potency for inhibition of norepinephrine relative to serotonin reuptake. The efficacy of levomilnacipran ER has been evaluated in seven randomised, double-blind clinical trials (one Phase II and four Phase III trials, and two long-term efficacy studies). These studies documented that levomilnacipran is generally more effective than placebo for the treatment of MDD in the short-term, whereas no firm evidence exists on long-term efficacy for relapse prevention. Preliminary evidence suggests that levomilnacipran ER may be effective in improving not only depressive symptoms but also symptoms related to functioning (social life, work, and family life). Short-and longer-term studies found that the rate of withdrawal from levomilnacipran therapy due to adverse events was rather low. Moreover the drug appeared to be generally well tolerated. The most common adverse effects included nausea, hyperhidrosis, constipation, tachycardia, palpitations, erectile dysfunction and ejaculation disorder. As hypertension or orthostatic hypotension may occur in a few patients, the cardiovascular safety of levomilnacipran needs to be more extensively investigated especially on long-term treatment. Additional active comparator trials evaluating efficacy, tolerability and cost-effectiveness are required to better define the role of levomilnacipran ER in the treatment of MDD in relation to currently available antidepressants including other SNRIs.

Chronic Pain and Mental Health Disorders: Shared Neural Mechanisms, Epidemiology, and Treatment

Chronic pain and mental health disorders are common in the general population, and epidemiological studies suggest that a bidirectional relationship exists between these 2 conditions. The observations from functional imaging studies suggest that this bidirectional relationship is due in part to shared neural mechanisms. In addition to depression, anxiety, and substance use disorders, individuals with chronic pain are at risk of other mental health problems including suicide and cigarette smoking and many have sustained sexual violence. Within the broader biopsychosocial model of pain, the fear-avoidance model explains how behavioral factors affect the temporal course of chronic pain and provides the framework for an array of efficacious behavioral interventions including cognitive-behavioral therapy, acceptance-based therapies, and multidisciplinary pain rehabilitation. Concomitant pain and mental health disorders often complicate pharmacological management, but several drug classes, including serotonin-norepinephrine reuptake inhibitors, tricyclic antidepressants, and anticonvulsants, have efficacy for both conditions and should be considered first-line treatment agents.

Whole-Brain Mapping of Neuronal Activity in the Learned Helplessness Model of Depression

Some individuals are resilient, whereas others succumb to despair in repeated stressful situations. The neurobiological mechanisms underlying such divergent behavioral responses remain unclear. Here, we employed an automated method for mapping neuronal activity in search of signatures of stress responses in the entire mouse brain. We used serial two-photon tomography to detect expression of c-FosGFP - a marker of neuronal activation - in c-fosGFP transgenic mice subjected to the learned helplessness (LH) procedure, a widely used model of stress-induced depression-like phenotype in laboratory animals. We found that mice showing "helpless" behavior had an overall brain-wide reduction in the level of neuronal activation compared with mice showing "resilient" behavior, with the exception of a few brain areas, including the locus coeruleus, that were more activated in the helpless mice. In addition, the helpless mice showed a strong trend of having higher similarity in whole-brain activity profile among individuals, suggesting that helplessness is represented by a more stereotypic brain-wide activation pattern. This latter effect was confirmed in rats subjected to the LH procedure, using 2-deoxy-2[18F]fluoro-D-glucose positron emission tomography to assess neural activity. Our findings reveal distinct brain activity markings that correlate with adaptive and maladaptive behavioral responses to stress, and provide a framework for further studies investigating the contribution of specific brain regions to maladaptive stress responses.

[Psychopharmacology of anxiety and depression: Historical aspects, current treatments and perspectives]

Pharmacological treatment of acute anxiety still relies on benzodiazepines, while chronic anxiety disorders and depression are treated with different antidepressants, according to specific indications. The monoaminergic axis is represented by two families which are being developed: (i) serotonin-norepinephrine-dopamine reuptake inhibitors (SNDRI), also called triple reuptake inhibitors (TRI), for the treatment of depression (amitifadine), (ii) multimodal antidepressants for depression and anxiety disorders (generalized anxiety disorder mainly) (tedatioxetine, vortioxetine and vilazodone). Third-generation antipsychotics (aripiprazole, lurasidone, brexpiprazole, cariprazine) appear relevant in the treatment of resistant depression and some anxiety disorders. Among the modulators of the glutamatergic axis, promising compounds include: (i) ionotropic regulators of NMDA receptors: esketamine, AVP-923 and AVP-786, CERC-301, rapastinel (Glyx-13), NRX-1074 developed for depression, rapastinel and bitopertine developed for obsessive compulsive disorder, (ii) metabotropic glutamate receptors modulators: decoglurant and basimglurant developed for depression and mavoglurant developed for obsessive compulsive disorder.

Effects of desvenlafaxine on blood pressure in patients treated for major depressive disorder: a pooled analysis

OBJECTIVE

To evaluate the effect of the serotonin-norepinephrine re-uptake inhibitor desvenlafaxine on blood pressure and incidence of new onset hypertension in pooled short-term studies and in two longer-term, randomized withdrawal studies.

RESEARCH DESIGN AND METHODS

Data from patients randomly assigned to desvenlafaxine 10 mg to 400 mg/day or placebo in 11 short-term (8-12 weeks), fixed-dose, double-blind, placebo-controlled studies of major depressive disorder (MDD) were pooled for analysis; two desvenlafaxine randomized withdrawal studies (36 and 46 weeks) were analyzed separately.

CLINICAL TRIAL REGISTRATION

www.clinicaltrials.gov , NCT00072774, NCT00073762, NCT00277823, NCT00300378, NCT00384033, NCT00798707, NCT00863798, NCT01121484, NCT00824291, NCT01432457, NCT00075257, NCT00887224.

MAIN OUTCOME MEASURES

Outcomes included change from baseline in supine systolic blood pressure (SSBP) and supine diastolic blood pressure (SDBP), assessed using a mixed model repeated measures (MMRM) analysis, and incidence of hypertension (defined as three consecutive second SDBP measures ≥90 mm Hg AND increase of ≥10 mm Hg from baseline and/or SSBP ≥140 mm Hg AND increase of ≥10 mm Hg), analyzed using Cochran Mantel Hanzael tests. Potential predictors of change in SSBP and SDBP at LOCF were examined by including predictor variables in a regression model.

RESULTS

In the pooled, short-term studies, mean changes from baseline over time in SSBP and SDBP were statistically significant compared with placebo for the desvenlafaxine doses of 10 mg/day or greater for SSBP (p ≤ 0.0004; MMRM) and 25 mg/day or greater for SDBP (p ≤ 0.0449; MMRM). The proportion of patients with new onset hypertension differed significantly from placebo for the 50, 200, and 400 mg/day doses (1.9%, 2.4%, 4.8%, respectively, vs 0.8%; all p ≤ 0.0244). Predictors of change in BP included baseline SDBP, baseline SSBP, dose, body mass index, gender, age, race, and history of hypertension.

LIMITATIONS

Data were pooled from studies which differed somewhat in study design and patient demographics. None of the studies were originally designed to examine treatment effects on BP. Study entry criteria limit generalization of these results to medically stable patients with a primary diagnosis of MDD.

CONCLUSIONS

Short-term desvenlafaxine treatment was associated with small but statistically significant increases in SSBP and SDBP.

Two Chronic Stress Models Based on Movement Restriction in Rats Respond Selectively to Antidepressant Drugs: Aldolase C As a Potential Biomarker

BACKGROUND

Clinically depressed individuals respond to different types of antidepressants, suggesting that different neurobiological mechanisms may be responsible for their depression. However, animal models to characterize this are not yet available.

METHODS

We induced depressive-like behaviors in rats using 2 different chronic stress models: restraint in small cages or immobilization in adaptable plastic cones. Both models increased anxiety responses evaluated by novelty-suppressed feeding and the elevated plus-maze; increased learned helplessness evaluated by the tail suspension and forced swimming tests; and increased anhedonia evaluated by the sucrose preference test.

RESULTS

We assessed the ability of 2 different types of antidepressants to ameliorate depressive-like behaviors. We administered the serotonin reuptake inhibitor fluoxetine or the noradrenaline reuptake inhibitor reboxetine once daily for 28 days to rats that received either chronic restraint or immobilization stress, or no stress. Behavioral analysis revealed that fluoxetine ameliorated depressive-like behaviors when induced by chronic restraint stress, whereas reboxetine ameliorated these behaviors when induced by chronic immobilization stress. To further test biological differences between both models, we evaluated the levels of Aldolase C, an enzyme expressed by forebrain astrocytes that is regulated by antidepressant treatment, in the cerebrospinal fluid: chronic restraint stress, but not immobilization stress, increased the levels of Aldolase C. Moreover, the presence of astrocyte-derived Aldolase C-GFP in the cerebrospinal fluid indicates its central origin.

CONCLUSIONS

Two stress paradigms induced depressive-like behaviors that were sensitive to different antidepressant treatments. Biomarkers such as Aldolase C could help determine optimal antidepressant treatments for clinically depressed patients.

Psychopharmacology

Primary care providers (PCPs) are frequently responsible for the pharmacologic management of mood disorders, and the PCP is often an important member of the clinical team in the management of bipolar disorder and schizophrenia. Not only is a good understanding of psychopharmacology important for the effective treatment of psychiatric disease, it is also necessary for patient safety. Clinicians should understand the side effects and the medication interactions associated with psychotropic medications. This article reviews mechanisms of action, indications, dosing, side effects, medication interactions, and general management considerations for common medications used to treat psychiatric conditions encountered in the primary care setting.

Serotonin and sudden death: differential effects of serotonergic drugs on seizure-induced respiratory arrest in DBA/1 mice

In the DBA/1 mouse model of sudden unexpected death in epilepsy (SUDEP), administration of a selective serotonin (5-HT) reuptake inhibitor (SSRI), fluvoxamine, completely suppressed seizure-induced respiratory arrest (S-IRA) at 30 min after administration (i.p.) in a dose-related manner without blocking audiogenic seizures (AGSz), but another SSRI, paroxetine, reduced S-IRA but with a delayed (24 h) onset and significant toxicity. A serotonin-norepinephrine reuptake inhibitor, venlafaxine, reduced S-IRA incidence, but higher doses were ineffective. A selective 5-HT7 agonist, AS-19, was totally ineffective in reducing S-IRA. In developing DBA/1 mice that had not previously experienced AGSz, administration of a nonselective 5-HT antagonist, cyproheptadine, induced a significantly greater incidence of S-IRA than that of saline. This study confirms that certain drugs that enhance the activation of 5-HT receptors are able to prevent S-IRA, but not all serotonergic drugs are equally effective, which may be relevant to the potential use of these drugs for SUDEP prevention. Serotonergic antagonists may be problematic in patients with epilepsy.

Synergistic regulation of glutamatergic transmission by serotonin and norepinephrine reuptake inhibitors in prefrontal cortical neurons

The monoamine system in the prefrontal cortex has been implicated in various mental disorders and has been the major target of anxiolytics and antidepressants. Clinical studies show that serotonin and norepinephrine reuptake inhibitors (SNRIs) produce better therapeutic effects than single selective reuptake inhibitors, but the underlying mechanisms are largely unknown. Here, we found that low dose SNRIs, by acting on 5-HT(1A) and α2-adrenergic receptors, synergistically reduced AMPA receptor (AMPAR)-mediated excitatory postsynaptic currents and AMPAR surface expression in prefrontal cortex pyramidal neurons via a mechanism involving Rab5/dynamin-mediated endocytosis of AMPARs. The synergistic effect of SNRIs on AMPARs was blocked by inhibition of activator of G protein signaling 3, a G protein modulator that prevents reassociation of G(i) protein α subunit and prolongs the βγ-mediated signaling pathway. Moreover, the depression of AMPAR-mediated excitatory postsynaptic currents by SNRIs required p38 kinase activity, which was increased by 5-HT(1A) and α2-adrenergic receptor co-activation in an activator of G protein signaling 3-dependent manner. These results have revealed a potential mechanism for the synergy between the serotonin and norepinephrine systems in the regulation of glutamatergic transmission in cortical neurons.